US20040042016A1 - Optical interferometer - Google Patents
Optical interferometer Download PDFInfo
- Publication number
- US20040042016A1 US20040042016A1 US10/654,183 US65418303A US2004042016A1 US 20040042016 A1 US20040042016 A1 US 20040042016A1 US 65418303 A US65418303 A US 65418303A US 2004042016 A1 US2004042016 A1 US 2004042016A1
- Authority
- US
- United States
- Prior art keywords
- light beam
- beam splitter
- optical
- incident
- reflection
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 230000003287 optical effect Effects 0.000 title claims abstract description 60
- 239000013307 optical fiber Substances 0.000 claims description 27
- 230000005540 biological transmission Effects 0.000 abstract description 13
- 238000005259 measurement Methods 0.000 description 7
- 239000000835 fiber Substances 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
- G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
- G01D5/266—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light by interferometric means
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B9/00—Measuring instruments characterised by the use of optical techniques
- G01B9/02—Interferometers
- G01B9/02055—Reduction or prevention of errors; Testing; Calibration
- G01B9/02056—Passive reduction of errors
- G01B9/02059—Reducing effect of parasitic reflections, e.g. cyclic errors
Definitions
- the present invention relates to an optical interferometer which is used, for example, in the field of the optical instrumentation engineering.
- FIG. 3 is a view showing an outline structural example of a conventional optical interferometer.
- numeral 1 is an optical fiber
- numeral 2 is a lens
- numeral 3 is an incident light beam
- numeral 4 is a beam splitter
- numerals 5 and 6 are reflection units
- numeral 7 is a light receiver.
- the optical interferometer converts, as shown in FIG. 3, the incident light beam 3 from the optical fiber 1 into a parallel light beam by the lens 2 , and branches the parallel light beam to two optical paths of a transmission light beam and a reflection light beam which are perpendicular to each other, by the beam splitter 4 , and the reflection light beams by the reflection units 5 and 6 placed in the respective optical paths at a right angle, are wave-combined again by the beam splitter 4 .
- the intensity change of the interference fringes is output by the light receiver 7 as an electric signal.
- the beam splitter 4 is perpendicularly arranged to the incident optical axis, however, the light beams reflected by the incident surface and the emitting surface of the beam splitter 4 are interfered with each other, or return to the fiber 1 , thereby, stable measurements are difficult.
- an object of the present invention is to eliminate such a reflection light beam, and to provide an optical interferometer which can conduct stable measurements.
- the invention according to a first aspect is an optical interferometer which is characterized by a structure provided with: an optical fiber in which a measured light beam is incident; a lens to convert the incident light beam from the optical fiber into a parallel light beam; a beam splitter which branches the incident light beam to two optical paths which are perpendicular to each other by a reflection light beam and a transmission light beam, and is arranged with a little inclination from the verticality to the incident light beam; a first reflection unit to reflect the light beam to a position which is moved in parallel with the reflected light beam from the beam splitter; a second reflection unit to reflect the light beam to a position which is moved in parallel with the transmitted light beam from the beam splitter; and the light receiver to receive the light wave-combined by the beam splitter.
- a reflector is representative, or instead of the reflector, for example, a corner cube can be used.
- the light receiving unit is a unit to output the intensity change of interference fringes as an electrical signal.
- the beam splitter is not perpendicularly arranged to the incident optical axis, but arranged with the inclination, the light beam reflected on the incident surface does not pass through the same optical path as the incident optical path, and therefore, the light beam does not return to the optical fiber.
- the light beam reflected on an emitting surface of the beam splitter does not pass through the same optical path in the beam splitter. Accordingly, the interference in the beam splitter can be avoided and stable measurements can be conducted.
- the invention according to a second aspect is the optical interferometer which is characterized by a structure provided with: an optical fiber in which a measured light beam is incident; a lens arranged at a position at which the incident optical axis is inclined by shifting the central axis of the optical fiber and the central axis of the lens; a beam splitter which branches the incident light beam to two optical paths which are perpendicular to each other by a reflection light beam and a transmission light beam; a second reflection unit to reflect the light beam to a position which is moved in parallel with the transmitted light beam from the beam splitter; and a light receiver to receive the light wave-combined by the beam splitter.
