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Publication numberWO2000008415 A1
Publication typeApplication
Application numberPCT/IL1999/000431
Publication date17 Feb 2000
Filing date5 Aug 1999
Priority date5 Aug 1998
Also published asDE69920023D1, DE69920023T2, DE69928453D1, DE69928453T2, DE69928453T3, EP1102963A1, EP1102963B1, EP1327851A1, EP1327851B1, EP1327851B2, EP1645842A2, EP1645842A3, EP1645842B1, EP2439489A2, EP2439489A3, EP2439489B1, US6697164, US6940611, US7092107, US7230725, US7477402, US7630089, US7796277, US7944569, US7990548, US8310683, US8638447, US8638448, US9089277, US9615901, US20040090638, US20050264828, US20060158665, US20070109559, US20090148807, US20090153879, US20100165357, US20100165358, US20110279825, US20130094031, US20130177866, US20140104620, US20150282903, US20170196664
Publication numberPCT/1999/431, PCT/IL/1999/000431, PCT/IL/1999/00431, PCT/IL/99/000431, PCT/IL/99/00431, PCT/IL1999/000431, PCT/IL1999/00431, PCT/IL1999000431, PCT/IL199900431, PCT/IL99/000431, PCT/IL99/00431, PCT/IL99000431, PCT/IL9900431, WO 0008415 A1, WO 0008415A1, WO 2000/008415 A1, WO 2000008415 A1, WO 2000008415A1, WO-A1-0008415, WO-A1-2000008415, WO0008415 A1, WO0008415A1, WO2000/008415A1, WO2000008415 A1, WO2000008415A1
InventorsNoam Babayoff, Isaia Glaser-Inbari
ApplicantCadent Ltd.
Export CitationBiBTeX, EndNote, RefMan
External Links: Patentscope, Espacenet
Imaging a three-dimensional structure by confocal focussing an array of light beams
WO 2000008415 A1
Abstract
Determining surface topology of a portion (26) of a three-dimensional structure is provided. An array of incident light beams (36) passing through a focusing optics (42) and a probing face is shone on said portion. The focusing optics defines one or more focal planes forward the probing face in a position which can be changed (72) by the focusing optics. The beams generate illuminated spots (52) on the structure and the intensity of returning light rays propagating in an optical path opposite to that of the incident light rays is measured (60) at various positions of the focal plane(s). By determining spot-specific positions yielding a maximum intensity of the returned light beams, data is generated which is representative of said topology. Measurement of teeth. Light beams by grating of matrix of pinholes, micro lens array. Simultaneous imaging from three angles. Quicker with three different light components.
Claims  (OCR text may contain errors)
CLAIMS:
1. A method for determining surface topology of a portion of a three-dimensional structure, comprising:
(a) providing an array of incident light beams propagating in an optical path leading through a focusing optics and through a probing face; the focusing optics defining one or more focal planes forward said probing face in a position changeable by said optics, each light beam having its focus on one of said one or more focal plane; the beams generating a plurality of illuminated spots on the structure;
(b) detecting intensity of returned light beams propagating from each of these spots along an optical path opposite to that of the incident light;
(c) repeating steps (a) and (b) a plurality of times, each time changing position of the focal plane relative to the structure;
(d) for each of the illuminated spots, determining a spot-specific position, being the position of the respective focal plane yielding a maximum measured intensity of a respective returned light beam; and (e) generating data representative of the topology of said portion.
2. The method according to Claim 1, wherein the plurality of incident light beams are produced by splitting a single parent beam.
3. The method according to Claim 1, wherein step (a) comprises polarizing the incident light beams.
4. The method according to Claim 3, wherein step (b) comprises filtering light having polarization same as the incident light and measuring light of opposite polarization.
5. The method according to any one of Claims 1-4, wherein each of said beams is composed of at least two light components different in at least one parameter.
6. The method according to Claim 5, wherein said at least one parameter is selected from the group consisting of wavelength, phase, light pulse duration and pattern.
7. The method according to Claim 5, comprising, in step (b), determining intensity independently for each of said at least two light components in the return light beams.
8. The method according to Claim 7, wherein each of said at least two light components focuses in a plane differently distanced from the sensing surface.
9. The method according to any one of Claims 1-8, wherein the data representative of said topology is used for constructing an object to be fitted within said structure.
10. The method according to any one of Claims 1-9, wherein the data representative of said topology is converted into a form transmissible through a communication medium to recipient.
11. The method according to any one of the preceding claims, wherein said structure is a teeth segment.
12. The method according to Claim 12, wherein said structure is a teeth segment with at least one missing tooth or a portion of a tooth and said object is said at least one missing tooth or the portion of the tooth.
13. A method for reconstruction of topology of a three-dimensional structure comprising:
(i) determining surface topologies from at least two different positions or angular locations relative to the structure, by the method defined in any one of Claims 1-12; (ii) combining the surface topologies to obtain data representative of said structure.
14. The method according to Claim 13, for reconstruction of topology of a teeth portion, comprising: - determining surface topologies of at least a buccal surface and a lingual surface of the teeth portion;
- combining the surface topologies to obtain data representative of a three-dimensional structure of said teeth portion.
15. The method according to Claim 14, for obtaining data representative of a three-dimensional structure of a teeth portion with at least one missing tooth or a portion of a tooth.
16. The method according to Claim 15, wherein said data is used in a process of designing or manufacturing of a prostheses of said at least one missing tooth or a portion of a tooth.
17. The method according to Claim 16, wherein said prostheses is a crown or a bridge.
18. An apparatus for determining surface topology of a portion of a three-dimensional structure, comprising:
- a probing member with a sensing face; - an illumination unit for providing an array of incident light beams transmitted towards the structure along an optical path through said probing unit to generate illuminated spots on said portion ;
- a light focusing optics defining one or more focal planes forward said probing face at a position changeable by said optics, each light beam having its focus on one of said one or more focal plane;
- a translation mechanism for displacing said focal plane relative to the structure along an axis defined by the propagation of the incident light beams: - a detector having an array of sensing elements for measuring intensity of each of a plurality of light beamsreturning from said spots propagating through an optical path opposite to that of the incident light beams;
- a processor coupled to said detector for determining for each light beam a spot-specific position, being the position of the respective focal plane of said one or more focal planes yielding maximum measured intensity of the returned light beam, and based on the determined spot-specific positions, generating data representative of the topology of portion.
19. The apparatus according to Claim 18, wherein said illumination unit comprises a source emitting a parent light beam and a beam splitter for splitting the parent beam into said array of incident light beams.
20. The apparatus according to Claim 19, wherein said illumination unit comprises a grating or microlens array.
21. The apparatus according to any one of Claims 18-20, comprising a polarizer for polarizing said incident light beams are polarized.
22. The apparatus according to Claim 21, comprising a polarization filter for filtering out from the returned light beams light components having the polarization of the incident light beams.
23. The apparatus according to any one of Claim 18-22, wherein the illumination unit comprises at least two light sources and each of said incident beams is composed of light components from the at least two light sources.
24. The apparatus according to Claim 23, wherein the at least two light sources emit each a light component of different wavelength.
25. The apparatus according to Claim 24, wherein said light directing optics defines a different focal plane for each light component and the detector independently detects intensity of each light components.
26. The apparatus according to Claim 23, wherein the at least two light sources are located so as to define optical paths of different lengths for the incident light beams emitted by each of the at least two light sources.
27. The apparatus according to any one of Claims 18-26, wherein said focusing optics operates in a telecentric confocal mode.
28. The apparatus according to any one of Claims 18-27, wherein said light directing optics comprises optical fibers.
29. The apparatus according to any one of Claims 18-28, wherein said sensing elements are an array of charge coupled devices (CCD).
30. The apparatus according to Claim 29, wherein, said detector unit comprises a pinhole array, each pinhole corresponding to one of the CCDs in the CCD array.
31. The apparatus according to any one of Claims 18-30, comprising a unit for generating data for transmission to CAD/CAM device.
32. The apparatus according to Claim 31, comprising a communication port of a communication medium.
33. The apparatus according to any one of Claims 18-32, for determining surface topology of a teeth portion, comprising an optical probing memeber for placing proximal to the teeth.
Description  (OCR text may contain errors)

