CA1242775A - Optical position location apparatus - Google Patents

Abstract

S P E C I F I C A T I O N

OPTICAL POSITION LOCATION APPARATUS

Abstract of the Invention An optical position location apparatus for locating the position of an object in one or more dimensions, which relies upon one or more sources of radiant energy and distribu-tor devices to disburse such radiant energy over a location region or window. Integrated collector assemblies positioned opposite to the distributors receive and collect the transmis-sion of the distributed radiant energy and through reflection or refraction, transfer radiant energy to a minimum of detec-tion locations to monitor the absence or alteration thereof.
A rotating optical scanner and a detector are utilized with a continuous stationary light source to successively monitor specific location-coordinate-related portions of transmitted radiant energy and through electronic circuitry, a signal is developed to disclose, with accuracy, the location of objects within the location region "window", as well as other parameters including object size. In other embodiments, an apparatus with elements cooperating along two dimensions is capable of yielding three-dimensional object parameter information.

Description

Background of the Invention The present invention relates, in general, to elec-tronic sensing equipment and in particular to an optical pOfiition location apparatus for locating the position of an object along one or more coordinate axes and for determining other measurable parameters of the object.
There have been several devices in the past which have optically, or through a combination of mechanical and optical devices, had, as a purpose, the location of an object within a one- or two-dimensional frame of reference. Unfortunately, more recent attempts into the field of electro-optical "range finders" and/or "locators" have often been associated with problems which severly limit their effectiveness and use on a large scale. Two such devices are disclosed in U.S. patent application No, 3,184,847 of L. Rosen on a Digital Coordinate Resolver, and in the article Let Your Fingers do the Talking in Volume III, No. 8, 8YTE Magazine, dated August, 1978, on a non-contact touch scanner.
Arnong the undesirable aspects of all the prior art, are the substantial costs involved with the unusually large number of components required to construct the devices into even a marginally operative apparatus. Reliance upon literally doæens of light emitting sources wlth equivalent numbers of "matched" photocell diodes has substantially limite~ the effec-tiveness and resolution of prior art optical scanners while, at the same time, requiring substantial expense in terms of costly electronic components which have made uses and applications of the devices impractical.
Other prior attempts have required the attachment of gratings~ photocells, or other special paraphernalia to the object being located.

-2-. Similarly, the design of most prior art. devices often proves to be difficult in terms of compatability w$th display devices which are capable of otherwlse showing the results of the scann~ng operation. ~oreover, where such display devices were utilized, the devices themselves required reinterpretation due to an inflexible~ "non-l~near~ output of such devices.
Some prior art devices have required retroreflectors and, therefore, exper$ence great difficulty locating reflective objects~
Prior art devices all too often relied upon less advanced optical techniques such as the Rosen device above, whereln parabollc mirrors, through their very nature require ~ubstantial size parameters. Additionally~ great difficulty has been èxperienced in extending the capabllities of prior . art devices beyond one or two dimensions, and few, if any, apparata have been capable of effectlvely re olving the loca-~ion and other parameters of an object within a three-dimensional "corridorn, or along three or more coordinate ax~s arranged in two d~mensions. Moreover, prior ar~ dev~ces have suffered from limited spacial resolution and low scan rates, and, therefore, limited temporal resolution.
Th~s the present invention seeks to provide a substantially inexpensive optical position locator requirin~ a minimum of components which is subfitantially com-pact and lightwe~ght and which, accordingly, is manufacturablein a facilitated manner in substantlal volumes.
Further the present in~ention seeks to provide such a position loca~or with substant$al spacial and temporal resolution capabllities whlch is designed to quiickly and accurately disclose parameters of an object located within its location region or "windown.

. 3--Still further the present invention seeks to dis-close positlon and other para~eters of ordinary untreated objects ~uch as ~ingers, p~ns, or p~ncils.
The present invention seeks further to provide such an optical po~ition location apparatus ~hlch 15 com-patible with a variety of display output~ and which i5 capable of discloslng locati~n in~ormation for ei~her ~nalysi~ by ~ user, or for fu~ther input into other systems, ~n a desirable fash~on to avoid complex conv~rs~ons, such a~ in linear fashion 80 as to avoid requirlng trignometric conversion program3, The present appa~atus also has, among it8 ~eatures, the provision of an efficient, low-cost, accurate location apparatus which, by it~ very design, i8 appl1cable for use in a myriad of ~pplication~ ranglng from computer inEormation input (as a viable alternatlve to light pens and keyboards), to toys, automatlc industrlal machinery controls and any other u~es, such as menu plcking where expedited automatic determinatlon of object parameters such a~ location, slze and even speed, are reguired.
The present invention further is adaptable to analysis of a three-dimensional "corridor" and the location and other parameters o an object wlthin that three-dlmensional space through ~e~eral dif~erent const~uctions, includ-lng the stacklng o~ ~everai t~o-dimensional units and/or rellance upon radiant energy in~ensi~y l~vel analy~is in a single two-dimens10nal unit whlch i3 capable o disclosing a third dimenslonof an object within lt~ location reglon window. ~et, another embodiment u~ilizes three-dimen~onal distributors, collectors and ~elective viewlnq scannersD :
Further the present invention seeks to provide a device which requires a minimum of light or radiant energy emission sources and photodetection devices through the utilization of a single radiant energy source with a novel rotating selective ~ t7~

viewing scanner and associated detector which, in combination with novel electronic circuitry and a minimum of electronic componentsl accurately and quickly disclose the parameter information described above.
Yet further, the invention seeks to convert complex motions, such as those of human fingers in motion, into time varying signals to enable a person to so convey vast amounts of complex information to machines or other persons.
These and other aspects of the invention will become apparent in light of the present specification.
Summary of the Invention The present invention comprises an improved optical position location apparatus for locating the position of an object within a location region or "window" along ons or more coordinate axes arranged in one or more dimensions and for determining yet other measurable parameters of such a located object such as its size, its opacity, its composition, or its velocity vector.
The invention in one broad aspect pertains to an optical position locating apparatus for locating the position of one or more objects along one or more coordinate axes o~ a defined area, as well as for determining other measurable parameters of the one or more objects such as the sizes thereof relative to the one or more coordinate axes. The apparatus comprises radiant energy emission means, radiant energy detection means, and distributor means for dîstributing the radiant energy emitted by the radiant energy emission means over a location region from a position along a first portion of the region. One or more integrated collector means is positioned along a second portion of the location region, and cooperates with the distributor msans to receive the radiant energy distributed by the distributor means and to transmit the radiant energy to the radiant ,J ~' energy detection means. Means are provided for selectively viewing portions of the distributed and received radiant energy to disclose properties of the radiant energy which have been altered as a result of the object being located within the location region so as to, in turn, determine the location of the object within the location region, as well as the other parameters of the object.
More particularly, the apparatus comprises radiant energy emission means, and means cooperating with the radiant energy emitter to distribute the emitted radiant energy over the location region from a position alongside one portion of this region. One or more integrated collector means correspond to the distributor means, respectively, and are positioned along a second portion of the location region, substantially opposite to the first portion, to cooperate with respective ones of said distributor means. The integrated collector means receive and transfer the radiant energy which successfully traverses the location region, as well as indications of alterations thereto, to detection means, preferably located at a singl~
location to which the transEerred radiant energy converges.
The apparatus further includes means for selectively viewing location-coordinate-related portions of the radiant energy distributed by the distributor means to detect and disclose properties of radiant energy which have been altered as a result of the object being located at that location coordinate within the location region to, in turn, determine the location of the object within the location region, as well as other parameters of the object.
Distributor means, collector means, and selective viewing means cooperatively ensure that at a given moment, substantially all of the radiation which reaches the detector, in the ; -6-~ t~5 absence of objects in the location region, traverses the location region in a range about a single location coordinate, such range being at least as small as the smallest object to be located. Moreover, a plurality of distributor means jointly ensure that each portion of the location region large enough to contain the smallest object to be located, will be traversed by at least as many intersecting radiant emission beams as there are coordinate axes.
Accordingly, the present invention distributes radiant energy from a source into a region in an orderly fashion, collects and transfers that energy which traverses that region to a detec-tor, and selectively views location--coordinate-related portions of that radiant energy--all for the purpose of deducing the loca-tion and/o~ other parameters of one or more objects within that region, from the alterations of the radiant energy traversing that region.
In a preferred embodiment of the invention, the appara-tus includes an enclosing housing member in which the radiant emi6sion means or source of radiant energy, the distributor means, the integrated collector means, the selective viewing means, and the detection means are operably and restrainably positioned and sealed. In this embodiment, the location region is described as a substantially apertured area enclosed by the housing member ~o describe a substantially t :oidal housing element.
The apparatus is capable of functioning as a position location apparatus along one or more coordinate axes in from one to three dimensions. That embodiment of the device capable of locat-ing the position of an ob~ect in one dimension includes one each of radiant energy emission mean~, distributor means, integrated collec-tor means, selec~ive viewing means, and detection means.
In that embodiment capable of locating the position of an object along two coordinate axes in two dimensions, the ~29~

