CN100365381C - Method and apparatus for enhancing measuring sensitivity of rotating corner - Google Patents

Method and apparatus for enhancing measuring sensitivity of rotating corner Download PDF

Info

Publication number
CN100365381C
CN100365381C CNB2005101327613A CN200510132761A CN100365381C CN 100365381 C CN100365381 C CN 100365381C CN B2005101327613 A CNB2005101327613 A CN B2005101327613A CN 200510132761 A CN200510132761 A CN 200510132761A CN 100365381 C CN100365381 C CN 100365381C
Authority
CN
China
Prior art keywords
light
wave plate
quarter
polarized light
reverberator
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.)
Expired - Fee Related
Application number
CNB2005101327613A
Other languages
Chinese (zh)
Other versions
CN1786659A (en
Inventor
匡翠方
冯其波
张志峰
张斌
陈士谦
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Beijing Jiaotong University
Original Assignee
Beijing Jiaotong University
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Beijing Jiaotong University filed Critical Beijing Jiaotong University
Priority to CNB2005101327613A priority Critical patent/CN100365381C/en
Publication of CN1786659A publication Critical patent/CN1786659A/en
Application granted granted Critical
Publication of CN100365381C publication Critical patent/CN100365381C/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Landscapes

  • Length Measuring Devices By Optical Means (AREA)

Abstract

The present invention relates to a method and an apparatus for enhancing the measuring sensitivity of rotating corners, which belongs to the technical field of photoelectric detection. A quarter wave plate, a reflector and a plane reflection mirror are orderly arranged on an optical axis in a moving unit after a stable collimation laser passes through a polarizer and a semi-transparent and semi-reflection mirror. Light passes through the reflector for two times and penetrates the quarter wave plate for four times by the plane reflection mirror, the measuring sensitivity is enhanced by two times based on the other patent, and meanwhile, the reflector is moved together with tracks; additive errors for measuring, which are caused by the movement of the reflector, are eliminated, the structure of the apparatus is compact to enhance the practicability of the apparatus. In addition, a receiver unit is arranged under the condition that light paths of measuring are not changed, so the paralleled real time high accuracy measurement of rolling angles, pitch angles and deflection angles is realized.