IMAGING A THREE-DIMENSIONAL STRUCTURE BY CONFOCAL FOCUSSING AN

ARRAY OF LIGHT BEAMS

FIELD OF THE INVENTION

This invention in the field of imaging techniques and relates to a method and an apparatus for non-contact imaging of three-dimensional structures, particularly useful for direct surveying of teeth.

BACKGROUND OF THE INVENTION

A great variety of methods and systems have been developed for direct optical measurement of teeth and the subsequent automatic manufacture of dentures. The term "direct optical measurement" signifies surveying of teeth in the oral cavity of a patient. This facilitates the obtainment of digital constructional data necessary for the computer-assisted design (CAD) or computer-assisted manufacture (CAM) of tooth replacements without having to make any cast impressions of the teeth. Such systems typically includes an optical probe coupled to an optical pick-up or receiver such as charge coupled device (CCD) and a processor implementing a suitable image processing technique to design and fabricate virtually the desired product.

One conventional technique of the kind specified is based on a laser-triangulation method for measurement of the distance between the surface of the tooth and the optical distance probe, which is inserted into the oral cavity of the patient. The main drawback of this technique consists of the following. It is assumed that the surface of the tooth reflects optimally, e.g.

Lambert's reflection. Unfortunately, this is not the case in practice and often the data that is obtained is not accurate. Other techniques, which are embodied in CEREC-1 and CEREC-2 systems commercially available from Siemens GmbH or Sirona Dental

Systems, utilize the light-section method and phase-shift method, respectively.

Both systems employ a specially designed hand-held probe to measure the three-dimensional coordinates of a prepared tooth. However, the methods require a specific coating (i.e. measurement powder and white-pigments suspension, respectively) to be deposited to the tooth. The thickness of the coating layer should meet specific, difficult to control requirements, which leads to inaccuracies in the measurement data.

By yet another technique, mapping of teeth surface is based on physical scanning of the surface by a probe and by determining the probe's position, e.g. by optical or other remote sensing means, the surface may be imaged.

U.S. Patent No. 5,372,502 discloses an optical probe for three-dimensional surveying. The operation of the probe is based on the following. Various patterns are projected onto the tooth or teeth to be measured and corresponding plurality of distorted patterns are captured by the probe. Each interaction provides refinement of the topography.

SUMMARY OF THE INVENTION

The present invention is directed to a method and apparatus for imaging three-dimensional structures. A preferred, non-limiting embodiment, is concerned with the imaging of a three-dimensional topology of a teeth segment, particularly such where one or more teeth are missing. This may allow the generation of data for subsequent use in design and manufacture of, for example, prosthesis of one or more teeth for incorporation into said teeth segment. Particular examples are the manufacture of crowns or bridges.