apparatus preferably includes two substantially separate dis~
tributor and collector means respectively aligned with one another. In this particular embodiment where two of each said collector means and distributor means are utilized, measuring the intensity of the received radiant energy being transmitted to the detection means, can further be utilized to disclose information relevant to, for example, the height of an object so as to describe information in three dimensions while utilizing distribution collection, and selective viewing means along only two dimensions.
Alternatively, one embodiment of the apparatus is further contemplated to disclose and scan objects in a three-dimensional location region through the utilization of "stacked"
two-dimensional locating devices so as to impart location capabil-ity along a third coordinate axis throughout a three-dimensional spacial "corridor".
In a preferred embodiment of the invention, the ~adiant energy emitted b~ said radiant energy emission means comprises unpolarized electromagnetic light and emission means comprises an incandescent lamp.
In one preferred embodiment, the radiant energy emis-sion means is associated with rotating projecting selective viewing means to transmit a successively moving light beam which is conti~ ously moved along the distributor means then traverses the location region, moving along the location coordinateJ and, in turn, move~ along the respective collector means as a function of time. In this particular embodiment, also, the detection means comprises a single stationary photo-sensitive element which cooperates directly with the collector from which radiant energy is directed so as to converge at the photo-sensitive cell. The detection cell cooperates with signal processing means, which as a function of time, discloses altered or blocked light transmissions to, in turn, describe the location of an object within the location range. The radiant emission means can advantageously comprise a laser.
In another embodiment of the invention, the radiant 5 energy source comprises a plurality of individual light sources placed in spaced relationship along the first portion of the location region so as to further, æimultaneously, comprise the distributor means. In this particular embodiment, each of the pl'urality of light sources comprises a light emitting diode, behind a series of baffles and/or other optical elements which create a substantially parallel beam across the location region, to collector means respectively aligned therewith. Further, in this embodiment, the detection means comprises one or two photo-sensitive ~elements which cooperate with the collector means aligned opposite to the bank of light emitting diodes. The means by which said detection means selectively views portions of the distributed and received radiant energy emissions, namely, the radiant energy ~rom each of the light emitting diodes ls accom-plished by pul~ating each of the llght emitting diodes in sequence, with the detection means element cooperating with signal process-ing apparata to disclose altered or blocked light transmission properties to~ in ~urn, describe the location or other parameters of an object within the location range.
' ' In a preferred embodiment of the invention, ':he radi-ant energy emi sion means compr~ses a substantially stationary continuous light source and inc'ludes a plurality of shields which intercept and absorb radiation directed to locations other than those along the respective distributor means. In this particular embodiment, the ~etection means is associated,with selective viewing means which comprises a rotating scanner to selectively analyze portions of the continuous radiant energy simultaneously distributed across the location region. The _g_ -scanner and detector receive radiant energy in either its direct or altered form and, in response thereto, produce an electrical output proportional ~o the amount of radiant energy being measured, the radiant energy being altered to a differentiable measurable degree by any objec~ blocking the radiant energy being distrib-uted across the location region.
In this preferred embodiment,-the associated scanner and detector include shield means to absorb radiant energy not transmitted from the respective integrated collector means to the detector and which serve as points of reference (synchronization indicia) for the signal. The scanner and detector itself com-prises a motor operably connected to rotate an optical element.
A slotted mask is operably attached to the optical element and rotates simultaneously with it--this slotted mask providing a dimensionèd slot to describe the "portion" of transferred radi-ant energy detected at one instant during the rotation of the scanner-detector, said portion having traYersed the location region in a range about a single location coordinate. The scanner-detector further comprises a stationary detector element operably positioned in alignment with the optical element and slotted mask.
The radiant energy is thus transferred from the res-pective integrated collector means so as to enter the optical element for refraction through the ~lotted mask and, in turn, to the stationary surface of the detection elementf a diode photocell. The rotating optical element and mask permit the scanner assembly to scan, position by position, across one coordinate axis of location range emissions described by a res-pective integrated collector and to, in turn, scan across the remaining coordinate axes of location range emissions described by remaining collector means in repeatable succession.

The optical element can comprise an optical sphere containing therein a dia~onal-cut refraction plane to appro-priately refract the radiant energy into and through the slotted mask and, in turn, onto the stationary detector element which, in the preferred embodiment comprises a si}icon photocell.
More genera}ly, the optical element can be a bi-radial ellipsoid, with horizontal radius and slot width cooperatively establishing width of view, while vertical radius and slot height cooperatively establish he~ght of view.
While blockage means are used in conjunction with the radiant energy emission means of the embodiment described immediately above, to intercept and absorb radiation directed to locations other than those along the distributor, equiva-lent b}oc~age means or shields are utilized with the scanner-detector, as previously mentioned, for the three-fold purpose of precluding inadvertant stray radiation from being received - by the scanner, providing a position frame of reference whereby different input from different collectors can be segregated and analyzed to determine the dimensional parameters of an object wi~hin the location range and providing a black-level reference.
In this preferred embodiment also, the scanner-detector apparatus may be operably coupled, through the signal process-ing means to visual display means for visual interpretation of radi;~ energy being scanned and detected thereby.
Further, the motor in this scanner-detector embodiment is coupled via electrical circuitry to ~he radlant energy emis-sion means together with the detector element and amplifier means. In this circuitry, the motor further includes a capacitor connected in parallel ~hereto, to reduce commutator noise from the motor and is further connected to resistors ~o reduce volta~e and, in turn, produce a desirable rotational speed in the motor, the temporal resolution being in inverse relationship to the ~L2~

rotational speed. The amplifier is operably connected to the detector element in said scanner-detector.
The amplifier, in this circuitry, responds to the inten-sity of current released through the detector element, which, preferably, comprlses a photo~sensitive diode operating in reverse biased mode. The amplifier itself further includes first voltage gain means with noise suppressant means to transduce the variable current of the photo-sensitive diode into a resulting variable voltage signal. A second voltage gain means is coupled capacitively to the first voltage gain means and is, in turn, connected to a d.c. restorer and to a Schmitt trigger to quantize the resulting signal to one digital bit, thus removing noise.
For that embodiment of the invention in which intensity of signal is measure~d, the Schmitt trigger would be replaced by a buffer amplifier~
Also, a means for visual interpretation of the scanned and detec~ed radiant energy transmitted by the signal processing apparata, comprises a ca~hode ray visual display apparatus such as an oscilloscope or equivalent.
æo In one embodiment of the apparatus, the invention fur-ther includes radiant energy filter means which are interposed between the distributor means and the collector means for the purpose of substantially removing all radiant energy not having the wavelengths passed by the filter so as to reduce both interr-l and external stray radiation~ In one such embodimen~, the filter means comprlses an infrared passage filter interposed between the location region and the position location apparatus.
Preferably, the distributor means is capable of dis-~ributing radiant energy at positions before and beyond its re~pective portion of the location range to descrlbe an initial and final radiant energy route which cannot be altered or broken by objects no ~atter where ~hey may be positioned within the -" ~ 2~

location ~ange. This, in turn, describes reference points to fac~litate analysis of detected radiant energy across that pottion of the range which is breakable by a located object and to further avoid confusing an object located at the extremes of the location range as being a portion of the shields associ-ated with the scanner-detector.
In the preferred embodiment of the invention, further, the distributor means comprises a stepped echelon mirror assem-bly ~or receiving radiation from the radiant energy emission means to, in turn, distribute it across th~ location region.
Similarly, the preferred embodiment of integrated collector means utilizes an equivalent stepped echelon mirror assembly for receiv-ing the radiant energy distributed over the location region and for subsequently transferring it to a substantially single point location at which said detection means is located.
The construction of the distributor or collec~or, whichever is most adjacent to a rotating scanner, establishes the functional relationship between the location coordinate and the scanner rotation angle. In particular, the distributor or collector (whichever controls said functional relationship~
is designe~ for a substantially linear relationship between position coordinate and scanner rotation angle. The stepped echelon assembly lends itself favorably ~o the establishment of a variety of arbitrary functional relationships because it allows independent local specification of both mirror position and mirror slope (reflecting angle). For example, a preferred embodiment utilizes a 29 facet stepped echelon assembly as a collector which provides a linear relationship between location coordina~es and rotational scan angles, while maintaining light intensity substantially constant. In the 29 facet embodiment facet peaks are spaced .2 inches apart and the facets range, in curvilinear fashion, from a depth of 1.617 inches to .171 inches.

The construction of both distributor and collectorestablish the functional relationship between relative inten-sity-of transferred radiation, in the absence of objects, and location coordinate. In particular, it is possible to design the distributor and collector taken as a system to establish a desired relationship between relative intensity and location coordinate. The stepped echelon assembly again lends itself to the establishment of such a relationship because the vari-ous reflecting facets can have differing effective reflection areas. The effective reflection araa i5 that area which lies in the desired plane and is not shadowed or obstructed by other portions of the echelon assembly and therefore is effec-tive in transferring radiation to or from ~he location region.
The width~of the largest shadow must be smaller than the width of the smallest object to be located. The stepped mirror assembly can be skewed to substantially eliminate shadows, the facets becoming parallelograms.
For largPr location regions, the individual faces of the stepped echelon mirror assemblies may be focusing surfaces shaped so as to maximize radiation transfer.
In alterna~ive embodiments, both ~he dis~ributor and collector assemblies are non-stepped reflective surfaces such as where both the collector and distributor assemblies are parabolic secti ns, though size and cost problems may be associated therewithO
In other alternative embodiments, both the dis~ributor and/or the collector assemblies are refractive or a combination of reflective-refractive assemblies. Lenses or prisms would be examples of refractive assemblies, while a combination reflective-refeactive assembly would be exemplified by a stepped echelonstructure of transparent optic material which has a reflective coating on its rear surface wherein the light is both refracted and reflected.
In the 18 faceted embodiment of stepped echelon mirror, less space requirements exist due to a thinner oonstruction which is traded off against less constant light intensity properties as well the need for ~rigonometric conversion programming due to its non-linear coordinate versus scan angle relationships. The ..
peaks of this 18 facet embodiment are spaced .375 inches apart and range, in curvilinear fashion, from a depth of 1~392 inches to .815 inchesO

- ~2~

~rief Description of the Drawin~s Fig. 1 of the drawings is a top plan v~ew of a preferred embodiment of the scanner apparatus in which a scanner-detector is utilized together with stepped echelon collectors and distribu-tors for locating an object in a two-dimensional location range;

Fig. 2 is a top perspective view of the scanner-detector device of the embodiment of Fig. l;

Fig. 3 is a top plan view of the optical element of the scanner-detector;

Fig. 4 is a side elevational view of the optical O element of Fig. 3;

Fig. 5 is a circuit diagram of the components utilized in the scanner embodiment of Fig. l;

Fig. 6 is a circuit diagram of the amplif ier circuit of Fig. S;

Fig. 7 is a schematic view of output display in which the location region is empty or unobstructed;

Fig. 8 is a schematic view of output display in whlch an object is located within the location range;

Fig. 9 is a schematic view of output display showing O the output signal before the d.c. restorer portion of circuitry is incorporated;

Fig. 10 is a schematic view of output display after the d.c. restorer portion of the circuit is utilized;

Fig. 11 is a top plan view of one embodiment of stepped echelon mirror assembly, appearing with Fig. 13;

~2~

Fig. 12 is a second embodiment of stepped echelon mirror assembly;

Fig. 13 is a top plan view of an alternative embodi-ment of optlcal scanner apparatus in which integrated collector means are utilized with a plurality of light emitting sources which serve simultaneously as di~tributor mean~i Fig. 14 is a top plan view of the scanner apparatus including continuous parabolic collectors and distributors;
Fig. 15 is a top plan view of a portion of the scanner apparatus depicting utilization of refractive elements;
Fig. 16 is a side elevational view showing the effect of an opaque object interceding into the space defined by mirror elements oriented at three differing skew angles;
Fig. 17 is a top plan view of the scanner apparatus utilizing liquid crystal stripe mask scanners in conjunction with the optical detector;
Fig. lB is a detailed side elevational view of the liquid crystal stripe mask and associated electronics;
Fig. 19 depicts use of an oscilloscope to display the output waveform of the optical position location apparatus;
Fig. 20 depicts an opa~ue object inserted to various depths within the detection region of the device;
Fig. 21 is a schematic view of an output display for various depths of penetration as shown in Fig. 20.