Description

A kind of method and apparatus that improves measuring sensitivity of rotating corner
Technical field
The invention belongs to the angle field of optical measuring technologies, particularly roll angle measurement method and rolling angle measurement instrument thereof.
Background technology
Roll angle is an important parameter in the error compensation.System such as lathe and three-coordinate measuring machine need measure roll angle, the angle of pitch and deflection angle in order to revise Abbe error in real time.In addition, in the Installation And Calibration of some workpiece, also need rolling angle measurement or location.
For line slideway roll angle measuring method, the laser polarization mensuration is the more a kind of method of studying at present.The Zhang Enyao of Tsing-Hua University etc. are 02123642.9 in China Patent No., patent name be a kind of based on orthogonal double polarizing light the roll angle photoelectric detecting method and the patent of device in a kind of roll angle photoelectric detecting method and device based on orthogonal double polarizing light disclosed, mainly be to utilize the brilliant light valve of timesharing modulation biliquid or two semiconductor laser timesharing to produce the pairwise orthogonal linearly polarized light, utilize polaroid as roll angle error Sensitive Apparatus, the light intensity that the roll angle error is converted to emergent light changes, by calculating the roll angle error.The method movable part has cable, makes troubles to in-site measurement.And China Patent No. is 01130893.1 to have adopted one 1/2nd wave plate as Sensitive Apparatus, and this method is measured the roll angle size by detected phase, but laser instrument costliness, control circuit and complexity thereof.The Chinese patent publication number is that 1687701A utilizes quarter-wave plate as the roll angle Sensitive Apparatus, utilizes the wollaston prism beam splitting simultaneously, obtains the roll angle size by surveying two beam splitting light intensity variations, but measures the insufficient sensitivity height.Wherein, back two kinds of methods all are reverberator to be fixed on the opposite side of measuring guide rail make light path pass through the roll angle Sensitive Apparatus twice, but reverberator is moved with the roll angle Sensitive Apparatus.The former is because reverberator moves the variation that can influence phase place with guide rail, brings additive error to measurement; Latter's reverberator moves brings variation can for two beam splitting light intensity difference, also brings additive error thereby give to measure.Therefore, these two kinds of methods all can not make reverberator move with measuring guide rail, thereby make apparatus structure not compact.
Summary of the invention
Purpose of the present invention and task are to propose a kind of roll angle measurement method and rolling angle measurement instrument thereof, not only making sensitivity is to improve 2 times again on the basis of 1687701A in patent publication No., and realized that reverberator moves with guide rail, and can eliminate reverberator and move the additive error of bringing to measurement with guide rail.Make apparatus structure more compact, to strengthen the practicality of instrument.
A kind of method that improves measuring sensitivity of rotating corner that the present invention proposes may further comprise the steps:
1) collimation laser that is sent by laser instrument produces linearly polarized light through polaroid;
2) this linearly polarized light becomes circularly polarized light through quarter-wave plate;
3) this circularly polarized light makes light become linearly polarized light through quarter-wave plate once more through reverberator;
4) this linearly polarized light is divided into two-beam through wollaston prism;
5) survey two beam splitting light with a detector, light intensity is converted into electric signal, and this electric signal is sent into computing machine after amplifying computing through signal processing circuit, the positive and negative reflection roll angle direction of its output voltage, the value of absolute value of voltage size reflection roll angle.
The linearly polarized light that above-mentioned steps 3 produces, on its light path, utilize a plane to penetrate mirror and make that light is reverse to be returned,, pass through quarter-wave plate again through quarter-wave plate, reverberator, incide the optical splitter in the fixed cell, the reflected light planoconvex lens of optical splitter incides wollaston prism.
A kind of device that improves measuring sensitivity of rotating corner, comprise: laser instrument, polaroid, quarter-wave plate, reverberator, wollaston prism, detector, signal processing circuit and computing machine, it is characterized in that, also comprise plane mirror, optical splitter, convex lens, described optical splitter is placed in the fixed cell, on the light path between polaroid and the mobile unit; Quarter-wave plate, reverberator and plane mirror are sequentially arranged in the mobile unit along the incident light direction in described; Described lens are placed between optical splitter and the wollaston prism or are placed between detector and the Wollaston; Described detector is placed on the focal plane of lens.
Described optical splitter comprises semi-transparent semi-reflecting lens.