The present invention provides, by a first of its aspects, a method for determining surface topology of a portion of a three-dimensional structure, comprising:

(a) providing an array of incident light beams propagating in an optical path leading through a focusing optics and a probing face; the focusing optics defining one or more focal planes forward said probing face in a position changeable by said optics, each light beam having its focus on one of said one or more focal plane; the beams generating a plurality of illuminated spots on the structure;

(b) detecting intensity of returned light beams propagating from each of these spots along an optical path opposite to that of the incident light; (c) repeating steps (a) and (b) a plurality of times, each time changing position of the focal plane relative to the structure; and

(d) for each of the illuminated spots, determining a spot-specific position, being the position of the respective focal plane, yielding a maximum measured intensity of a respective returned light beam; and

(e) based on the determined spot-specific positions, generating data representative of the topology of said portion. By a further of its aspects, the present invention provides an apparatus for determining surface topology of a portion of a three-dimensional structure, comprising:

- a probing member with a sensing face;

- an illumination unit for providing an array of incident light beams transmitted towards the structure along an optical path through said probing unit to generate illuminated spots on said portion; - a light focusing optics defining one or more focal planes forward said probing face at a position changeable by said optics, each light beam having its focus on one of said one or more focal plane ;

- a translation mechanism coupled to said focusing optics for displacing said focal plane relative to the structure along an axis defined by the propagation of the incident light beams;

- a detector having an array of sensing elements for measuring intensity of each of a plurality of light beams returning from said spots propagating through an optical path opposite to that of the incident light beams; - a processor coupled to said detector for determining for each light beam a spot-specific position, being the position of the respective focal plane of said one or more focal planes yielding maximum measured intensity of the returned light beam, and based on the determined spot-specific positions, generating data representative of the topology of said portion. The probing member, the illumination unit and the focusing optics and the translation mechanism are preferably included together in one device, typically a hand-held device. The device preferably includes also the detector. The determination of the spot-specific positions in fact amounts to determination of the in-focus distance. The determination of the spot-specific position may be by measuring the intensity per se, or typically is performed by measuring the displacement (S) derivative of the intensity (I) curve (dl/dS) and determining the relative position in which this derivative function indicates a maximum maximum intensity. The term "spot-specific position (SSP) " will be used to denote the relative in-focus position regardless of the manner in which it is determined. It should be understood that the SSP is always a relative position as the absolute position depends on the position of the sensing face. However the generation of the surface topology does not require knowledge of the absolute position, as all dimensions in the cubic field of view are absolute. The SSP for each illuminated spot will be different for different spots. The position of each spot in an X-Y frame of reference is known and by knowing the relative positions of the focal plane needed in order to obtain maximum intensity (namely by determining the SSP) , the Z or depth coordinate can be associated with each spot and thus by knowing the X-Y-Z coordinates of each spot the surface topology can be generated.

In accordance with one embodiment, in order to determine the Z coordinate (namely the SSP) of each illuminated spot the position of the focal plane is scanned over the entire range of depth or Z component possible for the measured surface portion. In accordance with another embodiment the beams have components which each has a different focal plane. Thus, in accordance with this latter embodiment by independent determination of SSP for the different light components, e.g. 2 or 3 with respective corresponding 2 or 3 focal planes, the position of the focal planes may be changed by the focusing optics to scan only part of the possible depth range, with all focal planes together covering the expected depth range. In accordance with yet another embodiment, the determination of the SSP involves a focal plane scan of only part of the potential depth range and for illuminated spots where a maximum illuminated intensity was not reached, the SSP is determined by extrapolation from the measured values or other mathematical signal processing methods.

The method and apparatus of the invention are suitable for determining a surface topology of a wide variety of three-dimensional structures. A preferred implementation of method and apparatus of the invention are in determining surface topology of a teeth section.

In accordance with one embodiment of the invention, the method and apparatus are used to construct an object to be fitted within said structure. In accordance with the above preferred embodiment, such an object is at least one tooth or a portion of a tooth missing in the teeth section. Specific examples include a crown to be fitted on a tooth stump or a bridge to be fitted within teeth.

By one embodiment of the invention, the plurality of incident light beams are produced by splitting a parent beam. Alternatively, each incident light beam or a group of incident light beams may be emitted by a different light emitter. In accordance with a preferred embodiment, light emitted from a light emitter passes through a diffraction or refraction optics to obtain the array of light beams.

In accordance with one embodiment, the parent light beam is light emitted from a single light emitter. In accordance with another embodiment, the parent light beam is composed of different light components, generated by different light emitters, the different light components differing from one another by at least one detectable parameter. Such a detectable parameter may, for example be wavelength, phase, different duration or pulse pattern, etc. Typically, each of said light components has its focus in a plane differently distanced from the structure than other light components. In such a case, when the focal plane of the optics is changed, simultaneously the different ranges of depth (or Z component) will be scanned. Thus, in such a case, for each illuminated spot there will be at least one light component which will yield a maximum intensity, and the focal distance associated with this light component will then define the Z component of the specific spot.

In accordance with an embodiment of the invention the incident light beams are polarized. In accordance with this embodiment, typically the apparatus comprises a polarization filter for filtering out, from the returned light beams, light components having the polarization of the incident light, whereby light which is detected is that which has an opposite polarization to that of the incident light.

The data representative of said topology may be used for virtual reconstruction of said surface topology, namely for reconstruction within the computer environment. The reconstructed topology may be represented on a screen, may be printed, etc., as generally known per se. Furthermore, the data representative of said topology may also be used for visual or physical construction of an object to be fitted within said structure. In the case of the preferred embodiment noted above, where said structure is a teeth section with at least one missing tooth or tooth portion, said object is a prosthesis of one or more tooth, e.g. a crown or a bridge.

By determining surface topologies of adjacent portions, at times from two or more different angular locations relative to the structure, and then combining such surface topologies, e.g in a manner known per se, a complete three-dimensional representation of the entire structure may be obtained. Data representative of such a representation may, for example, be used for virtual or physical reconstruction of the structure, may be transmitted to another apparatus or system for such reconstruction, e.g. to a CAD/CAM apparatus. Typically, but not exclusively, the apparatus of the invention comprises a communication port for connection to a communication network which may be a computer network, a telephone network, a wireless communication network, etc.