~L2~

Detailed Description of the Drawings . While this.invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail, several specific embodiments, with the understanding that the present disclosure is to be considered as an exemplification of the principles of the inven-tion and is not intended to limit ~he invention to.the embodi ments illustrated.
Optical position location apparatus 20 is shown in Fig.
1 as including radiant energy emission source 28, here comprising a continuously radiating stationary incandescent light bulb, with shields 27 and 29 and scanner-detector 48 with shields 18 and 19, all in housing 20a. Shields 27 and 29 preclude the emission of light beams to locations other than those along distributor assemblies 32 and 40.
In this part~cular preferred embodiment, distributor assembly 32 comprises a series of mirrored surfaces forming a stepped echelon such as mirrored surfaces 33, 34 and 35, capable of reflecting the divergin~ light beams from light source 28 into - a substantially parallel light beam pattern across location region 21~ Both collectors 41 and 42 are specifically designed to enable detector-scanner 48 to rotate a substantially equivalent radial scan angle ~o monitor a respective equivalent linear distance across location region 21. Accordingly, when detector-scanner 48 is rotating, an equivalent angle of rotation allows the scanner-25- detector to monitor an equivalent portion of the location region "window" 21 regardless of the path a particular light beam follows in being refiected to cross the window. This particular construc-tion linearizes the output display location coordinate as 'a func-tion of radial scan angle and, ~herefore, as a function of time in the devices shown ln Figs. 7 through 10.

It should be noted that mirrored surfaces on dis-tributors 3~ and 40, are provided at ~ocations 50 and 51 at assembly ends B and A, respectively;.and 45 and 44 on assembly 40~ in order to transmit and distribute radiant energy beams across portions of the "w1ndow~ preceding and subsequent to the actual locat~on region in which an object can move. Transmission of light from bulb 28 to location 44 at end A of.distributor 40 transmits a bea~ across the actual edge 24 of red and infrared passage filter 23, which is substantially collected and received by mirrored su~face 47 for reflection to scanner-detector 48~
Since no object can occupy a position outside of window 2} to interfere with the beam thusly transmitted, the signal created by an object within the location region, as di~played in Fig, 8, cannot mer~e with the displayed repre8entation of the shields.
L5 r.~ , ob~c~.s ~v~n at th~ periph~ry of .locati~ x~ion 21 ~
readily distinguished from the effect of the shields, as shown by space 121 in Fig. 8.
Apparatus 2~ dlsclo~es the specific embodiment of scanner apparatus for locating and measuring an object's para-meters in two dimensions whe~ein tke two distributors, 32 and 40, are arranged opposlte t~ collectors 41 and 42, respectively.
Since liqht source 28 is a ~tationary c~ntlnuo~s source o~ electro-magnetlc radiant energy, a continuous beam pattern is generated, as exempl~fied by beams 30 and 31 along the X-coordinate and beams 14 and lS bein~ distributed from distr~butor 32 to collec~or 41 in the Y-coordinate. Accordingly, the existence of an object such as object 52 ~shown in phan~om) would block or o~herwase alter radiant energy beam 1~ as it ~s reflec~ed from mirrored surface 33 ~o mirrored surface 36. Aceordingly, when scanner-detector 48 rotates ~o review that portion of radiant energy which would otherw~se be reflected ~rom mirror surface 36, the output display, as shown in FigO 8, would show object 52 a dis-tance of Yl rela~lve to the radial time distance from shield 18.

While the arrangement of distributors and collectors in the embodiment of Fig. 1 are substantLally orthogonal, the apparatus could equivalently utili~e non-orthogonal or angled scanning beam patterns. Red and infrared passage filter 23 is utilized to pass only the red and infrared wavelengths across the posi-tion location range and also to exclude all non-red or non-infrared stray radiation from entering from outside the apparatus so that such stray light cannot upset the operation of the apparatus.and for sealing and enclosing the substantially toroidal housing. Other radiant energy filter means may equivalently be utilized including an all-pass (clear) window. Each of the respective stepped echelon mlrrors, whether used as a distributor or collector, has at its large end A
and small end B, respectively, mirrored surfaces which permit reflection and transfer of radiant energy outside the "blockable" portions of the location region window 21.

Non-stepped mirror assemblies may be utilized, such as parabolic mirrors 282 - 285 shown in Fig. 14. However, such configurations may require substantially deep curvilinear mirror forms which greatly enlarge the size and costs associated with the device -- problems which are overcome by the specially designed stepped echelon mirrors. Alternatively, refracting means such as lenses or Fresnel type lenses or refracting-reflecting means such as a mirrored prism, may be used in palce of distributors 32 and 40 and/or collectors 41 and 42, to transfer diverging light from light source 28 through refraction and/or refraction-reflection into substantially parallel beams across window 21 or, alternatively, to detection means. Fig. 15 illustrates the use of focusing lenses 290 in conJunction with distributor 40, wherein reflected beam 291 is further columnated into focused beam 292 by lenses 290.

Optical scanner 48 is shown in Fig. 2 as comprisiny motor 53 with axle 54 connected to optical element 56 - 57 through attachment member 55. Attached or rotation to optical member 56 - 57 is view restriction means or mask-baffle 61 with apertured slot 62 which permits transmission of analy~ed light "portions" to impinge upon detector 60 with electrical leads 63.

Scanner 48 as shown in Figs. 1 and 2, ro-ta-tes to receive radiant energy transmissions from collectors such as collector 41, though only a portion of the transmitted beams are permitted to reach detector 60, preferably a silicon photocell diode, as limited by slotted aperture 62. Preferably the depth of the region viewed by detector 60 is slightly greater than the thickness of the reflective elements of co]lectors 41, 42. In this manner, slight axial misallgnments of the scanner 48 are tolerated without less of desirable signal, yet extraneous radiation is substantially blocked.
In rotating at a constant speed, reflections from collector 41 are first reviewed by the detector as it rotates clockwise, then, absence of light is displayed as a result of the scanner viewing shield 19. This is followed by the scanner reviewing reflections f.rom collec-tor bank 42 followed by -the absence of light due to shield 18, and so on.
Preferably, shields 18 and 19 are black and oqaqu~ to mor~
eEfecti.vely absorb unwanted radiation. Silicon photocell 60 i.s mai.ntained in a stationary position above rotating mask 61.
,:. Optical Qlement 56-57 comprlse~ an optically ~ransparent sphere, here acrylic, cut into two hemispheres. The lower hemi-sphere 56 is utilized solely as a balance to facilitate even rotation of the optical device by motor 53 and shaft S4. Hemi-sphere 57 has back planar surface 57a wh~ch is, preferably, optically pollshed. The outwardly exposed surface of hemisphere 57, which is shown in Fig. 2 receiving radiant energy beams 53 ~hrough 60, ac~s as a converging lens surface. Total in~ernal reflection takes place at ~urface 57b due to the nominal index of refraction of the materia~ u-;ed (acrylic having an index of 1.5) a~ opposed to the 1.0 index o the air space ma~ntained by ~pacer p~ns 64 ~nd 65, locat~d at ~he back planar ~u~face 57a.

The optical device is shown in Fig. 3 before top sec-tion 68 as shown in Fig. 4, has been removed, and through Figs. 3 ~L2f~2~o~
and 4, the construction for the optical device which includes spacer pins 64 and 65 and hemisphere portions 56 and 57 are shown. Spherical sections 66 and 67 are opaqued.
Alternatively, they may be cut away and the surfaces so exposed may then be opaqued.

-21a-In the preferred embodiment of the scanner-detector, Acrylite 210-0 or Plexiglas 2423 are used in forming the red and infrared pass filter 23, sealing off the interior of the "donut-shaped" apparatus assembly. A three-quarter inch diameter acrylic sphere w~ll serve for the optical element 56-57, although glass can equivalently be used, The width of slot 62 is .014 inches.
With the front "converging lens~ width o~ hemisphere 57 approxi-mating 0.3 inches, an approximately 0.3 inch wide beam of light from the filament of lamp 28 (G.E. No. 194) traverses the location region and passes through slot 62 onto photo detector 6G which must be spectrally compatible with radiant source 28. In the pre-ferred embodiment, photo detector 60 comprises silicon photodiode VACTEC VTS-4085H.
In circuit arrangement 70 of Fig. 5, input power applied to +V and OY is at 12 volts d.c. at nominal 0.35 amps, regulated to 5 percent. Lamp 71 is directly connected across ~he 12 volts.
Motor 75 is paralleled by capacitor 74 for noise suppression.
Preferably, this capacitor should be a wide band RF bypass type such as a 0.1 to 0.01 microfarad metallized polyester capacitor.
Resistors ~2 and 73 reduce the 12 volts d.c. to a nominal posi-tive 5.7 volts d.c. to produce the desired rotatlonal speed in motor 75. This ~peed is high enough for the desired scanning rate, yet low enough for good motor life and ease in data pro-cessing. A wide range of rotational speeds could be produced by using an appropria~e d.c. or. a.c. motor driven by an appro-priate d.c. or a.c. voltage source. In some applications, a synchronous motor is preferred, and for others, a stepping motor is preferred~ The former assures a constant scanning ra~e; the latter~ quantizes the location range without the need for software calculations. An appropria~e d.c. motor for use in the preferred embodiment of Fig. l would be a MABUCH~
RF-510T-12620 with a nominal rotation speed of ~400 r.p~m.

-~2-Photodiode sensor 76 i~ operatively. connected to amplifier assembly 77.
Amplifier 77 is shown ln Fig. 6 as including five separate sections of a CMOS 74C94 hex-invertor. Pin 7 of thè
74C04 connect6 to the OV rail and pin 14 of the 74C04 connects to the positive rail at the cathode of dlode 81, thus apply-lng 1~ volts less one diode drop to the 74C04 and thereby establishing Vcc at approximately 11.3 volts. Alternatively, oper~tional amps 86, 91, 92, 99 and 100, w~th appropriate circuit modifications each compr~se a Texas Instruments TL081, a section of Texas Instruments TL084 or a National Semiconductor LM308 amplifier. The first portion of amplifier 77 is a voltage gain stage where 2.2 megohm resistor 85 sets the input current to output voltage gain. A 10 picofarad capacitor 84 rolls off the high frequencies to reduce noise. Resistor 85 also maintains photodiode reverse bias voltage. The output of this stage is coupled by back-to~back, polarized 10 microfarad capacitors 87-88 or alternatively by a 10 microfarad non-polarized capacitor, to second ~tage input resistor 89. Second operational amplifier 91 is connected to one megohm feedback res~stor 90, and with 100 kilohm resistor 89, it yields a nominal voltage gain of 10. This output is coupled through capacitor 95 of 0.1 microfarad to 10 kilohm resistor 96, op amp 92 and diode 97, tlN914). Op amp 92 and d~ode ~7 act to clamp the signal so that it cannot go posi-tive of the bias point of the amplifier (nominal 1/2 Vcc). The 470 kilohm resistor 93 holds the output of the capacitor g5 against the clamp level. Elements,92, 93, 96, and 97 constitute a d.c. restorer. The d.c. restored s$gnal (where the most posl tive d.c. level is 1/2 Vcc) is coupled to a Schmitt trigger 98-101. Op amps 99 and 100 are coupled in the Schmitt trigger to 4.7 megohm feedback resis~or 101 and 220 kilohm ~nput resis-tor 98. 1.5 megohm resistor 94 biases the Schmitt trigger point ~ ~ ~1~1~3 referred to the input of res~stor 98 to slightly.negative of the d.c. base line set by the d.c. restorer. Resistor 101 sets th~ hysteresis along with the 220 kilohm resistor 98 which also affects the input sensitivity. The two 470 ohm resistor~, 102 and 103~ together with diodes 104 and 106 llN9l4) protect the output against static electric di charges or othec accidental stress. A 10 microf~rad electrolytic capacitor 105 serves as a power supply filter.
Diode 81 protects against damage due to accidental polarity reversal, and can further serve as a rectifier for embodiments uslng a.o. applied power.
In the circuit arrangement of Fig. 6, photodiode 76 acts as a cureent source which is light controlled.
In operation, when the scanner-detector 4~ of Fig. 1 is facing or focusing upon shlelds 18 and 19, the d.c. restorer clamps the s~gnal to 1/2 Vcc. This is the plus-most input to the Schmitt trigger portion of the clrcuit. The bia~ resistor 94 of l.S megohms, causes the Schmitt trigger to have a net plus input under this condi~ion, and the output is, therefore, near the +12 volt rail tm~ximum output~ of Fig. 7. When the scanner looks across the unimpeded range a~ a view or re~iec~ion of lamp 28, the signal level at thephotodiode swlngs relatively negative.
The output proximate to capacitor~ 87 and 88 goes relatively posi-tive and the output at capacitor 95 goes relati~ely nega-tive.
The output after the d.c. restorer therefore swlngs negative of the nominal Vcc restorer level. The net input ~o the Schmitt trigger ~8 101 goes negative o the lower trigger level, and the final output goes to th~ zero vol~ rail (minimu~ voltage value-base posit~on) of output as ~hvwn in Fig. 7. Should.an object such as object 52 appear which absorbs or blocks radiation for par~ of the scan as shown in Fig. 1, where radiation be~m 14 would be blocked, then ~or that portion of ~he scan, the output ~2~