- a reflector is representative, or instead of the reflector, for example, a corner cube can be used.
- the light receiving unit is a unit to output the intensity change of interference fringes as an electrical signal.
- the invention of the second aspect in the same manner as the invention according to the first aspect, because the incident optical axis is inclined, the light beam reflected on the incident surface does not pass through the same optical path as the incident optical path, therefore, the light beam does not return to the optical fiber.
- the light beam reflected on an emitting surface of the beam splitter does not pass through the same optical path in the beam splitter. Accordingly, the interference in the beam splitter can be avoided and the stable measurements can be conducted.
- The, invention according to a third aspect is the optical interferometer according to either one of the first and second aspects, and is characterized by a structure in which the first and the second reflection units are reflectors.
- the first and the second reflection units are the optical interferometers, which are the reflectors
- the reflection light beam from the beam splitter is reflected to a position which is moved in parallel with the reflection light beam by the first reflector
- the transmission light beam from the beam splitter is reflected to a position which is moved in parallel with the transmission light beam by the second reflector, and these can be incident into the beam splitter.
- the invention according to a fourth aspect is the optical interferometer according to either one of the first and second aspects, and is characterized by a structure in which the first and the second reflection units are corner cubes.
- the first and the second reflection units are the optical interferometers, which are the corner cubes
- the reflection light beam from the beam splitter is reflected to a position which is moved in parallel with the reflection light beam by the first corner cube
- the transmission light beam from the beam splitter is reflected to a position which is moved in parallel with the transmission light by the second corner cube, and these can be incident into the beam splitter.
- the invention according to a fifth aspect is the optical interferometer according to either one of the first or second aspect, and is characterized by a structure in which the optical fiber is an obliquely polished optical fiber.
- the optical fiber is the optical interferometer, which is the obliquely polished optical fiber, the reflection on the connector end of the optical fiber is suppressed, and the returning light from the lens can be decreased.
- FIG. 1 is a view showing an outline structure of an optical interferometer according to a first embodiment of the invention.
- FIG. 2 is a view showing an outline structure of an optical interferometer according to a second embodiment of the present invention.
- FIG. 3 is a view showing an outline structure of a conventional optical interferometer.
- FIG. 1 and FIG. 2 embodiments of an optical interferometer according to the present invention will be described below.
- FIG. 1 is a view showing an outline structure of an optical interferometer according to a first embodiment of the present invention.
- numeral 1 is an optical fiber for outputting a light beam to be measured
- numeral 2 is a lens for converting the light beam from the optical fiber into a parallel light beam as an incident light beam 3
- numeral 4 is a beam splitter for branching the light beam to two optical paths perpendicular to each other to make a reflected light beam and a transmitted light beam
- numeral 5 is a first reflection unit for reflecting the reflected light beam to return the reflected light beam to the beam splitter
- numeral 6 is a second reflection unit for reflecting the transmitted light beam to return the transmitted light beam to the beam splitter
- numeral 7 is a light receiver for receiving the wave-combined light beam from the beam splitter 4 .
- the reflected light beam returned to the beam splitter is in parallel to the reflected light beam emitted from the beam splitter.
- the transmitted light beam returned to the beam splitter is in parallel to the transmitted light beam emitted from the beam splitter.
- the light beams reflected by the reflecting units 5 and 6 are again combined into a wave-combined beam by the beam splitter 4 to output the light receiver 7 .
- the reflection unit 5 is disposed on a stage, not shown, for moving the reflection unit at a constant speed.
- a difference is caused in the optical path length of the reflection light from the two reflection units 5 and 6 , and a change of the intensity of interference fringes is observed.
- the intensity change of the interference fringes is output by the light receiver 7 as an electric signal.