BRIEF DESCRIPTION OF THE DRAWINGS In order to understand the invention and to see how it may be carried out in practice, a preferred embodiment will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which:

Figs. 1A and IB are a schematic illustration by way of a block diagram of an apparatus in accordance with an embodiment of the invention (Fig. IB is a continuation of Fig. 1A);

Fig. 2A is a top view of a probing member in accordance with an embodiment of the invention; Fig. 2B is a longitudinal cross-section through line II-II in Fig. 2A, depicting also some exemplary rays passing therethrough;

Fig. 3 is a schematic illustration of another embodiment of a probing member ; and Fig. 4 is a schematic illustration of an embodiment where the parent light beam, and thus each of the incident light beams, is composed of several light components, each originating from a different light emitter.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT Reference is first being made to Figs. 1A and IB illustrating, by way of a block diagram an apparatus generally designated 20, consisting of an optical device 22 coupled to a processor 24. The embodiment illustrated in Fig. 1 is particularly useful for determining the three-dimensional structure of a teeth segment 26, particularly a teeth segment where at least one tooth or portion of tooth is missing for the purpose of generating data of such a segment for subsequent use in design or manufacture of a prosthesis of the missing at least one tooth or portion, e.g. a crown or a bridge. It should however be noted, that the invention is not limited to this embodiment, and applies, mutatis mutandis, also to a variety of other applications of imaging of three-dimensional structure of objects, e.g. for the recordal or archeological objects, for imaging of a three-dimensional structure of any of a variety of biological tissues, etc.

Optical device 22 comprises, in this specific embodiment, a semiconductor laser unit 28 emitting a laser light, as represented by arrow 30. The light passes through a polarizer 32 which gives rise to a certain polarization of the light passing through polarizer 32. The light then enters into an optic expander 34 which improves the numerical aperture of the light beam 30. The light beam 30 then passes through a module 38, which may, for example, be a grating or a micro lens array which splits the parent beam 30 into a plurality of incident light beams 36, represented here, for ease of illustration, by a single line. The operation principles of module 38 are known per se and the art and these principles will thus not be elaborated herein.

The light unit 22 further comprises a partially transparent mirror 40 having a small central aperture. It allows transfer of light from the laser source through the downstream optics, but reflects light travelling in the opposite direction. It should be noted that in principle, rather than a partially transparent mirror other optical components with a similar function may also be used, e.g. a beam splitter. The aperture in the mirror 40 improves the measurement accuracy of the apparatus. As a result of this mirror structure the light beams will yield a light annulus on the illuminated area of the imaged object as long as the area is not in focus; and the annulus will turn into a completely illuminated spot once in focus. This will ensure that a difference between the measured intensity when out-of- and in-focus will be larger. Another advantage of a mirror of this kind, as opposed to a beam splitter, is that in the case of the mirror internal reflections which occur in a beam splitter are avoided, and hence the signal-to-noise ratio improves.

The unit further comprises a confocal optics 42, typically operating in a telecentric mode, a relay optics 44, and an endoscopic probing member 46. Elements 42, 44 and 46 are generally as known per se. It should however be noted that telecentric confocal optics avoids distance-introduced magnification changes and maintains the same magnification of the image over a wide range of distances in the Z direction (the Z direction being the direction of beam propagation). The relay optics enables to maintain a certain numerical aperture of the beam's propagation.

The endoscopic probing member typically comprises a rigid, light-transmitting medium, which may be a hollow object defining within it a light transmission path or an object made of a light transmitting material, e.g. a glass body or tube. At its end, the endoscopic probe typically comprises a mirror of the kind ensuring a total internal reflection and which thus directs the incident light beams towards the teeth segment 26. The endoscope 46 thus emits a plurality of incident light beams 48 impinging on to the surface of the teeth section. Incident light beams 48 form an array of light beams arranged in an

X-Y plane, in the Cartasian frame 50, propagating along the Z axis. As the surface on which the incident light beams hits is an uneven surface, the illuminated spots 52 are displaced from one another along the Z axis, at different (X;,Yj) locations. Thus, while a spot at one location may be in focus of the optical element 42, spots at other locations may be out-of-focus. Therefore, the light intensity of the returned light beams (see below) of the focused spots will be at its peak, while the light intensity at other spots will be off peak. Thus, for each illuminated spot, a plurality of measurements of light intensity are made at different positions along the Z-axis and for each of such (X;, Yj) location, typically the derivative of the intensity over distance (Z) will be made, the Z; yielding maximum derivative, Z0, will be the in-focus distance. As pointed out above, where, as a result of use of the punctured mirror 40, the incident light forms a light disk on the surface when out of focus and a complete light spot only when in focus, the distance derivative will be larger when approaching in-focus position thus increasing accuracy of the measurement.

The light scattered from each of the light spots includes a beam travelling initially in the Z axis along the opposite direction of the optical path traveled by the incident light beams. Each returned light beam 54 corresponds to one of the incident light beams 36. Given the unsymmetrical properties of mirror 40, the returned light beams are reflected in the direction of the detection optics generally designated 60. The detection optics comprises a polarizer 62 that has a plane of preferred polarization oriented normal to the plane polarization of polarizer 32. The returned polarized light beam 54 pass through an imaging optic 64, typically a lens or a plurality of lenses, and then through a matrix 66 comprising an array of pinholes. CCD camera has a matrix or sensing elements each representing a pixel of the image and each one corresponding to one pinhole in the array 66.

The CCD camera is connected to the image-capturing module 80 of processor unit 24. Thus, each light intensity measured in each of the sensing elements of the CCD camera, is then grabbed and analyzed, in a manner to be described below, by processor 24. Unit 22 further comprises a control module 70 connected to a controlling operation of both semi-conducting laser 28 and a motor 72. Motor 72 is linked to telecentric confocal optics 42 for changing the relative location of the focal plane of the optics 42 along the Z-axis. In a single sequence of operation, control unit 70 induces motor 72 to displace the optical element 42 to change the focal plane location and then, after receipt of a feedback that the location has changed, control module 70 will induce laser 28 to generate a light pulse. At the same time it will synchronize image-capturing module 80 to grab data representative of the light intensity from each of the sensing elements. Then in subsequent sequences the focal plane will change in the same manner and the data capturing will continue over a wide focal range of optics 44, 44.