of the photodiode returns to its "dark" level ~no current~, the output out of the first gain stage goes relatively negative, the second ga~n stage output goes relatlvely positive and the signal restorer returns to the 1/2 Vcc base line as shown in Fig. 7 with the output going to its fi~st logic position (maximum output position) as shown by output 52a and 52b in Fig. 8.
Accordingly, Fig. 7 of the drawings displays the posi-tions of ~hields lR and 19 when no object is interferring with the distribution of radian~ energy across the location region.
5hield poetion 113 and 111 in Fig. 7 are merely continuations of th~ same substantially large shield 19 while signal represent-ation 112 displays the logic one display (maximum output position) of smaller shield 18 about scanner-detector 4~. The position along the X- or Y-coordinate axis when an object does register, by altering th~ light input to photocell 60 is shown by the vari-able X (115), and variable Y ~114), respectively.
Fig. 8 depicts a typical output waveform of the device when an object is located within the location region window 21, such as object 5~ shown in ~ig. 1. Logic one level outputs 119 through 121 cor~espond to the light blockage resulting from shields 18 and 19 as described above. Additional logic one level outputs 52a and 52b are shown located within the X and Y scan regions 116, 117, re-spectively. These outputs correspond to the light block~ge result-ing from an object located within the locatiQn region window 21.
Because of the relationship between the scanner rotational angle and the range position along the X and Y coordinate axes, it is possible to ~educe from the location and t~e width of such logic one level outputs 52a and 52b the location and size of the interfering object 52 within the location window 21. Specifically, .~0 the offset of the rising edge o output 52a from the zero or be-ginning point of the X scan 115, which offset distance is designatec as Xl in Fig. 8, corresponds to the location of the n~arest edge of interfering object 52 to the zero axis point along the X axis of the location region window 21. Hence, by knowing the functional re-lationship between the scan angle in degrees represented by this offset Xl and the corresponding linear displacement along the X axic of the location region window 21, the actual location of object 52 may be determined. In a ~imilar fashion, the location of object 52 0 along the Y axis may be deduced from the offset Yl of the rising edge of signal 52b fro~ the zero or null position of ~ scan 114.
Additional information may be obtained $ro~ the outp~t wave-form as sho~m in Fig. ~ relating to the size of interfering object 52 relative to the X and Y axes. Specifically the width OL signal 52a, shown as delta X in Fig. B, corresponds to the width o object 52 relative to the X axis. Similarly, the width of signal 52b, delta Y, corresponds to the size of object 52 relative to the Y
axis. Hence, by knowing the relationship between the angular dis-placement represented by delta X and delta Y and the corresponding 0 linear displacement along the X and Y axes, the size of the object 52 may be determined.
Fig. 8 urther depic~s off~et region 122 located between the falliny edge of output 119 and the depicted beqinninq point of X scan 115. Similarly, offset region 123 is shown between the end point of X scan 115 and the rising edge of signal 120, with offset region 124 located between the falling edge of signal 120 and the beginning point of Y scan 114~ Finally, offset region 154 is shown between the er~d point of Y scan 114 and the rising edge of signal 1~1 .
These offset regions 122 through 125 correspond to unilnter-ruptable light signals which are trans~itted external to the loca-tion region window 21~ such as along its immediate external peri--25a-pnery, from the light source 28 to the scanner-detector 48~ The existence of these light signals results in a f ixed duration logic zero output just prior to and just following the X and Y scan.
These signals may thus be utilized to provide calibration of the 5 detection and/or interpretation circuitry, such as to define the existence and exact size of the X and Y scans 115, 116. It should be noted that, although such non-interruptable signals are provided for the beginning and ending points of both the X and Y scans in the embodiment whose output is ~how~ by Fig. 8, other e~bodiments ao may uti~ize fewer than all of these possible calibration signals as desired.
~ ig. 9 of the drawings depicts the relative voltage levels existent in a typical output signal prior to operation o the d.c.
restorer portion of the circuit. Speciflcally, the logic one out-put level 141 is shown as being less than the supply voltage, V (131), and greater than one-half of-the supply voltage, 1/2 V (132). The logic zero level 140 is shown as being greater than zero volts but less than one-half of the supply voltage, 1/2 V (132). In thi~
manner, the signal can be seen to "straddle" the one-half supply voltage level.
After operation of the d.c. restorer circuit, the loyic zero level 145 of the resulting waveform is near to the zero voltage reference, as depic~ed in Fig. 10. In addition, the resulting logic one level 135 is substantially equal to one-half of the sup-ply volta~e, 1/2 V ~13~).
This resultin~ signal is then amenable to processing bythe Schmitt trigger portion of the circuit as previously described~
Depicted on Fig. 10 are the relative voltage levels C and D relat-ing to the break points of a typical Schmitt trigger ~tage. As can 3n be seen, this resulting wave~orm is read~ly a~enable to ~roce~sing by such Schmitt trigger devices in order to ~ccurately indicate the transition points relating ~he desired position data.

-25b-Fig. 11 shows the spec~ally designed 29 facet stepped echelon mirror assembly ln which the peaks of the mirrors a~ a constant dimension from one another in succes-; sion, here 0,2 inches.
In the embodiment of Flg~ 11, the following angular relationships exist:
All beta angles = 90 degrees alpha deg. min. alpha deg. m~n. alpha deg. min.
1. 2715 11. 34 10 21. 41 10 2800 12. 34 55 22. 41 S0

3. 2840 13. 35 35 23. 42 30

4. 2920 14. 36 2~ 24. 43 15

5. 3000 15. 37 00 25. 43 55 .
: 6. 3045 16. 37 40 ~6. 44 35 7~ 3125 17. 38 20 27. 45 20 8. 3205 18. 39. 05 28. 46 00 ~ 32;50 lg. 39 45 29. 46 40 1~. 3330 20. 40 25 In Fig. 12 of the drawings, an 18 facet stepped echelon miero~ is shown ~n whlch peaks are spaced 0.375 inches apart. ~n Fig. 12, the angles are as follows:

~2 ~
All be~a angles ~ 90 degrees alpha deg. min~ alpha deg. min. alpha deg. min.
1. 16 56 7. 3~ 44 13. 40 34 2. 20 5~ 8. 34 20 1~. 41 34 3. 24 05 9. 35 47 15. 42 30 4. 26 ~2 10. 37 08 16. 43 23 5. 28 58 11. 38 22 17. 4~ 1~

6. 30 57 12. 39 30 1~. 45 00 . It should be realized that facets such as 191 in Fig. 11 or 155 and 156 in Fig. 12 can be substantially planar in form or cu~ved as shown in phantom, so as to ~focus" the light reflected the~eby. Addit~onally, the number of surfaces being utilized in a part~cular application can be opt~mized relative to produce-ability, economics, edge losses, resolution and echelon assembly depth. However, ~he particular design of Fig. 11 makes possible a linear output di~play due to the capab~lity of the detector-scanner to ~review" or focu~ upon respective equivalent distances across ~he locatlon region window as a function oE re~pective sub~antially equivalent radial scan angle~. The partlcul~r con-~truc~ion of this stepped e~helon mirror assembly also makes ; po~s1ble the control of inten~ity so that intens~ty is substan-~ially equival~nt acros~ ~h~ window 21 regardless of the coordlnate position being review~d. For sha'1owe_ nir--o-c -han th2r of Fig. 11, such as Fig. 12, a trignometric or other function must be used in conjunction with the display device since the location of an object will now be a non-linear function of the radial scan angles at which the object is detected.
In terms of resolution, it is necessary to develop pitch spacing between the facets of a particular mirror assembly which ls smaller than the smallest object desired to be resolved. Alternatively, the mirror facets can be skewed to parallelogram form -to eliminate shaclows.