Described reverberator comprises opal, prism of corner cube or right-angle prism.
The advantage that the present invention compares with prior art is: owing to placed a plane mirror on light path, make light pass through quarter-wave plate 4 times, measure roll angle sensitivity and be measuring method that patent publication No. 1687701A proposes 2 times, and light oppositely passes through reverberator 2 times, eliminated the additive error that reverberator brings to rolling angle measurement, realize reverberator moving on guide rail, made structure become more compact, made things convenient for in-site measurement.Not changing the light path condition, on the reflected light path of optical splitter, increase a receiving element simultaneously, can realize the measurement of the angle of pitch and deflection angle.Can be widely used in lathe line slideway and three coordinate measuring machine Abbe error real-Time Compensation.
Description of drawings
Fig. 1 is first embodiment of rolling angle measurement device of the present invention.
Fig. 2 is the influence principle schematic of reverberator rotation to incident light.
Fig. 3 rotates the catoptrical principle schematic that influences for reverberator.
Fig. 4 is second embodiment of rolling angle measurement device of the present invention.
Fig. 5 is three embodiment of rolling angle measurement device of the present invention.
Fig. 6 is first embodiment of the present invention and the angle of pitch, deflection angle while measurement mechanism.
Fig. 7 is second embodiment of the present invention and the angle of pitch, deflection angle while measurement mechanism.
Among the figure: 1 is laser instrument; 2 is polaroid; 3 is optical splitter; 4 is convex lens; 5 is wollaston prism; 6 is dual-quadrant detector; 7 is signal processing circuit; 8 is computing machine; 9 is plane mirror; 10 is quarter-wave plate; 11 is reverberator; 12 is pentagonal prism; 13 is semi-transparent semi-reflecting lens; 14 is concavees lens; 15 is position sensitive detector; 16 is convex lens; 101 is fixed cell; 201 is mobile unit; 301 is deflection unit.
Embodiment
Below in conjunction with accompanying drawing the present invention is further described.
Roll angle measurement method of the present invention is realized according to following principle:
In this method, adopting a plane mirror to make light path four times by the roll angle Sensitive Apparatus, polarization of light face corner is increased to octuple, is to improve 2 times once more on the basis of 1687701A in patent publication No..In addition, light oppositely passes through reverberator 2 times, can eliminate it and move the additive error of bringing to measurement on guide rail, thereby make measurement mechanism compacter.
Said method principle of the present invention is described as follows:
With Jones matrix the inventive method is analyzed, as shown in Figure 1, is established when initial, quarter-wave plate fast axle become with polarized light-π/4, the wollaston prism optical axis becomes π/4 placements with the outgoing polarized light.When mobile unit has the roll angle of , the Jones matrix form that can draw two light beams on the dual-quadrant detector is:
J()＝M w·B r·M(-)·R·M()·R·M(-)·R·M()B t·P·E 0 (1)
Incident light vector in the formula: E 0 = E x 0 E y 0 - - - ( 2 )
The polarizer is: P = 0 0 0 1 - - - ( 3 )
Semi-transparent semi-reflecting transmission, reflection matrix are respectively:
B t = 1 0 0 1 B r = 1 0 0 - 1 - - - ( 4 )
Wollaston prism is: M w = 2 2 1 1 - 1 1 - - - ( 5 )
Plane mirror and reverberator are: R = 1 0 0 - 1 - - - ( 6 )
Quarter-wave plate forward entrance, reverse incident are respectively:
Figure C20051013276100061
The Jones matrix substitution formula (1) of each device is calculated:
Figure C20051013276100062
Then the light intensity of two light beams is respectively on the detector:
Figure C20051013276100063
Be to obtain two light beam light intensity difference on the detector 6 to be
Figure C20051013276100064
Be =Δ I/8I 0(11)
More than calculate and consider that  is an a small amount of, all ignored its high-order in a small amount.This shows polarization of light face corner is increased to octuple that measuring sensitivity is that patent publication No. is 2 times of 1687701A.Because quarter-wave plate is a thin slice, its translation, pitching and deflection are to measuring almost not influence again.
Because the angle of pitch, the deflection angle of mobile unit also are a small amount of, and incident ray and reflection ray vertical plane catoptron 9 almost, so the translation of plane mirror and rotate and can ignore the reflections affect of polarized light.
In addition, because reverberator also is to move with mobile unit.Analyze theoretically below, twice reverse process reverberator (is example with the opal) can be eliminated the additive error that it brings to measurement.At first the translation of reverberator (opal) is almost not influence to measurement, even bring the translation of light also can eliminate its influence by scioptics 4 because plane mirror rotates.When opal has lift-over, obviously influence measuring hardly, and when opal has pitching and deflection, below to be deflected to example analysis.As shown in Figure 2, establish when initial, the angle of incident ray and opal optical axis is 0, when incident ray constant, opal with respect to the clockwise deflection α of incident light after, be equivalent to incident ray with respect to the counterclockwise deflection of opal α incide opal.Because the reverse characteristic of opal, make and incide plane mirror 9 glazed threads and will not deflect, and plane mirror 9 makes its reflected light deflection 2 α with opal deflection, can be obtained by Fig. 3, the light that at this moment incides for the second time opal with respect to the clockwise deflection of opal optical axis α.Inciding the optical axis of the light of opal with respect to opal as can be seen for twice by Fig. 2,3, just is that a positive negative bias has changeed α.Thereby the additive error that the deflection of having offset opal brings to rolling angle measurement.Wherein the angle of pitch also can similar analysis obtain, so the angle of pitch also can be eliminated the influence of measuring.