Image capturing module 80 is connected to a CPU 82 which then determines the relative intensity in each pixel over the entire range of focal planes of optics 42, 44. As explained above, once a certain light spot is in focus, the measured intensity will be maximal. Thus, by determining the Z; corresponding to the maximal light intensity or by determining the maximum displacement derivative of the light intensity, for each pixel, , the relative position of each light spot along the Z axis can be determined. Thus, data representative of the three-dimensional pattern of a surface in the teeth segment, can be obtained. This three-dimensional representation may be displayed on a display 84 and manipulated for viewing, e.g. viewing from different angles, zooming-in or out, by the user control module 86 (typically a computer keyboard). In addition, the data representative of the surface topology may be transmitted through an appropriate data port, e.g. a modem 88, through any communication network, e.g. telephone line 90, to a recipient (not shown) e.g. to an off-site CAD/CAM apparatus (not shown).

By capturing, in this manner, an image from two or more angular locations around the structure, e.g. in the case of a teeth segment from the buccal direction, from the lingal direction and optionally from above the teeth, an accurate three-dimensional representation of the teeth segment may be reconstructed. This may allow a virtual reconstruction of the three- dimensional structure in a computerized environment or a physical reconstruction in a CAD/CAM apparatus.

As already pointed out above, a particular and preferred application is imaging of a segment of teeth having at least one missing tooth or a portion of a tooth, and the image can then be used for the design and subsequent manufacture of a crown or any other prosthesis to be fitted into this segment.

Reference is now being made to Figs. 2A AND 2B illustrating a probing member 90 in accordance with one, currently preferred, embodiment of the invention. The probing member 90 is made of a light transmissive material, typically glass and is composed of an anterior segment 91 and a posterior segment 92, tightly glued together in an optically transmissive manner at 93. Slanted face 94 is covered by a totally reflective mirror layer 95. Glass disk 96 defining a sensing surface 97 is disposed at the bottom in a manner leaving an air gap 98. The disk is fixed in position by a holding structure which is not shown. Three light rays are 99 are represented schematically. As can be seen, they bounce at the walls of the probing member at an angle in which the walls are totally reflective and finally bounce on mirror 94 and reflected from there out through the sensing face 97. The light rays focus on focusing plane 100, the position of which can be changed by the focusing optics (not shown in this figure).

Reference is now being made to Fig. 3, which is a schematic illustration of an endoscopic probe in accordance with an embodiment of the invention. The endoscopic probe, generally designated 101, has a stem 102 defining a light transmission path (e.g., containing a void elongated space, being made of or having an interior made of a light transmitting material. Probe 102 has a trough-like probe end 104 with two lateral probe members 106 and 108 and a top probe member 110. The optical fibers have light emitting ends in members 106, 108 and 110 whereby the light is emitted in a direction normal to the planes defined by these members towards the interior of the trough- like structure 104. The probe is placed over a teeth segment 120, which in the illustrated case consists of two teeth 122 and 124, and a stamp 126 of a tooth for placement of a crown thereon. Such a probe will allow the simultaneous imaging of the surface topology of the teeth segment from three angles and subsequently the generation of a three-dimensional structure of this segment.

Reference is now being made to Fig. 4. In this figure, a number of components of an apparatus generally designated 150 in accordance with another embodiment are shown. Other components, not shown, may be similar to those of the embodiment shown in Fig. 1. In this apparatus a parent light beam 152 is a combination of light emitted by a number of laser light emitters 154A, 154B and 154C. Optic expander unit 156 then expands the single parent beam into an array of incident light beams 158. Incident light beams pass through unidirectional mirror 160, then through optic unit 162 towards object 164.

The different light components composing parent beam 152 may for example be different wavelengths, a different one transmitted from each of laser emitters 154A-C. Thus, parent light beam 152 and each of incident light beams 158 will be composed of three different light components. The image of the optics, or an optical arrangement associated with each of light emitters may be arranged such that each light component focuses on a different plane, PA, PB and Pc, respectively. Thus in the position shown in Fig. 3, incident light beam 158A bounces on the surface at spot 170A which in the specific optical arrangement of optics 162 is in the focal point for light component A (emitted by light emitter 154A). Thus, the returned light beam 172A, passing through detection optics 174 yield maximum measured intensity of light component A measured by two-dimensional array of spectrophotometers 176, e.g. a 3 CHIP CCD camera. Similarly, different maximal intensity will be reached for spots 170B and 170C for light components B and C, respectively.