~ 2~L2,~
Specifically, as shown in Fig. 16, minor shadow ~ ions 253 may occur between the reflective regions 254. Such shadow regions may result from element-to-element shading of the individual mirror face~s, or frorn edge effects of the Presnel mirror configuration. No radiant energy is transmitted or recei~ed in association with these shadow regions. Al~hough the shadow regions 253 are o~ little consequence with respect to objects which have dimensions substantially greater than the width of the shadow re-gions 253, it may be possible for narrow objects to fall completely ] withln such a shadow region and thereby go undetectedO For example, if object 52 is inserted within the reflective region 254a of the standard stepped echelon mirr~r shown in side view in Fig. 16~a~, it will res~lt in a light blockage corresponding to shaded region 263, and will be detected. However, if the item i6 inserted into one of the shadow regions 253, no light blockage results, as shown by region 264, and the object will not be detected.
In order to overcome the possibility of objects which are perpendicular to the location region 21 going unnoticed, the indi-vidual mirror elements may be skewed such that the faces of the facets fonn parallelogra~s as shown in side view in Fiq. ~6tb).
~y selection of an appropriate skew angle, it is possible to cre-ate a configuration s~ch that even narrow objects will provide at least partial blockage of one or more reflective areas 253b, as shown by shaded region 265, even if other portions of the object 25 fall within the shadow regions 254b, such as region 266. Excess~
ive skew, however, may result in decreasad accuracy and resolution, for all objects inserted may then lntercept tw~ adjoining regions.
This is illustrated by Fig. 16~c~, wherein object 52 will be detec-ted within two adjoining regions as a result of areas 267, with region 268 being unregistered. Preferably the skew of the mirror facets of the detectors is designed to be the equivalent mirjror in,age of the skew of the facets of the distributors such that light bearns of parallelogram cross-section are distributed and receivecl.
Ilowever configurations are possible, for example an opposite relat:ive skew to the facets of the collector provicles Eurther blending.
-27a-In another embodiment of the invention, optic~l ele~ment 57 is stationary facing toward ~hield 29 and shield lB is removed. Mask 61 is not re~uired~ Detector 60 is Fairchlld Semiconducto~ CCDllO 'Linear Image Sensor' or equivalent, and in combination with appropriate circuitry and element 57 con-~titutes both selective viewing means and datection means.
In another embodiment of the invention, the means for selectively viewing portions of transferred radiant energy occurs at other locations along the radiant energy ~ransmission path.
For example, instead of utilizing a rotat~ng "scanner-detector", as previously described, a stationary detector may be utilized with a projecting-scanner-emitter. Referring to Fig. ~, in the scanner-emitter embodiment, former photocell 60 becomes light-so~rce 60, wi~h elements 61, 62 and 53 through 57 assuming the same structures as previously described.
Scanner-emitter 48 would replace scanner-detector (4B~
be~ween banks 41 and 42 to transmit radiant energy across "window"
21 in a directio~ opposlte to the arrow heads shown in Fig. 1.
Transmissions and~or alterations in the energy thus transmitted are plcked up by stationary photocell assembly 28 within shields 27 and 2~. In thls embodiment, the collector assemblies become distributor assemblies and vice ver~a.
Altecnatively, electrochemical, elec~romechanical, mechanical, or ele~.ronic shutter means ~uch as liquid c~ystal display elements or aperture slo~s moved by loud speaker 9 sole-r.oid, or piezo-~lectric ceramic transducers, may be interposed at appropria~e pos~tlon~ along the radiant energy transmission path, to enable selective viewing of the transm$tted rad~ant energyemissions. Fig. 17 illustrates such an alternative embodiment utilizing an electronic shutter means cooperating with -the detector. Liquid crystal stripe filters 270 are located within the path of the radiant energy beams. As shown in Fig. 18, the stripe filters comprise a multiplicity of parallel, adjacent transmission-type liquid crystal elements 271. These individual stripes are oriented to lie in op-tical alignment between D 77 ~
the radiant en~rgy detect~r and the collectors 42 41 such that each indlvidual mirror facet of collectors 42~ 41 is ~n align-ment with one or more of the filter stripes 2~1.
In operation, a single element, such as element 272, is ren~
r dered tran~parent to ~he radiant energy while other elements 271 are rendered opague to such energy. Thus, the transmitted radiant energy is ab50rbed by stripe filter 270, with the exception of that portion of such energy which corresponds to a single location beam 273. By successively causing individual elements 271 to be sequen-ti~lly rendered transparent in this manner, an electronic scan of the reoeived radiant energy results.
In the ~mb~diment illustrated in Fig. 17 stripe filters 270 are located proximate to the detector near the point of convergence of the light beams. In this manner, the linear dimen-sions of the stripe filter 270 may be held to a minimum, thereby reducing production costs. In addition, as illustrated in Fig. 18"
in the preferred embodiment the liquid crystal stripe filter 270 is plated for insertion into cooperating socket 277. Drive electronics 274 are mounted proximate to socket 277 and connected by printed circuit wiring 276 applied to the mounting suLstrate 275, resulting : in united, inexpenslve construction~ The liquid crystal stripe fllters 270 may be either multiplexed or direct drive types.
The drive electronics 274 cause an element-by-element ~can f irst of the liquid crystal stripe filter 270 located within the x axis rad~ant energy field, and then of the corresponding fllter 270 located within the y-axis field. This operation may be repeated continuou31y, allowin~ light from only a single x- or y-axis relative position to reach ~he detec~or at a glven time. In this manner, only a ~ingle radiant eneryy detection element need by utilized. ~l~erna~ively, the stripe ~ilters 270 may be simultaneously scanned~ with individual detectors utilized in conjunction with each to simultaneously de~ermine both the x-and y-coordinate positions. Scan rates of twice the fre~uency are thus posslbl~.

-~aa-Fig. 13 represents yet anoth~r embodiment o the present apparatus wherein a plurality of light emitting diodes are provided which function as both the radiant energy emission means and as the distributor means. Specifically, a multiplicity of light emitting diodes are arranged along each of two of the axes of ~he location region window 18~ such that the radiant energy output of the devices is transmitted in substantially parallel beams across ~he location window 186. These diodes are represented in Fig. 13 by, for exam-ple, LED 163, 164, 165, 166, 167 and 168. The beams 50 generated may be further columnated by utilization of picket frame 181, con-taining a pl~rality of apertures 180. ~ntegrated collector banks161 and 162 serve to equiv~lently reflect transmitted light, (or the absences thereoE) to detection device 132 which consists of back-to-back photodetectors 183 and 184. Picket frames 181, which could be macro or micro louvers and which completely encircle the location region 186, serve to restrict the emitted light into parallel beams.

In order to selectively view or scan portions of the radiant energy and to establish a frame of reference relative to which one of the LED beams is being blocked, should an object appear within window 186, the LEDS themselves are pulsed in successive order at a desired rate to create a scan-time signal similar to that of the embodiment of Fig. 1. Through such a technique, as well as through the alternative use of a scanner-emitter or strlpe filter mask scanners only one or two photodetector devices are required to "interpret" the transmission and alteration characteristics resulting from the location of an object within location region 186.

~ 29-As previously noted the seanner deteetor appara-tus may be operably coupled through the signal proeessing means to visual display means for visual interpretation of radiant energy being seanned and deteeted thereby. Fig. 19 illus-trates a means for visually displaying the output data of optical position location device 20. Specifically, outputs of the device such as those shown in Fig. 5 may be supplied to the input of an oscilloscope 222 by means of input lines 225.
To achieve a stable, constantly updated display, the oscilloscope 222 is repetitively triggered at the same point on each successive output waveform and this may be aecomplished by use of a synchronization signal extractor circuit 221, whose output is supplied by means of sync lines 224 to the synchronization signal input of oseilloscope 222. A stable representation 223 of the output waveform is thereby displayed on the face of the oseilloscope cathode ray tube, from which desired data may be measured.

~2~

In addition to determining the location and size of an object relative to the coordinate axes of the device, the present invention as previously noted is capable of approximating the height of objects which are shorter than S the depth of the measuring field itself or alternately the depth of penetration of an opaque object. Such determinations may be extrapolated from data pertaining to the in-tensity of the received signals. As shown in Fig. 20, the individual lig~t rays which comprise the location determining rays previously discussed may have a fixed and significant "thickness" or depth normal to a plane described by the measurement axes themselves. This may be on the order of .3 to .5 inches, although it will be seen that o-ther depths are possible (e.g. due to "stacking" of devices as previously noted). The light which is distributed by, for example, distri-butors 4n and 32 o~ Fig. l may preferably h~ve substantially equal intensity throughout the depth of the resulting beams. In this manner, for opaque objects wlder than the particular light beam, the ~ntensity of the unblocked light which is ~eceived by the de-tector will corre~pond inversely to the average depth of pene~ra-tion of the object. For example, ob~ect2~ob inserted approximate hal~way into the location region 21 will intercept approximately one-half of the incident light rays 242, ~nd correspondln~ly will permit the remaining one-half of the light ray~ 243 to pass to th~
detector~ As shown in Fig. 21 the resulting outputs 200b, 201b corre~ponding to the unobstructed portion 243 of the incident light 242 will have a correspondingly reduced level when compared to the output 200a~ 2~1~ which would result ~rom complete blockage such ~s by item ~Old.

SUPPLEMENTARY DISCLOSURE

In addition to the pre~ious disclosure, certain other embodiments or aspects of the invention are intimately associat-ed w.ith the description of the invention as framed previously.
These additional embodiments or aspects are detailed herein in conjunction with additional drawing figures wherein:

.

~ ~%~

Fig. 22 is a side elevational view of an alternative embodiment of the optical ~lement of Fig. 17;
Fig. 23 is a circuit diagram of the syncronization signal extraction circuit of Fig. 19;
Fig. 24 is a side elevational view of one embodiment of the optical position location apparatus used in con-junction with a television monitor as a data input device;
Fig. 25 depicts use of a television monitor to display positional data derived from the position location apparatus;
Fig. 26 is a circuit diagram of an alternative embodiment of a portion of the amplifier circuit of Fig. 6;
Figure 22 shows a preferred embodiment for a single detector configuration for use in conjunction with, for ex-ample, the electronic scanner shown in Fig. 17. An optical element 256 intercepts radiant energy which passes through the transparent elements of stripe filters 270, and re-flectively and refractively transmits such energy to detector 277. Optical element 256 is preferably made of plastic, such as acrylic which has an index of refraction of approximately 1.5. Other plastics or glass may be used.
Optical element 256 comprises a sphere 281 into which a 45 cone 280 is milled. The resulting conical surface of cone 280 is preferably optically polished.
The light passed by the stripe filters 270 strikes element 256 and is refracted by the spherical element 281, striking the surface of the milled cone 280. Because of the differences in indexes of refraction of the material of sphere 281 and the ambient air, total refraction occurs at the surface of cone 280, thereby directing the light sub-stantially axially through sphere 2Bl. rrhis light is further refracted by sphere 281, and is focused thereby onto the detection element 277. Because of the radial symmetry of optical element 256, light ~rom any radial direction is similarly refracted and reflected axially and detected by element 277. Alternatively, other methods known in the art may be utilized to collect and detect the radiant energy passed by stripe filters 270. The detector configur-ation shown in Fig. 22 may be used in the embodiment shown in Fig. 13.
With reference to the syncronization signal extractor circuit 221 of Fig. 19, a preferred embodiment of the circuit is shown in Fig. 23. The circuit includes a negative inte-grator comprising amplifier 230, feedback resistor 233 in parallel with feedback capacitor 232, and input resistor 231. The negative integrator is connected to a detection and peak clamping circuit comprising transistor 239, storage capacitor 236, and bleed resistor 237. The output is generated across collector resistor 235.
In operation, the output of amplifier 230 is initially at a high, positive level. Upon application of a positive input, the negative integrator performs a negative time average integration of the input signal, resulting in a declining output voltage from amplifier 230. The values of input resistor 231, feedback resistor 233, and feedback capacitor 232, as well as the gain of amplifier 230, are selected so that the saturation time of the resulting negative integrator is somewhat greater than the duration of the longest high-level input expected. As shown in Fig. 8, such high-level inputs result when the light is blocked from the detector element, such as by shield 18 of ~ig. 1.
In the preferred embodiment, the longest duration high-level input will correspond to light blockage caused by one of the light blocking shields, such as by shield 18 of Fig. 1.