- the beam splitter 4 is arranged with inclination from a position that the light beam is introdued perpendicular to an incident surface of the beam splitter. Specifically, as shown in FIG. 1, when the incident beam is inclined by 1° with respect to a normal line of an incident surface of the beam splitter 4 , the light beam reflected on the incident surface of the beam splitter 4 does not path through the same optical path as the incident light beam, and advances toward a direction inclined by 2° with respect to the incident optical path.
- the reflected light beam returns to a position shifted by about 3.5 mm, and the reflected light beam does not return to the optical fiber 1 .
- the reflected light beam does not return through the same optical path in the beam splitter 4 , and the reflected light beam does not return to the optical fiber 1 .
- the light beam emitted from the beam splitter 4 is reflected to a position which is moved in parallel with the emitted light beam, by the reflectors 5 and 6 , and is incident again into the beam splitter 4 , and the wave-combined light is incident into the light receiver 6 .
- the beam splitter may be arranged in such a manner that the inclined angle of the incident beam is in a range of from 0.5° to 10° with respect to a normal line of an incident surface of the beam splitter 4 .
- the inclined angle is in a range of from 1° to 2°.
- FIG. 2 is a view showing an outline structure of an optical interferometer according to a second embodiment of the present invention.
- numeral 1 is an optical fiber
- numeral 2 is a lens
- numeral 3 is an incident light beam
- numeral 4 is a beam splitter
- numerals 5 and 6 are reflectors (the first and the second reflection units)
- numeral 7 is a light receiver.
- the elements 1 - 7 has the same structure as those of the first embodiment of the invention.
- central axes of the optical fiber 1 and the central axis of the lens 2 are shifted from each other. Accordingly, the incident light beam 3 which is made a parallel light beam by the lens 2 , is incident not perpendicularly to the beam splitter 4 , but with an angle with respect to the normal line of a incident surface of the beam splitter 4 . Therefore, the same effect as in the first embodiment can be obtained.
- the reflection unit is the reflector, however, the present invention is not limited to the reflector, but, instead of the reflector, the reflection unit such as a corner cube may be used.
- the optical interferometer according to the invention of the first aspect because the beam splitter is inclined, it can be eliminated that the reflection from the incident surface of the beam splitter and the reflection from the emitting surface return to the optical fiber, and the interference in the beam splitter occurs, and the stable measurement can be conducted.
- the optical interferometer according to the invention of the second aspect because the incident optical axis is inclined, as in the invention according to the first aspect, the reflection on the incident surface and the emitting surface can be suppressed and the stable measurement can be conducted.
- the reflected light from the beam splitter is reflected to a position which is moved in parallel with the reflected light by the first reflector, and on the one hand, the transmission light from the beam splitter is reflected to a position which is moved in parallel with the transmission light by the second reflector, and these can be incident to the beam splitter.
- the reflected light from the beam splitter is reflected to a position which is moved in parallel with the reflected light by the first corner cube, and on the one hand, the transmission light from the beam splitter is reflected to a position which is moved in parallel with the transmission light by the second corner cube, and these can be incident to the beam splitter.
- the optical fiber is the obliquely polished fiber, the returning light from the connector end is suppressed, and the stable measurements can be conducted.
Abstract
The optical interferometer in which the incident light beam 3 is branched into 2 optical paths of the reflection light and the transmission light which cross at right angle with each other by the beam splitter 4, and on each optical path, the reflection light is totally reflected by the first reflection unit 5, and the transmission light is totally reflected by the second reflection unit 6, and the reflection lights by both reflection units 5 and 6 are wave-combined again by the beam splitter 4, and received by the light receiver 7. The beam splitter 4 by which the incident light beam is wave-separated and wave-combined, is arranged with a little inclination from the vertical to the incident light beam.
Description
- 1. Field of the Invention
- The present invention relates to an optical interferometer which is used, for example, in the field of the optical instrumentation engineering.