Thus, by using different light components each one focused simultaneously at a different plane, the time measurement can be reduced as different focal plane ranges can simultaneously be measured.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
WO1997037264A1 *28 Mar 19979 Oct 1997Komatsu Ltd.Confocal optical apparatus
DE19638758A1 *13 Sep 199619 Mar 1998Rubbert RuedgerVerfahren und Vorrichtung zur dreidimensionalen Vermessung von Objekten
DE19640495A1 *1 Oct 19969 Apr 1998Leica LasertechnikVorrichtung zur konfokalen Oberflächenvermessung
DE19650391A1 *5 Dec 199610 Jun 1998Leica LasertechnikAnordnung und Verfahren zur simultanen polyfokalen Abbildung des Oberflächenprofils beliebiger Objekte
EP0679864A1 *30 Sep 19942 Nov 1995Kabushiki Kaisha Komatsu SeisakushoConfocal optical apparatus
GB2144537A * Title not available
GB2321517A * Title not available
US4575805 *23 Aug 198411 Mar 1986Moermann Werner HMethod and apparatus for the fabrication of custom-shaped implants
US5381236 *6 Feb 199210 Jan 1995Oxford Sensor Technology LimitedOptical sensor for imaging an object
US5737084 *26 Sep 19967 Apr 1998Takaoka Electric Mtg. Co., Ltd.Three-dimensional shape measuring apparatus
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
WO2004008981A222 Jul 200329 Jan 2004Cadent Ltd.A method for defining a finish line of a dental prosthesis
WO2006061347A1 *1 Dec 200515 Jun 2006Sirona Dental Systems GmbhMeasuring device and method that operates according to the basic principles of confocal microscopy
WO2008092791A1 *24 Jan 20087 Aug 2008Sirona Dental Systems GmbhApparatus and method for optical 3d measurement
WO2010145669A117 Jun 201023 Dec 20103Shape A/SFocus scanning apparatus
WO2012011101A219 Jul 201126 Jan 2012Cadent Ltd.Methods and systems for creating and interacting with three dimensional virtual models
WO2014095134A1 *24 Oct 201326 Jun 2014Ivoclar Vivadent AgMethod for producing a dental restoration part, and dental furnace
WO2014096931A117 Dec 201326 Jun 2014Align Technology, Inc.Methods and systems for dental procedures
WO2015015289A230 Jul 20145 Feb 2015Align Technology, Inc.Methods and systems for generating color images
WO2015075215A124 Nov 201428 May 2015Sirona Dental Systems GmbhOptical measuring system and method for optically measuring an object in a three-dimensional manner
WO2016001835A1 *30 Jun 20157 Jan 2016Align Technology, Inc.Confocal surface topography measurement with a focal plane inclined with respect to the direction of the relative movement of confocal apparatus and sample
WO2016005856A11 Jul 201514 Jan 2016Align Technology, Inc.Apparatus for dental confocal imaging
WO2016009294A11 Jul 201521 Jan 2016Align Technology, Inc.Probe head and apparatus for intraoral confocal imaging
WO2016024158A3 *17 Aug 201514 Apr 2016Align Technology, Inc.Confocal imaging apparatus with curved focal surface or target reference element and field compensator
WO2016030741A1 *24 Aug 20153 Mar 2016Align Technology, Inc.Illumination means with uniform energy profile and vcsel based low coherence emitter for confocal 3d scanner
CN104883996A *24 Oct 20132 Sep 2015伊沃克拉尔维瓦登特股份公司Method for producing a dental restoration part, and dental furnace
CN104883996B *24 Oct 20138 Aug 2017伊沃克拉尔维瓦登特股份公司制造牙齿修复件的方法以及牙科用炉
DE102004059526B4 *9 Dec 20048 Mar 2012Sirona Dental Systems GmbhVermessungseinrichtung und Verfahren nach dem Grundprinzip der konfokalen Mikroskopie
DE102008044522A112 Sep 200818 Mar 2010Degudent GmbhVerfahren und Vorrichtung zur Erfassung von Konturdaten und/oder optischen Eigenschaften eines dreidimensionalen semitransparenten Objekts
DE102013223894B3 *22 Nov 201319 Feb 2015Sirona Dental Systems GmbhOptisches Messsystem und Verfahren zur dreidimensionalen optischen Vermessung eines Objekts
EP1561433A12 Feb 200510 Aug 2005Cadent LimitedMethod and system for manufacturing a dental prosthesis
EP1607064A217 Jun 200521 Dec 2005Cadent Ltd.Method and apparatus for colour imaging a three-dimensional structure
EP1607064A3 *17 Jun 200511 Jan 2006Cadent Ltd.Method and apparatus for colour imaging a three-dimensional structure
EP1662414A228 Nov 200531 May 2006Cadent Ltd.Method and system for providing feedback data useful in prosthodontic procedures associated with the intra oral cavity
EP1742017A2 *9 Jun 200610 Jan 2007Rolls-Royce plcA monitoring arrangement
EP1742017A3 *9 Jun 200617 Jan 2007Rolls-Royce plcA monitoring arrangement
EP1941843A3 *17 Jun 200523 Jul 2008Cadent Ltd.Method and apparatus for colour imaging a three-dimensional structure
EP2335640A121 Dec 200922 Jun 2011Cadent Ltd.Jig for use with dental analogs and models
EP2465464A22 Oct 200320 Jun 2012Cadent Ltd.A method for preparing a physical plaster model
EP2586368A3 *26 Oct 201216 Oct 2013Covidien LPCollimated beam metrology systems for in-situ surgical applications
EP2745801A1 *18 Dec 201225 Jun 2014Ivoclar Vivadent AGMethod for producing a dental restoration part, and dental oven
EP3058892A121 Dec 200924 Aug 2016Align Technology, Inc.Jig for use with dental analogs and models
EP3130311A124 Feb 200515 Feb 2017Align Technology, Inc.Method and system for designing and producing dental prostheses and appliances
US6957118 *1 Apr 200418 Oct 2005Cadent Ltd.Method and system for fabricating a dental coping, and a coping fabricated thereby
US7110844 *31 Aug 200519 Sep 2006Cadent Ltd.Method and system for fabricating a dental prosthesis, and a prosthesis wax model
US711206522 Jul 200326 Sep 2006Cadent Ltd.Method for defining a finish line of a dental prosthesis
US72368421 Dec 200526 Jun 2007Cadent Ltd.System and method for manufacturing a dental prosthesis and a dental prosthesis manufactured thereby
US725555818 Jun 200214 Aug 2007Cadent, Ltd.Dental imaging instrument having air stream auxiliary
US72869542 Mar 200623 Oct 2007Cadent Ltd.System and method for scanning an intraoral cavity
US731952917 Jun 200515 Jan 2008Cadent LtdMethod and apparatus for colour imaging a three-dimensional structure