Peak storage capacitor 236 is charged positively by bleed resistor 237. The time constant of the resulting circuit is chosen to be substantially greater than the dur-ation of a full rotation of the optical scanner. In the preferred embodiment, this time constant may be 10 times the duration of a single rotation. In this manner, bleed resistor 237 will not cause the voltage of storage capacitor 236 to change appreciably during a single cycle of the circuit operation.
In addition to serving in conjunction with capacitor 236 and resistor 237 as a peak holding circuit, transistor 234 serves as a detector element. Specifically, the syncroni-zation signal extractor circuit is designed to recognize the longest duration high-level input corresponding, as discussed, to one of the light blocking shields. This longest duration input causes the output of amplifier 230 of the negative integrator to reach its lowest level of output. At this time, transistor 234 turns on briefly, restoring the peak level to capacitor 236. In addition, the resulting collector curxent through collector resistor 235 causes an output voltage signal which may be utilized to trigger oscilloscope 222. In this manner, an identical reference point within each succeeding waveform is established.
Fig. 24 depicts use of the optical position location apparatus 20 in conjunction with a television monitor 201 to create an interactive data input device. Specifically, apparatus 20 is mounted directly to the front surface of monitor 201 such that the toroidal housing 20a surrounds the television screen 209. The output 204 of the apparatus is in one embodiment connected by means of lead 207 directly to the input 205 of a microprocessor system 202. Alternative-ly, a programmable interval timer 203 may be inserted between !~ ~
`~`1~

~2~

points A and B of Fig. 24, such that the device output 204 is supplied to the programmable interval timer 203, and the output of such interval timer 203 is then applied to the microprocessor input 205. Finally, the interactive loop is completed by supplying the television monitor 201 with an appropriate output 206 generated by the micro-processor 202.
In use, the microprocessor 202 presents, for example, a menu of selections to the monitor 201. These selections appear as identified regions 208, 211 on the television screen 209. The user may then select among these options and indicate a finger 210. Alternatively, a suitabie stylus may be used.
When the user's finger 210 touches the television screen 209, it also is interceding within the location region 21 of the position apparatus 20. Data corresponding to the location of this interceding object 210 is trans-mitted to appropriate analyzin~ circuitry. In one embodiment, the output goes directly to the microprocessor 202. In another embodiment, a programmable interval timer 203 is inserted. The interval timer 203 ~enerates outputs corresponding to the respective lengths of the llonll and "off"
portions of the signal received. As previously discussed, these "on" and "off" time periods correspond to the location and size of the interceding object 210. Although the micro-processor 202 may perform the requisite timing interpretations itself, use of a programmable interval timer 203 may be preferable in order to reduce computational overhead of the microprocessor 202.
By correlating the received data pertaining to the location of object 210 and the displayed menu selections 208, 7Jr~i 211, the microprocessor may determine which of the selections has been chosen, and an appropriate response may be initiated.
In a preferred embodiment, the selection chosen may be highlighted as shown by menu element 211 in order to provide visual feedback to the operator that a selection has been, or shortly will be, recognized by the microprocessor 202.
In this manner, an inexpensive yet extremely flexible and user-friendly data input or programming device results which frees the user ~rom the need for cumbersome, confusing or 10 intimidating keyboard input.
Under certain circumstances it may be desirable to have available a display corresponding to the location of an interceding object other than that previously described. In one embodiment shown in Fig. 25, an interface 220 is provided 15 which generates an output on television monirot 201 corresp-onding to the positioned location of an interceding object 210. For example, that portion Z12 of the television picture corresponding to the location of any interceding object 210 may be hi~hlighted. In this manner, a direct graphic 20 representation o both -the size and location of any inter-ceding objects results.
When the heights of objects or the depth of penetration is extrapolated from data pertaining to the intensity of received signais as shown in ~igs. 20 and 21, the analog 25 d.c. level of signals 200~ 201 should be retained and therefore, in the preferred embodiment for use in conjunction with depth o~ penetration indication, the Schmitt trigger as shown in the circuit in Fig. 6 is replaced by the circuit shown in Fig. Z6. Specifically, inverters 99 and 100 a~e 30 configured as linear amplifier stages by use of input resistors 98, 251, and feedback resistors 250, 252, respect-ively. Output resistor 102 is retained, although bypass ~esistor 94 is deleted. The resulting linear circuit is ~12~ f~
inserted between nodes before resistor 98 and after resistor 102 in Fig. 6 in lieu of the Schmitt trigger configuration~
Finally, it may be desirable to utilize techniques known in the art to provide for automatic gain control and compensation of the linear ou-tput data, in order to correct for variations in the output of the radiant energy emission means 28. The previously discussed calibration beams ; passing external to the location region 21, corresponding to offset regions 121_ 125 of Fig. 8, may advantageously be utilized for this purpose.
The foregoing description and drawings including the Supplementary Disclosure merely explain and illustrate the invention; and the invention is not limited thereto, except insofar as the appended claims are so limited, as those skilled in the art who have the disclosure before them will be able to make modification and variations therein without departing from the scope of the invention.

-3~-

Claims (80)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. An optical position locating apparatus for locating the position of one or more objects along one or more coordinate axes of a defined area, as well as for determining other measurable parameters of said one or more objects such as the sizes thereof relative to said one or more coordinate axes, said apparatus comprising:
radiant energy emission means;
radiant energy detection means;
distributor means for distributing said radiant energy emitted by said radiant energy emission means over a location region from a position along a first portion of said region;
one or more integrated collector means positioned along a second portion of said location region which is substantially opposite said first portion of said location region, and cooperating with said distributor means to receive said radiant energy distributed by said distributor means and to transmit said radiant energy to said radiant energy detection means; and means for selectively viewing portions of said distributed and received radiant energy to disclose properties of said radiant energy which have been altered as a result of said object being located within said location region so as to, in turn, determine the location of said object within said location region, as well as said other parameters of said object.

2. An optical position location and size determining apparatus for locating the positions of one or more objects along one or more coordinate axes of a defined sensing area, as well as for determining other measurable parameters of (claim 2 cont'd) said one or more objects such as the sizes thereof relative to said one or more coordinate axes, said apparatus comprising:
radiant energy emission means;
radiant energy detection means;
means for distributing said radiant energy emitted by said radiant energy emission means over a location region from a position proximate to a first side of said region;
one or more integrated collector means proximate to a second side of said location region, said integrated collector means cooperating with said distributor means to receive said radiant energy distributed by said distributor means and to transmit said radiant energy to said radiant energy detection means;
signal output means operably connected to said radiant energy detection means;
shield means, said shield means to prevent ambient or stray radiant energy not transmitted from said integrated collector means from impinging said radiant energy detection means;
scanner means;
said scanner means including optical element means, said optical element means operating to direct said radiant energy received from said integrated collector means to said radiant energy detection means;
said scanner means further including motor means, said motor means being operably connected to said optical element means whereby said optical element means is made to rotate with respect to said integrated collector means;
said scanner means further including apertured mask means, said apertured mask means having a dimensioned aperture therein;

said apertured mask means cooperating with said optical element means and located in optical alignment with said optical element means and said radiant energy detection means;
said shield means and said scanner means cooperating to restrict the radiant energy received by said radiant energy detection means to that portion of said distributed radiant energy received by the portion of said integrated collector means which is instantaneously in optical alignment with the combination of said rotating optical element means, said dimensioned aperture of said apertured mask means, and said radiant energy detection means, whereby the radiant energy received by said integrated collector means may be sequentially and selectively monitored by said radiant energy detection means.

3. The invention according to claim 1 or 2 wherein said radiant energy emission means, said distributor means, said integrated collector means, and said radiant energy detection means are operably positioned within an enclosed housing member;
said location region comprising a substantially apertured area defined by said housing member.

4. The invention according to claim 1 or 2 wherein the apparatus includes one said radiant energy emission means, one said distributor means, one said integrated collector means, said radiant energy detection means determining the location and/or other parameters of one or more objects along one coordinate axis in one dimension.

5. The invention according to claim 1 wherein said apparatus includes two substantially separate distributor means, two substantially separate integrated collector means respectively aligned with said two distributor means, said radiant energy detection means determining at least the location of one or more objects along two coordinate axes in two dimensions.

6. The invention according to claim 5 wherein radiant energy emitted by said radiant energy emission means and distributed across said location region for collection and detection thereof is optimized to disclose not only location and size of an object along said two dimensions, but also for disclosing the height of an object as a function of the intensity disclosed by received radiant energy through said detection means.

7. The invention according to claim 5 wherein said apparatus comprises a plurality of aligned and stacked two dimensional distributor means and integrated collector means for locating one or more objects, as well as other parameters of said one or more objects in three dimensions.

8. The invention according to claim 2 wherein said apparatus includes two substantially separate distributor means, two substantially separate integrated collector means respectively aligned with said two distributor means, and radiant energy detection means for determining the location and/or other parameters of one or more objects along two coordinate axes.

9. The invention according to claim 1 or 2 wherein said radiant energy comprises unpolarized electromagnetic light.

10. The invention according to claim 1 wherein said means for selectively viewing a portion of said radiant energy comprises a light projecting scanner-emitter which rotates relative to said distributor means to selectively transmit light at different locations across said location region.

11. The invention according to claim 10 wherein said detection means comprises photodetector means cooperating with said collector means;
said photodetector means producing electrical responses relative to the radiant energy received, thereby disclosing the existence of any alterations of radiant energy properties corresponding to objects in said location region;
the instantaneous angular position of said scanner-emitter at the time of occurrence of said electrical response being functionally related to the position of said object within the location region.

12. The invention according to claim 1 wherein said radiant energy emission means comprises a plurality of individual radiant energy sources, and in which said distributing means comprises the mounting of said individual sources in spaced relationship along said first portion of said location region whereby a plurality of substantially discreet beams results.

13. The invention according to claim 12 wherein each of said plurality of said radiant energy sources comprises a light emitting diode.

14. The invention according to claim 13 wherein said detection means comprises a single photo-sensitivs cell cooperating with said collector means across said plurality of light emitting diodes;
said means for selectively viewing portions of said distributed and received radiant energy emissions comprising pulsation of each of said light emitting diodes;

said photo-sensitive cell being capable of generating electrical responses relative to radiant energy transmitted from said light emitting diodes to disclose altered light transmission properties to, in turn, describe the location of an object within said location region, as a function of time as said light emitting diodes are pulsed.

15. The invention according to claim 1 wherein said means for selectively viewing portions of said radiant energy includes scanner means which rotates relative to said collector means to selectively transfer to said radiant energy detection means radiant energy received by said collector means from specific locations of said location region.