- 2. Description of the Related Art
- FIG. 3 is a view showing an outline structural example of a conventional optical interferometer. In FIG. 3,
numeral 1 is an optical fiber,numeral 2 is a lens,numeral 3 is an incident light beam,numeral 4 is a beam splitter,numerals numeral 7 is a light receiver. - The optical interferometer converts, as shown in FIG. 3, the
incident light beam 3 from theoptical fiber 1 into a parallel light beam by thelens 2, and branches the parallel light beam to two optical paths of a transmission light beam and a reflection light beam which are perpendicular to each other, by thebeam splitter 4, and the reflection light beams by thereflection units beam splitter 4. - At this time, when a stage, not shown, on which the
reflection unit 5 is arranged, is moved at a constant speed, a difference is caused in the optical path length of the reflection light from the tworeflection units - The intensity change of the interference fringes is output by the
light receiver 7 as an electric signal. - As described above, in the conventional optical interferometer, the
beam splitter 4 is perpendicularly arranged to the incident optical axis, however, the light beams reflected by the incident surface and the emitting surface of thebeam splitter 4 are interfered with each other, or return to thefiber 1, thereby, stable measurements are difficult. - Accordingly, an object of the present invention is to eliminate such a reflection light beam, and to provide an optical interferometer which can conduct stable measurements.
- In order to solve the above problems, the invention according to a first aspect is an optical interferometer which is characterized by a structure provided with: an optical fiber in which a measured light beam is incident; a lens to convert the incident light beam from the optical fiber into a parallel light beam; a beam splitter which branches the incident light beam to two optical paths which are perpendicular to each other by a reflection light beam and a transmission light beam, and is arranged with a little inclination from the verticality to the incident light beam; a first reflection unit to reflect the light beam to a position which is moved in parallel with the reflected light beam from the beam splitter; a second reflection unit to reflect the light beam to a position which is moved in parallel with the transmitted light beam from the beam splitter; and the light receiver to receive the light wave-combined by the beam splitter.
- Herein, as the reflection unit, a reflector is representative, or instead of the reflector, for example, a corner cube can be used. The light receiving unit is a unit to output the intensity change of interference fringes as an electrical signal.
- As described above, according to the invention of the first aspect, because the beam splitter is not perpendicularly arranged to the incident optical axis, but arranged with the inclination, the light beam reflected on the incident surface does not pass through the same optical path as the incident optical path, and therefore, the light beam does not return to the optical fiber.
- Further, the light beam reflected on an emitting surface of the beam splitter does not pass through the same optical path in the beam splitter. Accordingly, the interference in the beam splitter can be avoided and stable measurements can be conducted.
- The invention according to a second aspect is the optical interferometer which is characterized by a structure provided with: an optical fiber in which a measured light beam is incident; a lens arranged at a position at which the incident optical axis is inclined by shifting the central axis of the optical fiber and the central axis of the lens; a beam splitter which branches the incident light beam to two optical paths which are perpendicular to each other by a reflection light beam and a transmission light beam; a second reflection unit to reflect the light beam to a position which is moved in parallel with the transmitted light beam from the beam splitter; and a light receiver to receive the light wave-combined by the beam splitter.
- Herein, as the reflection unit, a reflector is representative, or instead of the reflector, for example, a corner cube can be used. The light receiving unit is a unit to output the intensity change of interference fringes as an electrical signal.
- As described above, according to the invention of the second aspect, in the same manner as the invention according to the first aspect, because the incident optical axis is inclined, the light beam reflected on the incident surface does not pass through the same optical path as the incident optical path, therefore, the light beam does not return to the optical fiber.
- Further, the light beam reflected on an emitting surface of the beam splitter does not pass through the same optical path in the beam splitter. Accordingly, the interference in the beam splitter can be avoided and the stable measurements can be conducted.
- The, invention according to a third aspect is the optical interferometer according to either one of the first and second aspects, and is characterized by a structure in which the first and the second reflection units are reflectors.