US733387423 Feb 200519 Feb 2008Cadent Ltd.Method and system for designing and producing dental prostheses and appliances
US73830944 Aug 20063 Jun 2008Cadent Ltd.Method for CNC milling a wax model of a dental prosthesis or coping
US748817416 Aug 200610 Feb 2009Cadent Ltd.Method for defining a finish line of a dental prosthesis
US750212812 Jun 200610 Mar 2009Rolls Royce, PlcMonitoring arrangement for rotating components
US75118299 Aug 200731 Mar 2009Cadent Ltd.Method and apparatus for colour imaging a three-dimensional structure
US75554038 Feb 200630 Jun 2009Cadent Ltd.Method for manipulating a dental virtual model, method for creating physical entities based on a dental virtual model thus manipulated, and dental models thus created
US76893106 Apr 200730 Mar 2010Cadent Ltd.System and method for manufacturing a dental prosthesis and a dental prosthesis manufactured thereby
US769806817 Jun 200513 Apr 2010Cadent Ltd.Method for providing data associated with the intraoral cavity
US772437819 Feb 200925 May 2010Cadent Ltd.Method and apparatus for colour imaging a three-dimensional structure
US77343686 Aug 20088 Jun 2010Cadent Ltd.Method for manipulating a dental virtual model, method for creating physical entities based on a dental virtual model thus manipulated, and dental models thus created
US77389894 Jan 200815 Jun 2010Cadent Ltd.Method and system for designing and producing dental prostheses and appliances
US78135913 Sep 200612 Oct 20103M Innovative Properties CompanyVisual feedback of 3D scan parameters
US78388169 Mar 200723 Nov 2010Cadent, Ltd.Speckle reduction method and apparatus
US78400423 Sep 200623 Nov 20103M Innovative Properties CompanySuperposition for visualization of three-dimensional data acquisition
US786233625 Nov 20054 Jan 2011Cadent Ltd.Method and system for providing feedback data useful in prosthodontic procedures associated with the intra oral cavity
US78902908 Aug 200715 Feb 2011Cadent Ltd.System and method for scanning an intraoral cavity
US79122573 Sep 200622 Mar 20113M Innovative Properties CompanyReal time display of acquired 3D dental data
US794026016 May 200610 May 20113M Innovative Properties CompanyThree-dimensional scan recovery
US79426715 Dec 200617 May 2011Cadent Ltd.Method for preparing a physical plaster model
US79468467 Feb 200724 May 2011Cadent Ltd.Dental imaging instrument having air stream auxiliary
US798641521 Jul 200926 Jul 2011Sirona Dental Systems GmbhApparatus and method for optical 3D measurement
US799609925 Apr 20089 Aug 2011Cadent Ltd.Method and system for fabricating a dental coping, and a coping fabricated thereby
US803563720 Jan 200611 Oct 20113M Innovative Properties CompanyThree-dimensional scan recovery
US804143931 Dec 200918 Oct 2011Cadent Ltd.Method for manipulating a dental virtual model, method for creating physical entities based on a dental virtual model thus manipulated, and dental models thus created
US810253829 Apr 201024 Jan 2012Cadent Ltd.Method and apparatus for colour imaging a three-dimensional structure
US814534028 May 201027 Mar 2012Cadent Ltd.Method and system for designing and producing dental prostheses and appliances
US83591157 Sep 201122 Jan 2013Cadent Ltd.Method for manipulating a dental virtual model, method for creating physical entities based on a dental virtual model thus manipulated, and dental models thus created
US836322821 Dec 201129 Jan 2013Cadent Ltd.Method and apparatus for colour imaging a three-dimensional structure
US84543647 Mar 20074 Jun 2013Cadent Ltd.Method for preparing a physical plaster model
US847658120 Oct 20102 Jul 2013Cadent Ltd.Speckle reduction method and apparatus
US850993216 Jul 200913 Aug 2013Cadent Ltd.Methods, systems and accessories useful for procedures relating to dental implants
US85705303 Jun 200929 Oct 2013Carestream Health, Inc.Apparatus for dental surface shape and shade imaging
US857749317 Feb 20125 Nov 2013Align Technology, Inc.Method and system for designing and producing dental prostheses and appliances
US869057422 Mar 20118 Apr 2014Biomet 3I, LlcMethods for placing an implant analog in a physical model of the patient's mouth
US878036217 Apr 201215 Jul 2014Covidien LpMethods utilizing triangulation in metrology systems for in-situ surgical applications
US880556314 Dec 201212 Aug 2014Cadent Ltd.Method for manipulating a dental virtual model, method for creating physical entities based on a dental virtual model thus manipulated, and dental models thus created
US88453302 May 201330 Sep 2014Cadent, Ltd.Method for preparing a physical plaster model
US88558004 Apr 20127 Oct 2014Biomet 3I, LlcMethod for manufacturing dental implant components
US885823126 Nov 201014 Oct 2014Cadent Ltd.Method and system for providing feedback data useful in prosthodontic procedures associated with the intra oral cavity
US887057417 Oct 201328 Oct 2014Biomet 3I, LlcMethod of creating an accurate bone and soft-tissue digital dental model
US887890517 Jun 20104 Nov 20143Shape A/SFocus scanning apparatus
US88825086 Dec 201111 Nov 2014Biomet 3I, LlcUniversal scanning member for use on dental implant and dental implant analogs
US88884886 Mar 201318 Nov 2014Biomet 3I, LlcMethod for pre-operative visualization of instrumentation used with a surgical guide for dental implant placement
US89093638 Mar 20109 Dec 2014Align Technology, Inc.System and method for manufacturing a dental prosthesis and a dental prosthesis manufactured thereby
US892632827 Dec 20126 Jan 2015Biomet 3I, LlcJigs for placing dental implant analogs in models and methods of doing the same
US8934095 *8 Jan 201313 Jan 2015Vita Zahnfabrik H. Rauter Gmbh & Co. KgMiniaturized system and method for measuring optical characteristics
US893646422 Feb 201020 Jan 2015Cadent Ltd.Method, system and model for indirect bonding
US894481616 May 20123 Feb 2015Biomet 3I, LlcTemporary abutment with combination of scanning features and provisionalization features