16. The invention according to claim 2 or 15 wherein said radiant energy emission means comprises substantially stationary continuously emitting light source means.

17. The invention according to claim 15 wherein said scanner comprises:
shield means to absorb radiant energy not transmitted from respectively integrated collector means;
motor means operably connected to an optical element for rotating same;
an apertured mask cooperating with said optical element;
said apertured mask having a dimensioned aperture to describe that portion of transferred radiant energy detected at one point during the rotation of said scanner means, and in which said detector element is operably positioned in alignment with said optical element and said apertured mask;
said radiant energy transferred from said integrated collector means entering said optical element, being reflected through said apertured mask, in turn, to the surface of said detection element;
said rotating optical element and mask permitting said scanner assembly to scan portion by portion, across one coordinate axis of the location region described by one respective integrated collector and then, in turn, to scan across each one of said remaining coordinate axes described by said remaining ones of said one or more collector means, in successive repetition.

18. The invention according to claim 2 or 17 wherein said optical element comprises a sphere having fabricated therein a substantially diagonal-cut plane portion for reflection of radiant energy into and through said dimensioned aperture of said apertured mask.

19. The invention according to claim 2 or 17 wherein said detection means comprises photocell means.

20. The invention according to claim 15 wherein said emission means includes blockage means to intercept and absorb radiation directed to locations other than those occupied by said distributor means.

21. The invention according to claim 17 wherein said apparatus further includes amplifier means;
said motor means being coupled to said radiant energy emission means, to said radiant energy detection means, and to said amplifier means in an electrical circuit said motor means further including electrical filter means in parallel connection therewith to reduce commutator noise from said motor means;
said motor means further including speed control means to produce a desired rotational speed in said motor means;

said motor means further being connected in parallel connection to said amplifier means; and said amplifier means being operably connected to said radiant energy detection means to receive signals therefrom.

22. The invention according to claim 21 wherein said amplifier responds to the intensity of current through said detection means;
said detection means comprising a photo-sensitive diode;
said amplifier means further comprising gain means with noise suppressant means to transduce between the variable current of the photo-sensitive diode into a resulting voltage signal;
d.c. restorer means coupled to said gain means for restoring the d.c. level of signal; and Schmitt trigger means for quantizing the signals thus removing noise.

23. The invention according to claim 2 or 15 wherein said detection means is operably coupled via signal processing means to visual display means for visual interpretation of the radiant energy being scanned and detected by said detection means cooperating with said scanner means.

24. The invention according to claim 2 or 15 wherein said radiant energy detection means is operably coupled via signal processing means to cathode ray visual display apparatus for visual interpretation of the radiant energy being scanned and detected by said radiant energy detection means cooperating with said scanner means.

25. The invention according to claim 1 or 2 wherein the apparatus further comprises radiation filter means interposed between said distributor means and said integrated collector means for the purpose of precluding interference from light and other radiant energies of wavelengths other than those of the intended radiant energy being emitted, distributed and collected for detection.

26. The invention according to claim 1 or 2 wherein said apparatus further comprises a red and infrared passage filter interposed between said distributor means and said integrated collector means for the purpose of precluding interference from light and other radiant energies of wavelengths other than those of the intended radiant energy being emitted, distributed and collected for detection.

27. The invention according to claim 1 or 2 wherein said distributor means distributes radiant energy at positions outside of said location region so as to describe radiant energy transmission routes which cannot be altered or broken by objects located within said location region, the radiant energy traversing the resulting unalterable radiant energy transmission routes and detected by said radiant energy detection means thereby creating reference signals defining fixed and known positions relative to said location region.

28. The invention according to claim 1 wherein at least one of said distributor means comprises a stepped echelon mirror assembly;
said stepped echelon mirror assembly comprising a plurality of faceted mirror elements;
said faceted mirror elements being individually oriented with respect to said radiant energy emission means and said location region to receive a portion of the radiant energy emitted by said radiant energy emission means and thereafter transmit it across a select portion of said location region.

29. The invention according to claim 1 wherein at least one of said integrated collector means comprises a stepped echelon mirror assembly;
said stepped echelon mirror assembly comprising a plurality of faceted mirror elements;
said faceted mirror elements being individually oriented with respect to said location region and said radiant energy detection means to receive radiant energy from a select portion of said location region and thereafter transmit it to said radiant energy detection means.

30. The invention according to claim 1 wherein one or more of said distributor means and collector means comprises a stepped echelon mirror assembly for receiving said reflecting radiant energy within said optical position location apparatus;
said stepped echelon mirror assembly comprising a plurality of faceted mirror elements for transferring portions of reflected radiant energy in a non-linear relation for the selective viewing of said distributed radiant energy by said detection means.

31. The invention according to claim 1 wherein one or more of said distributor means and collector means comprises a stepped echelon mirror assembly for receiving and reflecting radiant energy within said optical position location apparatus;
said stepped echelon mirror assembly comprising a plurality of faceted mirror elements for transferring portions of reflected radiant energy in a linear relation for the selective viewing of said distributed radiant energy by said detection means.

32. The invention according to claim 31 wherein said stepped echelon mirror assembly comprises 29 substantially individual faceted mirror elements;
each of said 29 faceted mirror elements being 0.2 inches width with respect to a datum line defining a linear axis; and said faceted mirror elements ranging in depth relative to a datum line parallel to said linear axis and contiguous to the outermost edge of the outermost extending faceted mirror element, a distance ranging from 1.617 inches to 0.171 inches, in substantially curvilinear fashion.

33. The invention according to claim 1, 28 or 29 wherein one or more of said distributor means comprises refractive means positioned along said first portion of said location region;
said radiant energy being distributed over said location region by refraction thereof.

34. The invention according to claim 1, 28 or 29 wherein one or more of said integrated collector means along said second portion of said location region comprises refraction means;
said radiant energy being received and transferred to said detection means by refraction thereof.

35. The invention according to claim 1 wherein said means for selectively viewing portions of said distributed and received radiant energy includes electronic shutter means interposed along the path of said radiant energy transmission, said electronic shutter means operably exposing said radiant energy detection means to radiant energy transmitted across individual selected positions of said location region.

36. The invention according to claim 35 in which said electronic shutter means comprises a transmission-type liquid crystal stripe filter, said filter comprising a plurality of adjacent, parallel filter elements which may individually be rendered substantially opaque or substantially transparent by associated drive electronics.

37. The invention according to claim 1 wherein said means for selectively viewing portions of said distributed and received radiant energy comprises mechanical shutter means interposed along the path of said radiant energy transmission, said mechanical shutter means operably exposing said radiant energy detection means to radiant energy transmitted across individual selected portions of said location region.

38. The invention according to claim 37 wherein said mechanical shutter means comprises an apertured slot assembly operably controlled by shutter control means.

39. The invention according to claim 1 or 2 wherein one or more of said distributor means and integrated collector means comprises a stepped echelon mirror assembly for receiving and reflecting radiant energy;
said one or more stepped echelon mirror assembly including substantially curved mirror surfaces in order to maximize radiation transfer by focusing said radiant energy as it is reflected.

40. The invention according to claim 1 wherein said detection means and said means for selectively viewing portions of said distributed and received radiant energy are integrated into a substantially singular component, said singular component comprising a linear image sensor.

41. The invention according to claim 28 wherein reflective surfaces of said faceted mirror elements comprise longitudinally skewed parallelograms with vertical sides transversely angled to said axes, whereby adjacent reflected beams overlap relative to a datum normal to the plane described by the coordinate axes of the distributing means and collector means, resulting in substantially continuous illumination across the location region.

42. The invention according to claim 29 wherein reflective surfaces of said faceted mirror elements comprise longitudinally skewed parallelograms with vertical side transversely angled to said axes, whereby adjacent received beams overlap relative to a datum normal to the plane described by the coordinate axes of the distributing means and collector means, resulting in substantially continuous monitoring of the location region.

43. The invention according to claim 15 wherein said scanner means comprises:
optical element means, said optical element means directing said radiant energy received from said collector means to said radiant energy detection means;
motor means, said motor means operably connected to said optical element means whereby said optical element means is made to rotate with respect to said collector means;
said rotating optical element means thereby scanning portion-by-portion across one coordinate axis of said location region described by one respective collector means and then, in turn, scanning across each of the remaining coordinate axes described by the remaining collector means, in successive repetition.

44. The invention according to claim 43 wherein said scanner means further comprises means for view restriction, said view restriction means cooperating with said optical element means to restrict the portion of radiant energy received by said radiant energy detection means to a defined beam;
said beam comprising only the radiant energy received by that localized portion of said collector means which is instantaneously in optical alignment with the combination of said rotating optical element means, said view restriction means, and said radiant energy detection means;
the radiant energy received by individual localized portions of said collector means being thereby sequentially and selectively monitored by said radiant energy detection means.

45. The invention according to claim 44 wherein said view restriction means comprises apertured mask means;
said apertured mask means having a dimensioned aperture therein and located in optical alignment with said optical element means and said radiant energy detection means.

46. The invention according to claim 43 wherein said scanner means further comprises shield means, said shield means substantially preventing radiant energy approaching from positions other than those associated with said collector means, from impinging said optical element means and reaching said radiant energy detection means.

47. The invention according to claim 43 in which said optical element means comprises a substantially spherical element having fabricated therein a substantially diagonal-cut plane portion for redirecting said received radiant energy to said radiant energy detection means.

48. The invention according to claim 43 in which said radiant energy detection means comprises a silicon photocell.

49. The invention according to claim 43 in which said radiant energy detection means comprises a photodiode operated in the reverse biased mode.

50. The inveniton according to claim 2 wherein one or more of said one or more distributor means comprises a stepped echelon mirror assembly;
said stepped echelon mirror assembly comprising a plurality of faceted mirror elements;
said faceted mirror elements being individually oriented with respect to said radiant energy emission means and said location region to receive a portion of the radiant energy emitted by said radiant energy emission means and thereafter transmit it across a select portion of said location region.

51. The invention according to claim 2 wherein said radiant energy detection means comprises solid state photo detector means.

52. The invention according to claim 50 wherein said faceted mirror elements are oriented with respect to said radiant energy emission means and said location region such that the radiant energy emitted by said radiant energy emission means is transmitted across said location region in substantially parallel beams spaced substantially evenly across said location region.

53. The invention according to claim 52 wherein each of said faceted mirror elements receives a substantially equal portion of radiant energy from said radiant energy emission means.

54. The invention according to claim 2 wherein one or more of said one or more integrated collector means comprises a stepped echelon mirror assembly;
said stepped echelon mirror assemly comprising a plurality of faceted mirror elements;
said faceted mirror elements being individually oriented with respect to said location region and said radiant energy detection means to receive radiant energy from a select portion of said location region and thereafter transmit it to said radiant energy detection means.

55. The invention according to claim 50 or 54 wherein one or more of said faceted mirror elements include curved mirror surfaces for providing reflective focusing of the radiant energy.