This shows that the present invention has realized that reverberator moves with mobile unit and do not influence measurement, thereby make the surveying instrument compact conformation.
Embodiment one (Fig. 1)
A kind of device that improves measuring sensitivity of rotating corner comprises: laser instrument 1, polaroid 2, optical splitter 3,, convex lens 4, wollaston prism 5, detector 6, signal processing circuit 7, computing machine 8, plane mirror 9, quarter-wave plate 10, reverberator 11;
Described optical splitter 3 is placed in the fixed cell 101, on the light path between polaroid 2 and the mobile unit 201; Quarter-wave plate 10, reverberator 11 and plane mirror 9 are sequentially arranged in the mobile unit 201 along the incident light direction in described; Described convex lens 4 are placed between optical splitter 3 and the wollaston prism 5 or are placed between detector 6 and the Wollaston 5; Described detector 6 is placed on the focal plane of convex lens 4.
Described reverberator also comprises: prism of corner cube or right-angle prism.
A kind of method step that improves measuring sensitivity of rotating corner is as follows:
1. the collimation laser that is sent by laser instrument 1 produces linearly polarized light through polaroid 2;
2. this linearly polarized light sees through and sees through optical splitter (semi-transparent semi-reflecting lens) again, incides quarter-wave plate 10, becomes linearly polarized light;
3. this circularly polarized light makes light become linearly polarized light through quarter-wave plate 10 once more through reverberator 11 (opal):
4. this polarized light returns through plane mirror is reverse once more, through quarter-wave plate 10, opal 11, passes through quarter-wave plate 10 again, incides the optical splitter 3 in the fixed cell 101.
5. the reflected light planoconvex lens 4 of optical splitter 3 incides wollaston prism 5 and is divided into two-beam;
6. survey two beam splitting light with a detector 6, light intensity is converted into electric signal, and this electric signal is sent into computing machine 8 after amplifying computing through signal processing circuit 7, the positive and negative reflection roll angle direction of its output voltage, the value of absolute value of voltage size reflection roll angle.
Embodiment two (Fig. 4):
It is basic identical with embodiment one with parameter that it forms device, and the position of wollaston prism 5 and convex lens 4 is exchanged, and also one obtains same measurement effect.
Embodiment three (Fig. 5):
It is basic identical with embodiment one with parameter that it forms device, just increases a steering unit 301 (pentagonal prism 12) between mobile unit 101 and fixed cell 201, makes device can directly apply to the rolling angle measurement of upright guide rail.
Embodiment four (Fig. 6):
It is basic identical with embodiment one with parameter that it forms device, and just the fixed cell 101 at device one increases optical splitter 13, concavees lens 14 and a two-dimentional position sensitive detector 15.When mobile unit has lift-over, pitching and deflection simultaneously, the light that reflects from mobile unit except roll angle information is arranged, the pitching of also having carried under one's arms, deflection angle information.Make reflected light be used for rolling angle measurement by optical splitter 13.Select suitable parameters to make concavees lens 14 and convex lens 4 form a lens combination, after transmitted light sees through concavees lens, incide two-dimentional position sensitive detector 15 and can realize that promptly the angle of pitch and deflection angle measure simultaneously.Distance is little should make in the selection of parameter between two lens as far as possible, reduce the instrument volume, and combined focal length is big, can increase pitching, deflection angle is measured sensitivity.This device can realize that three-dimensional perspective measures simultaneously.
Embodiment five (Fig. 7):
It is basic identical with embodiment four with parameter that it forms device, just increased convex lens 16 on the basis of device four.Wherein convex lens 4 are in order to prevent that light translation and deflection from causing light deviation detector 6, and convex lens 16 and concavees lens 14 are formed the measurement that lens combination are used for the angle of pitch and deflection angle.Can realize that also three-dimensional perspective measures simultaneously.On the basis of device four, five, increase steering unit 301, its three-dimensional corner that is applicable to upright guide rail is measured simultaneously.