US894481816 May 20123 Feb 2015Biomet 3I, LlcTemporary abutment with combination of scanning features and provisionalization features
US896799915 Jun 20113 Mar 2015Biomet 3I, LlcComponents for use with a surgical guide for dental implant placement
US899861420 Jul 20127 Apr 2015Biomet 3I, LlcMethods for placing an implant analog in a physical model of the patient's mouth
US901114615 Jun 201121 Apr 2015Biomet 3I, LlcComponents for use with a surgical guide for dental implant placement
US906991414 Sep 201230 Jun 2015Align Technology, Inc.Method and system for fabricating a wax model of a dental coping configured to fit a tooth preparation
US908938022 Jun 201228 Jul 2015Biomet 3I, LlcMethod for selecting implant components
US908938218 Oct 201228 Jul 2015Biomet 3I, LlcMethod and apparatus for recording spatial gingival soft tissue relationship to implant placement within alveolar bone for immediate-implant placement
US910836119 Sep 201418 Aug 2015Biomet 3I, LlcMethod for manufacturing dental implant components
US911382212 Oct 201225 Aug 2015Covidien LpCollimated beam metrology systems for in-situ surgical applications
US91577322 Jul 201413 Oct 2015Covidien LpMethods utilizing triangulation in metrology systems for in-situ surgical applications
US920494117 Oct 20138 Dec 2015Biomet 3I, LlcMethod of creating an accurate bone and soft-tissue digital dental model
US920853122 May 20128 Dec 20153M Innovative Properties CompanyDigital dentistry
US92613563 Jul 201416 Feb 2016Align Technology, Inc.Confocal surface topography measurement with fixed focal positions
US92613583 Jul 201416 Feb 2016Align Technology, Inc.Chromatic confocal system
US929919219 Jul 201129 Mar 2016Align Technology, Inc.Methods and systems for creating and interacting with three dimensional virtual models
US93455626 Aug 201324 May 2016Align Technology, Inc.Methods, systems and accessories useful for procedures relating to dental implants
US935164327 Jan 201431 May 2016Covidien LpSystems and methods for optical measurement for in-situ surgical applications
US940474030 Jun 20152 Aug 2016Align Technology, Inc.Method and apparatus for colour imaging a three-dimensional structure
US94086792 Jul 20099 Aug 2016Align Technology, Inc.Method, apparatus and system for use in dental procedures
US94279168 Apr 201130 Aug 2016Align Technology, Inc.Method for preparing a physical plaster model
US94395683 Jul 201413 Sep 2016Align Technology, Inc.Apparatus and method for measuring surface topography optically
US945203227 Jun 201327 Sep 2016Biomet 3I, LlcSoft tissue preservation temporary (shell) immediate-implant abutment with biological active surface
US9463081 *11 Jan 201211 Oct 2016Kabushiki Kaisya AdvanceIntraoral video camera and display system
US947458824 Jun 201525 Oct 2016Biomet 3I, LlcMethod and apparatus for recording spatial gingival soft tissue relationship to implant placement within alveolar bone for immediate-implant placement
US953907123 Oct 201310 Jan 2017Align Technology, Inc.Method and system for designing and producing dental prostheses and appliances
US954979413 Oct 201524 Jan 2017Align Technology, Inc.Method for manipulating a dental virtual model, method for creating physical entities based on a dental virtual model thus manipulated, and dental models thus created
US956102231 Jan 20137 Feb 2017Covidien LpDevice and method for optical image correction in metrology systems
US957917124 Oct 201328 Feb 2017Ivoclar Vivadent AgProcess for manufacturing a dental restoration part and a dental furnace for manufacturing the same
US959716511 Dec 201421 Mar 2017Align Technology, Inc.Method, system and model for indirect bonding
US965141929 May 201316 May 2017Align Technology, Inc.Speckle reduction method and apparatus
US966041827 Aug 201423 May 2017Align Technology, Inc.VCSEL based low coherence emitter for confocal 3D scanner
US966218530 Sep 201430 May 2017Biomet 3I, LlcUniversal scanning member for use on dental implant and dental implant analogs
US96688296 Mar 20136 Jun 2017Align Technology, Inc.Methods and systems for dental procedures
US96688344 Dec 20146 Jun 2017Biomet 3I, LlcDental system for developing custom prostheses through scanning of coded members
US967542928 Dec 201513 Jun 2017Align Technology, Inc.Confocal surface topography measurement with fixed focal positions
US967543013 Aug 201513 Jun 2017Align Technology, Inc.Confocal imaging apparatus with curved focal surface
US968383529 Dec 201020 Jun 2017Align Technology, Inc.System and method for scanning an intraoral cavity
US969383917 Jul 20144 Jul 2017Align Technology, Inc.Probe head and apparatus for intraoral confocal imaging using polarization-retarding coatings
US970039022 Aug 201411 Jul 2017Biomet 3I, LlcSoft-tissue preservation arrangement and method
US973077927 May 201415 Aug 2017Align Technology, Inc.Method and system for providing feedback data useful in prosthodontic procedures associated with the intra oral cavity
US975286728 Dec 20155 Sep 2017Align Technology, Inc.Chromatic confocal system
US978223825 Apr 201610 Oct 2017Align Technology, Inc.Methods, systems and accessories useful for procedures relating to dental implants
US979534516 Oct 201424 Oct 2017Biomet 3I, LlcMethod for pre-operative visualization of instrumentation used with a surgical guide for dental implant placement
US20130188185 *8 Jan 201325 Jul 2013Vita Zahnfabrik H. Rauter Gmbh & Co. KgMiniaturized system and method for measuring optical characteristics
US20130286174 *11 Jan 201231 Oct 2013Kabushiki Kaisya AdvanceIntraoral video camera and display system
Classifications
International ClassificationA61B1/24, A61C9/00, A61B5/107, A61C13/00, G01B11/24
Cooperative ClassificationA61B1/00096, A61C5/77, A61B1/06, A61C9/0066, G01B11/24, A61B5/0064, G01B11/25, A61B5/1077, A61C13/0004, A61B5/4547, A61C9/0053, A61B5/0088, A61B1/24
European ClassificationA61B5/00P1A, A61C9/00E3L5, G01B11/25, A61B5/00P12D, A61C13/00C1, A61B5/107L, G01B11/24
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