56. The invention according to claim 54 wherein said faceted mirror elements are oriented with respect to said location region and said radiant energy detection means such that said faceted mirror elements individually receive radiant energy from portions of said location region which are substantially parallel to one another and which are spaced substantially evenly across said location region.

57. The invention according to claim 56 wherein each of said faceted mirror elements is within optical alignment with said optical element means of said scanner means for substantially equal portions of the rotation of said rotating scanner means, and wherein the incremental angular separation between the peaks of each said faceted mirror elements corresponds to substantially equal angular portions of the rotation of said rotating scanner means, whereby a substantially linear relationship exists between the instantaneous angular position of the optical elements means of the rotating scanner means, and the traverse location of that select portion of said location region from which radiant energy is being instantaneously received by said radiant energy detection means via said stepped echelon mirror assembly.

58. The invention according to claim 57 wherein said stepped echelon mirror assembly comprises 29 substantially individual faceted mirror elements;
each of said 29 faceted mirror elements being 0.2 inches wide with respect to a datum line defining a linear axis; and said faceted mirror elements ranging in depth relative to a datum line parallel to said linear axis and contiguous to the outermost edge of the outermost extending faceted mirror element a distance ranging from 1.617 inches to 0.171 inches, in substantially curvilinear fashion.

59. The invention according to claim 1 wherein said invention further includes signal output means, comprising:
detector buffer means, said detector buffer means responding to an electrical output signal of said radiant energy detection means and generating a corresponding buffer output signal; and output discriminator means, said output discriminator means connected to the output of said detector buffer means whereby said signal output means responds to said buffer output signal to create a device output signal representative of the altered parameters of said received radiant energy.

60. The invention according to claim 59 wherein said detector buffer means comprises:
amplifier means;
said amplifier means generating said buffer output signal, said buffer output signal comprising a first variable voltage output signal;
said amplifier means including gain determining means;
said amplifier means further including electrical filter means for suppressing input signals of undesired frequencies.

61. The invention according to claim 59 wherein said signal output means comprises output discriminator means;
said output discriminator means producing a first given discriminator output signal when said buffer output signal corresponds to the absence of an object within said relevant portion of said location region; and said output discriminator means producing a second given discriminator output substantially distinct from said first given output signal when said buffer output signal corresponds to the presence of an object within said location region.

62. The invention according to claim 61 wherein said output discriminator means comprises d.c. restorer means;
said d.c. restorer means designed to add or subtract a given voltage to said buffer output signal, producing a d.c. restored signal;
said output discriminator means further comprising Schmitt trigger means;
said Schmitt trigger means producing a first, logic-one level output when said d.c. restored signal rises above a first predetermined voltage level, and producing a second, logic-zero level output when said d.c. restored signal falls below a second predetermined voltage level.

63. The invention according to claim 28 wherein said faceted mirror elements are oriented with respect to said radiant energy emission means and said location region such that the radiant energy emitted by said radiant energy emission means is transmitted across said location region in substantially parallel beams spaced substantially evenly across said location region.

64. The invention according to claim 29 wherein said faceted mirror elements are oriented with respect to said location region and said radiant energy detection means such that said faceted mirror elements individually receive radiant energy from portions of said location region which are substantially parallel to one another and which are spaced substantially evenly across said location region.

65. The invention according to claim 15 wherein said collector means comprise stepped echelon mirror assemblies;
said stepped echelon mirror assemblies comprising a plurality of faceted mirror elements;
said faceted mirror elements oriented with respect to said location region and said scanner means such that said faceted mirror elements individually receive radiant energy from portions of said location region which are substantially parallel to one another and which are spaced substantially evenly across said location region;
each of said faceted mirror elements further being in optical alignment with said scanner means for substantially equal incremental angular portions of the rotation of said scanner means;
the separation between the centers of each of said faceted mirror elements corresponding to substantially equal incremental angular portions of the rotation of said rotating scanner means, whereby a substantially linear relationship exists between the instantaneous angular position of the rotating scanner means, and the transverse location of that select portion of said location region from which radiant energy is being instantaneously received by said radiant energy detection means via said stepped echelon mirror assembly.

66. The invention according to claim 28 or 29 wherein each of said faceted mirror elements receives a substantially equal portion of radiant energy from said radiant energy emission means.

67. The invention according to claim 28 or 29 wherein one or more of said faceted mirror elements include curved mirror surfaces for providing reflective focusing of the radiant energy.

68. The invention according to claim 15 wherein said scanner means comprises optical element means;
said optical element means being substantially symmetrical about an axis of rotation;
said optical element means comprising a first and a second element;
at least one of said first and second elements being substantially transparent to said radiant energy;
said first and second elements being divided by a substantially continuous surface, said surface being substantially diagonal to said axis of rotation, whereby radiation impinging said optical element means from directions disposed radially of said axis of rotation, passes through said transparent element and is refracted thereby, and whereby that portion of said impinging radiation which approaches from radial positions that are instantaneously within optical alignment with said surface is redirected by interaction at said surface to a direction substantially aligned with said axis of rotation, said redirected radiation thereafter passing further through and out of said transparent element, being thereby further refracted;
means for positioning said optical element means by rotating said optical element means about said axis of rotation to a multiplicity of radial alignments; and means coupling said positioning means to said optical element means.

69. The invention according to claim 68, wherein said positioning means comprises a motor, said motor serving to continuously rotate said optical element means, said optical element means being inherently balanced by said axial symmetry to minimize vibrations resulting from said rotation;
said scanner further including means for detecting properties of said redirected radiation;
said detecting means cooperating with said transparent element and located along said axis of rotation at said common location.

70. The invention according to claim 2 wherein said signal output means comprises:
detector buffer means, said detector buffer means responding to an electrical output signal of said radiant energy detection means and generating a corresponding buffer output signal;
output discriminator means, said output discriminator means connected to the output of said detector buffer means whereby said buffer output signal may be analyzed to determine whether said buffer output signal corresponds to the presence or absence of an object within that relevant portion of said location region which corresponds to that portion of said integrated collector means which is instantaneously in optical alignment with said scanner means and said radiant energy detection means;
said output discriminator means generating a first given output signal when said buffer output signal corresponds to the absence of an object within said relevant portion of said location region; and said output discriminator means generating a second given output substantially distinct from said first given output signal when said buffer output signal corresponds to the presence of an object within said relevant portion of said location region.

71. The invention according to claim 70 wherein said detector buffer means comprises:
amplifier means;
said amplifier means generating said buffer output signal, said buffer output signal thereby generated comprising a first variable voltage output signal;
said amplifier means including gain determining means;
said amplifier means further including electrical filter means for suppressing input signals of undesired extraneous frequencies;
said output discriminator means comprising d.c.
restorer means, said d.c. restorer means designed to add or subtract a given voltage to said first variable voltage output signal;
said output discriminator means further comprising Schmitt trigger means for outputting a first logic one level output when said d.c. variable voltage second output signal rises above a first predetermined voltage level, and outputting a second logic zero level output when said second variable output signal falls below a second predetermined voltage level.

72. An improved optical scanning apparatus for producing an optical scan along a given linear axis, said apparatus including:
electromagnetic radiation transducing means for emitting or detecting electromagnetic radiation;
means for restricting the effective field of view of said transducing means to a given beam of radiation;
means for rotatively scanning said beam throughout a rotational scan region, about a rotational axis;
stepped echelon mirror means;
said stepped echelon mirror means having a multiplicity of individual mirror facets;
said stepped echelon mirror means located within said scan region in alignment with said linear axis such that as said beam is rotatively scanned, the beam is first aligned with a first one of said faceted mirror elements at a first end of said stepped echelon mirror means, and is subsequently aligned with each remaining faceted mirror element as said beam continues to rotatively scan from said first end of said stepped echelon mirror means to the second end of said mirror means;
said faceted mirror elements being individually oriented to reflectively redirect said rotatively scanned beam to create location beams which traverse substantially parallel paths;
the centers of said parallel paths being substantially equally spaced along and relative to said linear axis;
said faceted mirror elements being located such that the angular displacement, measured relative to said rotational axis, between each successive adjacent facets is substantially equal, whereby a substantially linear relationship exists between the instantaneous angular position of the rotatively scanned beam relative to the rotational axis, and the transverse location of the resulting redirected location beam relative to the linear axis.

73. An optical position locating apparatus for locating the position of one or more objects along two or more coordinate axes of a defined area, as well as for determining other measurable parameters of said one or more objects such as the sizes thereof relative to said two or more coordinate axes, said apparatus comprising:
radiant energy emission means;
radiant energy detection means;
distribution means for distributing said radiant energy emitted by said radiant energy emission means over a location region from a position along a first portion of said region;
one or more integrated collector means positioned along a second portion of said location region and cooperating with said distributor means to receive said radiant energy distributed by said distributor means and to transmit said radiant energy to said radiant energy detection means, signal output means operably connected to said detection means; and means for selectively viewing portions of said distributed and received radiant energy to disclose properties of said radiant energy which have been altered as a result of said object being located within said location region so as to, in turn, determine the location of said object within said location region, as well as said other parameters of said object.

CLAIMS SUPPORTED BY THE SUPPLEMENTARY DISCLOSURE

74. The invention according to claim 21 wherein said amplifier responds to the intensity of current through said detector element;
said detector element comprising a photosensitive diode, said amplifier circuit further comprising gain means with noise suppressant means to transduce between the variable current of the photosensitive diode into a resulting voltage signal;
d.c. restorer means coupled to said gain means for restoring the d.c. level of signal; and analog output means producing an output signal whose magnitude is substantially related to the intensity of said radiant energy received by said radiant energy detector element.

75. The invention according to claim 1 wherein said optical position location apparatus is mounted in front of a visual display means whereby objects approaching within close proximity of the surface of said visual display means intrude within said location region of said optical position location apparatus and are detected.

76. The invention of claim 75 wherein the output of said optical position location apparatus is supplied to computing means such that the location of said object intruding within said location region, as well as other measurable parameters thereof, supply input data to said computing means.

77. the invention of claim 76 wherein said visual display means is connected to an output of said computing means, said output of said computing means being in part responsive to the input to said computing means supplied by said optical position location apparatus.

78. The invention according to claim 36 in which said apparatus further includes:
a fixed optical element;
said fixed optical element comprising a substantially hemispherical, transparent section;
said fixed optical element having a conical portion removed from the center thereof, the axis of said removed conical portion corresponding to the axis of said hemispherical section;
the resulting conical surface in said optical element being optically polished, whereby incident radiant energy entering said optical element from various radial positions is refracted and redirected by said optical element, exiting said optical element substantially along said aixs;
said radiant energy detection means being located along said axis of said optical element to receive said redirected radiant energy.

79. The invention according to claim 59 wherein said signal output means comprises analog output means;
said analog output means producing an output signal whose magnitude is substantially related to the intensity of said radiant energy received by said radiant energy detection means.

80. The invention according to claim 79 wherein said analog output means comprises linear amplifier means.