- As described above, according the invention of the third aspect, because the first and the second reflection units are the optical interferometers, which are the reflectors, the reflection light beam from the beam splitter is reflected to a position which is moved in parallel with the reflection light beam by the first reflector, and on the one hand, the transmission light beam from the beam splitter is reflected to a position which is moved in parallel with the transmission light beam by the second reflector, and these can be incident into the beam splitter.
- The invention according to a fourth aspect is the optical interferometer according to either one of the first and second aspects, and is characterized by a structure in which the first and the second reflection units are corner cubes.
- As described above, according to the invention of the fourth aspect, because the first and the second reflection units are the optical interferometers, which are the corner cubes, the reflection light beam from the beam splitter is reflected to a position which is moved in parallel with the reflection light beam by the first corner cube, and on the one hand, the transmission light beam from the beam splitter is reflected to a position which is moved in parallel with the transmission light by the second corner cube, and these can be incident into the beam splitter.
- The invention according to a fifth aspect is the optical interferometer according to either one of the first or second aspect, and is characterized by a structure in which the optical fiber is an obliquely polished optical fiber.
- As described above, according to the invention according to the fifth aspect, because the optical fiber is the optical interferometer, which is the obliquely polished optical fiber, the reflection on the connector end of the optical fiber is suppressed, and the returning light from the lens can be decreased.
- FIG. 1 is a view showing an outline structure of an optical interferometer according to a first embodiment of the invention.
- FIG. 2 is a view showing an outline structure of an optical interferometer according to a second embodiment of the present invention.
- FIG. 3 is a view showing an outline structure of a conventional optical interferometer.
- Referring to FIG. 1 and FIG. 2, embodiments of an optical interferometer according to the present invention will be described below.
- First embodiment
- Initially, FIG. 1 is a view showing an outline structure of an optical interferometer according to a first embodiment of the present invention. As well as the conventional optical interferometer (refer to FIG. 3), in FIG. 1,
numeral 1 is an optical fiber for outputting a light beam to be measured,numeral 2 is a lens for converting the light beam from the optical fiber into a parallel light beam as anincident light beam 3,numeral 4 is a beam splitter for branching the light beam to two optical paths perpendicular to each other to make a reflected light beam and a transmitted light beam,numeral 5 is a first reflection unit for reflecting the reflected light beam to return the reflected light beam to the beam splitter,numeral 6 is a second reflection unit for reflecting the transmitted light beam to return the transmitted light beam to the beam splitter, andnumeral 7 is a light receiver for receiving the wave-combined light beam from thebeam splitter 4. - The reflected light beam returned to the beam splitter is in parallel to the reflected light beam emitted from the beam splitter. Also, the transmitted light beam returned to the beam splitter is in parallel to the transmitted light beam emitted from the beam splitter. The light beams reflected by the
reflecting units beam splitter 4 to output thelight receiver 7. - The
reflection unit 5 is disposed on a stage, not shown, for moving the reflection unit at a constant speed. When the stage is moved at the constant speed, a difference is caused in the optical path length of the reflection light from the tworeflection units light receiver 7 as an electric signal. - According to the first embodiment, the
beam splitter 4 is arranged with inclination from a position that the light beam is introdued perpendicular to an incident surface of the beam splitter. Specifically, as shown in FIG. 1, when the incident beam is inclined by 1° with respect to a normal line of an incident surface of thebeam splitter 4, the light beam reflected on the incident surface of thebeam splitter 4 does not path through the same optical path as the incident light beam, and advances toward a direction inclined by 2° with respect to the incident optical path. - Herein, when the distance between the