Claims (4)

1. method that improves measuring sensitivity of rotating corner may further comprise the steps:
1) collimation laser that is sent by laser instrument (1) produces linearly polarized light through polaroid (2);
2) this linearly polarized light becomes circularly polarized light through quarter-wave plate (10);
3) this circularly polarized light makes light become linearly polarized light through quarter-wave plate (10) once more through reverberator (11);
4) this linearly polarized light is divided into two-beam through wollaston prism (5);
5) survey two beam splitting light with a detector (6), light intensity is converted into electric signal, and this electric signal is sent into computing machine after amplifying computing through signal processing circuit, the positive and negative reflection roll angle direction of its output voltage, the value of absolute value of voltage size reflection roll angle;
It is characterized in that, the linearly polarized light that step 3 produces, on its light path, utilize a plane mirror (9) to make that light is reverse to be returned, through quarter-wave plate (10), reverberator (11), pass through quarter-wave plate (10) again, incide the optical splitter (3) in the fixed cell (101), the reflected light planoconvex lens (4) of optical splitter (3) incides wollaston prism (5); The quick shaft direction of wherein said quarter-wave plate (10) becomes with direction of polarized light-π/4 angles, and the optical axis of wollaston prism (5) becomes π/4 angles with linearly polarized light.
2. device that improves measuring sensitivity of rotating corner, comprise: laser instrument, polaroid, quarter-wave plate, reverberator, wollaston prism, detector, signal processing circuit and computing machine, it is characterized in that, also comprise plane mirror (9), optical splitter (3), convex lens (4), described optical splitter (3) is placed in the fixed cell (101), on the light path between polaroid (2) and the mobile unit (201); Described plane mirror (9), quarter-wave plate (10) and reverberator (11) are sequentially arranged in the mobile unit (201) along the incident light direction, and make light earlier by quarter-wave plate (10), again by reverberator (11) retrodirective reflection, oppositely see through quarter-wave plate (10) once more, incide at last on the plane mirror (9), plane mirror (9) makes light return along the road; The fast axle of described quarter-wave plate (10) becomes with direction of polarized light-π/4 angles placement; The optical axis direction of described wollaston prism (5) becomes π/4 angles to place with the outgoing polarized light; Described convex lens (4) are placed between optical splitter (3) and the wollaston prism (5) or are placed between detector (6) and the wollaston prism (5); Described detector (6) is placed on the focal plane of convex lens (4).
3. the device of raising measuring sensitivity of rotating corner according to claim 2 is characterized in that, described optical splitter comprises semi-transparent semi-reflecting lens.
4. the device of raising measuring sensitivity of rotating corner according to claim 2 is characterized in that, described reverberator comprises opal, prism of corner cube or right-angle prism.
CNB2005101327613A 2005-12-28 2005-12-28 Method and apparatus for enhancing measuring sensitivity of rotating corner Expired - Fee Related CN100365381C (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CNB2005101327613A CN100365381C (en) 2005-12-28 2005-12-28 Method and apparatus for enhancing measuring sensitivity of rotating corner

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CNB2005101327613A CN100365381C (en) 2005-12-28 2005-12-28 Method and apparatus for enhancing measuring sensitivity of rotating corner

Publications (2)

Publication Number Publication Date
CN1786659A CN1786659A (en) 2006-06-14
CN100365381C true CN100365381C (en) 2008-01-30

Family

ID=36784206

Family Applications (1)

Application Number Title Priority Date Filing Date
CNB2005101327613A Expired - Fee Related CN100365381C (en) 2005-12-28 2005-12-28 Method and apparatus for enhancing measuring sensitivity of rotating corner

Country Status (1)

Country Link
CN (1) CN100365381C (en)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100460811C (en) * 2006-07-24 2009-02-11 北京交通大学 Method and device for improving straight line degree measurement sensitivity
CN101221044B (en) * 2008-01-29 2010-06-23 北京理工大学 Device and method for large distance light parallel regulation
CN101354243B (en) * 2008-09-03 2010-06-16 西安理工大学 Non-contact laser detection method of guide rail rolling angle
CN103486981B (en) * 2013-09-18 2016-04-13 浙江工业大学 High-precision angle proving installation under a kind of hot vacuum environment
CN105444700B (en) * 2015-12-25 2017-10-31 中国科学院光电研究院 A kind of many parallelism of optical axis detection means of multi-wavelength and detection method
CN110617779A (en) * 2019-09-27 2019-12-27 广东工业大学 Sensor sensitivity measuring method of high-precision surface morphology measuring machine
CN112254682B (en) * 2020-09-23 2022-07-01 重庆邮电大学 Three-dimensional angle measurement method of wide-range photoelectric autocollimator