optical fiber 1 and thebeam splitter 4 is 10 cm, the reflected light beam returns to a position shifted by about 3.5 mm, and the reflected light beam does not return to theoptical fiber 1. Next, as for also the light beam reflected on an emitting surface of thebeam splitter 4, the reflected light beam does not return through the same optical path in thebeam splitter 4, and the reflected light beam does not return to theoptical fiber 1. The light beam emitted from thebeam splitter 4 is reflected to a position which is moved in parallel with the emitted light beam, by thereflectors beam splitter 4, and the wave-combined light is incident into thelight receiver 6. - Althogh the inclined angle is 1° in the first embodiment, the beam splitter may be arranged in such a manner that the inclined angle of the incident beam is in a range of from 0.5° to 10° with respect to a normal line of an incident surface of the
beam splitter 4. Preferably, the inclined angle is in a range of from 1° to 2°. - Second embodiment
- FIG. 2 is a view showing an outline structure of an optical interferometer according to a second embodiment of the present invention. As well as the conventional optical interferometer (refer to FIG. 3), in FIG. 2,
numeral 1 is an optical fiber,numeral 2 is a lens,numeral 3 is an incident light beam,numeral 4 is a beam splitter,numerals numeral 7 is a light receiver. The elements 1-7 has the same structure as those of the first embodiment of the invention. - According to the second embodiment, central axes of the
optical fiber 1 and the central axis of thelens 2 are shifted from each other. Accordingly, theincident light beam 3 which is made a parallel light beam by thelens 2, is incident not perpendicularly to thebeam splitter 4, but with an angle with respect to the normal line of a incident surface of thebeam splitter 4. Therefore, the same effect as in the first embodiment can be obtained. - In this connection, in the embodiments, the reflection unit is the reflector, however, the present invention is not limited to the reflector, but, instead of the reflector, the reflection unit such as a corner cube may be used.
- Further, besides, it is of course that the specific dimensional relationship or the like, may be appropriately modified.
- As described above, according to the optical interferometer according to the invention of the first aspect, because the beam splitter is inclined, it can be eliminated that the reflection from the incident surface of the beam splitter and the reflection from the emitting surface return to the optical fiber, and the interference in the beam splitter occurs, and the stable measurement can be conducted.
- According to the optical interferometer according to the invention of the second aspect, because the incident optical axis is inclined, as in the invention according to the first aspect, the reflection on the incident surface and the emitting surface can be suppressed and the stable measurement can be conducted.
- According to the optical interferometer according to the invention of the third aspect, because the first and the second reflection units are reflectors, as in the invention of the first aspect, the reflected light from the beam splitter is reflected to a position which is moved in parallel with the reflected light by the first reflector, and on the one hand, the transmission light from the beam splitter is reflected to a position which is moved in parallel with the transmission light by the second reflector, and these can be incident to the beam splitter.
- According to the optical interferometer according to the invention of the fourth aspect, because the first and the second reflection units are corner cubes, the reflected light from the beam splitter is reflected to a position which is moved in parallel with the reflected light by the first corner cube, and on the one hand, the transmission light from the beam splitter is reflected to a position which is moved in parallel with the transmission light by the second corner cube, and these can be incident to the beam splitter.
- According to the optical interferometer according to the invention of the fifth aspect, because the optical fiber is the obliquely polished fiber, the returning light from the connector end is suppressed, and the stable measurements can be conducted.
Claims (7)
1. An optical interferometer comprising:
an optical fiber for outputting alight beam to be measured;
a lens for converting the light beam from the optical fiber into a parallel light beam;
a beam splitter for branching the light beam to two optical paths perpendicular to each other to make a reflected light beam and a transmitted light beam, the beam splitter for combining the reflected light beam and the transmitted light beam to output a wave-combined light beam;
a first reflection unit for reflecting the reflected light beam to return the reflected light beam to the beam splitter, in which the reflected light beam returned to the beam splitter is in parallel to the reflected light beam emitted from the beam splitter;
a second reflection unit for reflecting the transmitted light beam to return the transmitted light beam to the beam splitter, in which the transmitted light beam returned to the beam splitter is in parallel to the transmitted light beam emitted from the beam splitter; and
a light receiver for receiving the wave-combined light beam from the beam splitter,
wherein the incident beam is inclined with respect to a normal line of an incident surface of the beam splitter.
2. The optical interferometer according to claim 1 wherein a central axis of the optical fiber is different from a central axix of the lens to incline the light beam with respect to the normal line of the incident surface of the beam splitter.
3. The optical interferometer according to claim 1 , wherein the first and the second reflection units are reflectors.
4. The optical interferometer according to claim 1 , wherein the first and the second reflection units are corner cubes.
5. The optical interferometer according to claim 1 , wherein the optical fiber is an obliquely polished optical fiber.
6. The optical interferometer according to claim 1 , wherein the inclined angle of the incident beam is in a range of from 0.5° to 10°.
7. The optical interferometer according to claim 1 , wherein the the inclined angle of the incident beam is in a range of from 1° to 2°.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/654,183 US20040042016A1 (en) | 2000-02-18 | 2003-09-03 | Optical interferometer |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2000041763A JP2001227906A (en) | 2000-02-18 | 2000-02-18 | Optical interferometer |
JPP.2000-041763 | 2000-02-18 | ||
US09/785,585 US6636317B2 (en) | 2000-02-18 | 2001-02-16 | Optical interferometer |
US10/654,183 US20040042016A1 (en) | 2000-02-18 | 2003-09-03 | Optical interferometer |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/785,585 Continuation US6636317B2 (en) | 2000-02-18 | 2001-02-16 | Optical interferometer |
Publications (1)
Publication Number | Publication Date |
---|---|
US20040042016A1 true US20040042016A1 (en) | 2004-03-04 |
Family
ID=18564938
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/785,585 Expired - Fee Related US6636317B2 (en) | 2000-02-18 | 2001-02-16 | Optical interferometer |
US10/654,183 Abandoned US20040042016A1 (en) | 2000-02-18 | 2003-09-03 | Optical interferometer |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/785,585 Expired - Fee Related US6636317B2 (en) | 2000-02-18 | 2001-02-16 | Optical interferometer |
Country Status (4)
Country | Link |
---|---|
US (2) | US6636317B2 (en) |
JP (1) | JP2001227906A (en) |
DE (1) | DE10107330A1 (en) |
GB (1) | GB2359378A (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6900899B2 (en) * | 2001-08-20 | 2005-05-31 | Agilent Technologies, Inc. | Interferometers with coated polarizing beam splitters that are rotated to optimize extinction ratios |
JP5317298B2 (en) * | 2010-09-08 | 2013-10-16 | 国立大学法人 香川大学 | Spectroscopic measurement apparatus and spectral measurement method |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4243323A (en) * | 1978-11-30 | 1981-01-06 | Nasa | Interferometer |
US5170223A (en) * | 1990-12-03 | 1992-12-08 | Advanced Fuel Research, Inc. | Device for blocking of divergent radiation, as in spectroscopy and instrument and method utilizing same |
US5325226A (en) * | 1989-02-17 | 1994-06-28 | U.S. Philips Corporation | Optical coherent receiver |
US5764361A (en) * | 1995-10-20 | 1998-06-09 | Nikon Corporation | Interferometer, adjusting method therefor, stage apparatus having the interferometer, and exposure apparatus having the stage apparatus |
US6034773A (en) * | 1997-10-16 | 2000-03-07 | Mitutoyo Corporation | Length measuring machine and method using laser beams |
US6134003A (en) * | 1991-04-29 | 2000-10-17 | Massachusetts Institute Of Technology | Method and apparatus for performing optical measurements using a fiber optic imaging guidewire, catheter or endoscope |
US6381015B1 (en) * | 1997-05-26 | 2002-04-30 | Hitachi, Ltd. | Inspection apparatus using optical interferometer |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0650243B2 (en) | 1984-12-14 | 1994-06-29 | 株式会社日立製作所 | Light wave interferometer |
WO1991000495A1 (en) | 1989-06-30 | 1991-01-10 | Nauchno-Proizvodstvenny Kooperativ 'fokon' | Method and device for determining the thickness of a glass tube |