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06229831A (en) * 1993-01-30 1994-08-19 Horiba Ltd Azimuthal polarimeter
JP2001141413A (en) * 1999-11-15 2001-05-25 Japan Science & Technology Corp Position measuring apparatus
CN1335483A (en) * 2001-08-31 2002-02-13 清华大学 Tumble angle measuring method and measurer
CN1396435A (en) * 2002-07-05 2003-02-12 清华大学 Photoelectric detection method and device based on orthogonal dual polarized light beams for rolled angle
CN1560563A (en) * 2004-02-25 2005-01-05 北京交通大学 Laser colimation system and method of automatic measuring light drift angle
CN1595170A (en) * 2004-06-25 2005-03-16 清华大学 Self-mixed intervention Doppler velometer based on two-frequency laser
CN1687701A (en) * 2005-06-07 2005-10-26 北京交通大学 Method and equipment for measuring rolling angle

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06229831A (en) * 1993-01-30 1994-08-19 Horiba Ltd Azimuthal polarimeter
JP2001141413A (en) * 1999-11-15 2001-05-25 Japan Science & Technology Corp Position measuring apparatus
CN1335483A (en) * 2001-08-31 2002-02-13 清华大学 Tumble angle measuring method and measurer
CN1396435A (en) * 2002-07-05 2003-02-12 清华大学 Photoelectric detection method and device based on orthogonal dual polarized light beams for rolled angle
CN1560563A (en) * 2004-02-25 2005-01-05 北京交通大学 Laser colimation system and method of automatic measuring light drift angle
CN1595170A (en) * 2004-06-25 2005-03-16 清华大学 Self-mixed intervention Doppler velometer based on two-frequency laser
CN1687701A (en) * 2005-06-07 2005-10-26 北京交通大学 Method and equipment for measuring rolling angle

Also Published As

Publication number Publication date
CN1786659A (en) 2006-06-14

Similar Documents

Publication Publication Date Title
CN101650166B (en) Laser interference system used for measuring micro roll angle
CN2884141Y (en) Laser, six freedom simultaneous measuring apparatus
CN104634283B (en) Laser heterodyne interference linearity measuring device and laser heterodyne interference linearity measuring method with six-degree-of-freedom detection
CN104180776B (en) High-resolution roll angle measurement method and device based on difference interference phase method
CN101846506B (en) Roll angle measurement method based on common path parallel beams
CN108168465B (en) A kind of optical path laser heterodyne interferometry roll angle high precision measuring device and method altogether
CN100365381C (en) Method and apparatus for enhancing measuring sensitivity of rotating corner
CN100573036C (en) The measuring method of a kind of film thickness and refractive index
CN100460811C (en) Method and device for improving straight line degree measurement sensitivity
CN109579780B (en) Polarization-based light splitting auto-collimation three-dimensional angle measuring device and method
CN101832821B (en) Method and device for measuring laser wavelength based on bound wavelength
CN104535019B (en) A kind of rolling angle measurement device and method of double diffraction grating difference interference
CN1285883C (en) Method and equipment for measuring rolling angle
CN105737765A (en) Four-freedom degree optical measuring head based on semiconductor laser assembly
CN102003935B (en) Environment compensation method for measurement employing laser tracker
CN102654392B (en) Roll angle measurement device and method based on array-type multiple reflections
CN104613900A (en) Full optical path drift compensation high-precision roll angle measuring method and device
CN103278110A (en) Compensation method for coupling error of guide rail
CN102679895B (en) Method for measuring center thickness of reflective confocal lens
CN103162645B (en) A kind of rolling measurement method and apparatus measured based on the ellipse degree of bias
CN107462166A (en) Long stroke based on diffraction grating, high precision displacement measuring method
CN109990736A (en) A kind of roll angle measurement method and device based on Stokes vector
CN102818541B (en) High-resolution rolling-angle measuring device and measuring method
CN200941068Y (en) Coherent polarization matrix measuring system
CN116164673A (en) Straightness interferometry method based on optical interference principle

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
C17 Cessation of patent right
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20080130

Termination date: 20101228