-
2000
- 2000-02-18 JP JP2000041763A patent/JP2001227906A/en active Pending
-
2001
- 2001-02-16 GB GB0103904A patent/GB2359378A/en not_active Withdrawn
- 2001-02-16 US US09/785,585 patent/US6636317B2/en not_active Expired - Fee Related
- 2001-02-16 DE DE10107330A patent/DE10107330A1/en not_active Withdrawn
-
2003
- 2003-09-03 US US10/654,183 patent/US20040042016A1/en not_active Abandoned
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4243323A (en) * | 1978-11-30 | 1981-01-06 | Nasa | Interferometer |
US5325226A (en) * | 1989-02-17 | 1994-06-28 | U.S. Philips Corporation | Optical coherent receiver |
US5170223A (en) * | 1990-12-03 | 1992-12-08 | Advanced Fuel Research, Inc. | Device for blocking of divergent radiation, as in spectroscopy and instrument and method utilizing same |
US6134003A (en) * | 1991-04-29 | 2000-10-17 | Massachusetts Institute Of Technology | Method and apparatus for performing optical measurements using a fiber optic imaging guidewire, catheter or endoscope |
US5764361A (en) * | 1995-10-20 | 1998-06-09 | Nikon Corporation | Interferometer, adjusting method therefor, stage apparatus having the interferometer, and exposure apparatus having the stage apparatus |
US6381015B1 (en) * | 1997-05-26 | 2002-04-30 | Hitachi, Ltd. | Inspection apparatus using optical interferometer |
US6034773A (en) * | 1997-10-16 | 2000-03-07 | Mitutoyo Corporation | Length measuring machine and method using laser beams |
Also Published As
Publication number | Publication date |
---|---|
DE10107330A1 (en) | 2001-09-27 |
JP2001227906A (en) | 2001-08-24 |
GB0103904D0 (en) | 2001-04-04 |
US20010026656A1 (en) | 2001-10-04 |
GB2359378A (en) | 2001-08-22 |
US6636317B2 (en) | 2003-10-21 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP2329218B1 (en) | Compact fiber-optic geometry for a counter chirp fmcw coherent laser radar | |
EP0793079B1 (en) | Fiber coupled interferometric displacement sensor | |
US4941744A (en) | Integrated-photocircuit interferometer | |
JP3112198B2 (en) | Gradient index lens and optical receiver | |
CN111442715B (en) | Heterodyne laser interferometer based on integral secondary light splitting component | |
CN101825712A (en) | 2 mu m all-fiber coherent laser Doppler wind finding radar system | |
JP5180594B2 (en) | Interferometer | |
CN112097647B (en) | Heterodyne grating displacement measuring device | |
US6636317B2 (en) | Optical interferometer | |
CN211426800U (en) | Optical fiber coherent detection device and coherent speed measurement system | |
CN112130130A (en) | Silicon optical chip and laser radar system | |
CN110763135A (en) | High-precision laser interferometer | |
CN215575639U (en) | Polarization-maintaining optical circulator and laser radar | |
CN115876090A (en) | Reflection type Fabry-Perot grating interference displacement measurement method and system | |
CN210604964U (en) | Optical fiber coherent Doppler detection system | |
US4726684A (en) | Measurement apparatus for optical transmission factor | |
JP4643828B2 (en) | Generation of electromagnetic pulse trains for testing optical fibers | |
CN112683175B (en) | Reading head, displacement measurement system and displacement measurement method | |
US20230175917A1 (en) | Sensor assembly for measuring at least a first torsion of a rotor blade of a wind turbine generator system | |
CN101246238B (en) | Adjustable DC full optical fiber interference method and system | |
JPH0961298A (en) | Low coherence reflectometer | |
CN115435693A (en) | Synchronous measurement method and system for out-of-plane two-degree-of-freedom displacement in plane | |
JPH01116522A (en) | Optical directional coupler | |
CN1097736C (en) | Optical fibre transmission system for laser interference rate meter | |
CN112097649A (en) | Heterodyne grating displacement measurement optical system |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |