CN116295103A - Optical non-contact high-gradient profile measuring device - Google Patents
Optical non-contact high-gradient profile measuring device Download PDFInfo
- Publication number
- CN116295103A CN116295103A CN202310260931.4A CN202310260931A CN116295103A CN 116295103 A CN116295103 A CN 116295103A CN 202310260931 A CN202310260931 A CN 202310260931A CN 116295103 A CN116295103 A CN 116295103A
- Authority
- CN
- China
- Prior art keywords
- axis
- measurement
- displacement
- interference
- laser
- 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.)
- Pending
Links
- 230000003287 optical effect Effects 0.000 title claims abstract description 24
- 238000006073 displacement reaction Methods 0.000 claims abstract description 120
- 238000005259 measurement Methods 0.000 claims abstract description 114
- 230000033001 locomotion Effects 0.000 claims abstract description 98
- 239000006185 dispersion Substances 0.000 claims abstract description 44
- 230000003595 spectral effect Effects 0.000 claims abstract description 43
- 239000013307 optical fiber Substances 0.000 claims abstract description 16
- 238000001514 detection method Methods 0.000 claims abstract description 8
- 238000005305 interferometry Methods 0.000 claims description 13
- 230000007613 environmental effect Effects 0.000 claims description 9
- 239000000523 sample Substances 0.000 claims description 5
- 238000006243 chemical reaction Methods 0.000 claims description 4
- CPBQJMYROZQQJC-UHFFFAOYSA-N helium neon Chemical compound [He].[Ne] CPBQJMYROZQQJC-UHFFFAOYSA-N 0.000 claims description 4
- 230000005540 biological transmission Effects 0.000 claims description 3
- 238000012545 processing Methods 0.000 claims description 3
- 230000008878 coupling Effects 0.000 claims description 2
- 238000010168 coupling process Methods 0.000 claims description 2
- 238000005859 coupling reaction Methods 0.000 claims description 2
- 238000005516 engineering process Methods 0.000 abstract description 2
- 238000009434 installation Methods 0.000 abstract 1
- 238000000034 method Methods 0.000 description 7
- 238000004458 analytical method Methods 0.000 description 6
- 238000011156 evaluation Methods 0.000 description 5
- 238000005070 sampling Methods 0.000 description 5
- 238000000691 measurement method Methods 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- 238000004364 calculation method Methods 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 238000007667 floating Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 235000000405 Pinus densiflora Nutrition 0.000 description 1
- 240000008670 Pinus densiflora Species 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001739 density measurement Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
- G01B11/2441—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures using interferometry
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B26/00—Optical devices or arrangements for the control of light using movable or deformable optical elements
- G02B26/08—Optical devices or arrangements for the control of light using movable or deformable optical elements for controlling the direction of light
- G02B26/10—Scanning systems
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
- G02B27/09—Beam shaping, e.g. changing the cross-sectional area, not otherwise provided for
- G02B27/0911—Anamorphotic systems
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
- G02B27/10—Beam splitting or combining systems
- G02B27/106—Beam splitting or combining systems for splitting or combining a plurality of identical beams or images, e.g. image replication
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/24—Coupling light guides
- G02B6/42—Coupling light guides with opto-electronic elements
- G02B6/4296—Coupling light guides with opto-electronic elements coupling with sources of high radiant energy, e.g. high power lasers, high temperature light sources
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E30/00—Energy generation of nuclear origin
- Y02E30/30—Nuclear fission reactors
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Length Measuring Devices By Optical Means (AREA)
Abstract
The invention relates to an optical non-contact high-gradient profile measuring device, and belongs to the field of precise measurement. The device mainly comprises a precise motion executing module, a contour surface detecting module and a precise displacement measuring module. The invention uses a spectral dispersion confocal displacement measuring head with a certain installation inclination angle to realize the detection of a high-steepness profile, utilizes a two-dimensional orthogonal linear motion platform carrying measuring head to move according to a specified track, and combines the rotation of a measured part on a precise rotating shaft to realize the three-dimensional profile scanning. The device adopts the multi-axis double-frequency laser interference ranging of optical fiber light guide to carry out high-precision measurement on the displacement of the measuring head and realize the compensation of Abbe error by combining the reference frame technology. The measuring device has a simplified structure, and can realize ultra-precise measurement of high-gradient precise parts.
Description
Technical Field
The invention belongs to the field of precision measurement, and particularly relates to an optical non-contact high-gradient profile measuring device.
Background
Along with the wide development of precision engineering, the demands for precision parts are also continuously increased. The geometric outline precision of the part is often a core technical index, the quality and performance of the part are determined, and the key point of obtaining the high-quality outline is to provide reliable and effective precise measurement for guiding manufacturing and evaluating the quality, so that higher requirements are put on the precise outline measurement technology and device.
Currently, commercial contour detection devices can be classified into the following types according to implementation methods: contact profile scanning, three-coordinate measurement, and non-contact optical scanning.
The contact profile scanning method uses a mechanical gauge head and a measurement reference standard to scan the profile of an object along a one-dimensional direction. During measurement, the measuring head is kept in contact with the measured surface; when scanning along a straight line, the change of the contour height can lead to the displacement of the mechanical measuring head, the displacement can be accurately measured by a sensor, and the contour value can be calculated and obtained by combining the geometric relationship of the measuring head structure. The method has the advantages of simple structure and easy realization, but has the defects of small measurement dimension, complex adjustment, limited rise of the measurable contour, surface damage risk and the like.
The three-coordinate measuring method is to touch the surface of the measured part through a mechanical or optical measuring head, move and record the space position of the measuring head by utilizing three linear motion shafts which are mutually perpendicular and are provided with grating rulers, and obtain the coordinates of measuring points so as to obtain the contour value. The three-coordinate measuring machine has stronger universality and automation degree, but generally adopts a point-by-point measurement mode, and has lower measurement efficiency and sampling density; the instrument adopts a grating ruler to carry out displacement measurement, has limited precision and does not meet the Abbe principle. The traditional three-coordinate measuring machine is improved by Japanese pine corporation to improve the measuring precision, the three-dimensional displacement measuring precision is improved by adopting a reference frame combined with laser interference ranging, a displacement measuring light path is designed at the equal-height position of a measuring head contact point to reduce the measured Abbe error, and the contour measuring precision within the highest hundred nanometers can be realized. But is limited by the gauge head system structure, which requires replacement of the gauge head and loses a certain accuracy when measuring a high-steepness profile; meanwhile, the measuring light path for eliminating Abbe error limits the size of the measured piece and the measurable rise to a certain extent; the three-dimensional orthogonal measurement mode makes the instrument measurement efficiency lower and bulky.
A typical representative instrument for non-contact optical scanning is the Luphos series profiler from taylor in the united states. The instrument adopts a four-axis structure, and realizes the coverage scanning of the non-contact optical multi-wavelength interference measuring head on the surface of the measured part through two linear motion axes and one rotary axis. Meanwhile, the additionally added measuring head rotating shaft enables the measuring head to always measure along the outline normal direction of the measured part, and requirements on the working angle and the focal point size of the measuring head are reduced. The method has the advantages of compact structure, high measurement precision and high efficiency, meets Abbe's principle, but the additional rotating shaft increases the structural complexity and the implementation difficulty of the instrument.
Disclosure of Invention
The technical problems to be solved by the invention are as follows: aiming at the high-precision contour detection requirement in the manufacturing of precision parts, the contour detection device with simple structure, high precision and high steepness is provided.
The technical scheme adopted for solving the technical problems is as follows: an optical non-contact high steepness profile measuring device comprising: a precision air-float rotary table 1, a horizontal rectilinear motion table 2, a vertical rectilinear motion table 3, a spectral dispersion confocal displacement measuring head 4, a laser 5, an optical fiber 6, a beam expander 7, a first spectroscope 8, a second spectroscope 9, a third spectroscope 10, a second turning mirror 11, a first turning mirror 12, a third interference mirror 13, a second interference mirror 14, a first interference mirror 15, a first beam coupler 16, a second beam coupler 17, a third beam coupler 18, a fourth beam coupler 19, a first receiver 20, a second receiver 21, a third receiver 22, a fourth receiver 23, an X-axis displacement measurement reference 24, a Z-axis displacement measurement reference 25, a mechanical platform 26 and a controller 27, wherein,
the precise air-float rotary table 1 is used for fixing the measured part 28 and executing precise rotary motion to realize the surface profile scanning of the measured part, and the rotary axis is defined as the Z axis of the measuring device;
the horizontal linear motion stage 2 is used for executing the horizontal direction motion and positioning of the spectral dispersion confocal displacement measuring head 4, so that the horizontal linear motion stage can scan the outline of the measured part 28 along the radial direction, and the moving direction of the horizontal linear motion stage is orthogonal to the Z axis;
the vertical linear motion platform 3 is arranged on the horizontal linear motion platform 2 and is used for carrying the spectral dispersion confocal displacement measuring head 4 to move and position along the vertical direction, and the moving direction is parallel to the Z axis;
the controller 27 drives the horizontal linear motion table 2 and the vertical linear motion table 3 to be linked, and controls the spectral dispersion confocal displacement measuring head 4 to scan and measure according to a specified track, so that the profile of the measured part 28 is always in the effective travel range of the spectral dispersion confocal displacement measuring head 4 during scanning;
the spectral dispersion confocal displacement measuring head 4 is arranged on the vertical linear motion table 3 and is used for carrying out non-contact detection on the surface profile information of the measured part 28;
the laser 5 is used for providing frequency-stabilized double-frequency helium-neon laser and carrying out interference measurement on the two-dimensional space position of the spectral dispersion confocal displacement measuring head 4, and the outgoing laser of the laser 5 is conducted to the vertical linear motion table 3 in the device through the optical fiber 6;
the beam expander 7 expands the laser transmitted by the optical fiber 6, and the expanded laser can be used for constructing an interference ranging light path;
the first spectroscope 8 is used for separating laser into a reference beam and a measuring beam, the reference beam is used for suppressing environmental errors and interference in interferometry, and the measuring beam is used for realizing the measurement of Z-axis 1-path displacement and X-axis 2-path displacement;
the second beam splitter 9 is used for splitting the laser into 2 beams, one beam is used for Z-axis interference ranging, and the other beam is used for X-axis interference ranging;
the third beam splitter 10 is used for splitting the X-axis measuring beam into 2 beams, wherein the 90-degree folded partial beam is an X-axis measuring beam 1;
the second turning mirror 11 is used for turning the laser beam transmitted by the third spectroscope 10 by 90 degrees to form an X-axis measuring beam 2;
the first turning mirror 12 is used for turning the laser beam reflected by the second beam splitter 9 by 90 degrees, and the direction of the turned laser beam is parallel to the Z axis of the device;
the third interferometer 13 is used for realizing the interferometry of the X-axis measuring beam 2;
the second interferometer 14 is used for realizing the interferometry of the X-axis measuring beam 1;
the first interferometer 15 is used for realizing the interferometry of Z-axis displacement;
the first beam coupler 16, the second beam coupler 17, the third beam coupler 18, and the fourth beam coupler 19 are configured to receive and couple the optical signals of the third interference mirror 13, the second interference mirror 14, the first interference mirror 15, and the first spectroscope 8, and transmit the optical signals to the first receiver 20, the second receiver 21, the third receiver 22, and the fourth receiver 23, so as to implement photoelectric conversion of the reference signal and the measurement signal;
the X-axis displacement measurement reference 24 is fixed on a stable mechanical platform 26, and the plane normal direction of the X-axis displacement measurement reference is defined as the X axis of the measurement device and is used as a component part of a double-frequency laser interference ranging light path to realize the measurement of double-light path displacement in the X direction;
the Z-axis displacement measuring reference 25 is fixed on a stable mechanical platform 26, and the plane normal direction of the Z-axis displacement measuring reference is parallel to the Z axis and is used as a component part of a double-frequency laser interference ranging light path to realize measurement of Z-direction displacement;
the controller 27 is used for realizing the programmed movement of the precise air-float rotary table 1, the horizontal linear movement table 2 and the vertical linear movement table 3, and the analysis and evaluation of the output signals of the precise air-float rotary table 1, the horizontal linear movement table 2, the vertical linear movement table 3, the first receiver 20, the second receiver 21, the third receiver 22 and the fourth receiver 23, and the analysis and evaluation of the measurement profile.
Furthermore, the laser emitted by the laser 5 is guided into a measuring light path in an optical fiber transmission mode, so that the light path layout and the structural form of the device are simplified.
Further, the dual-frequency laser is divided into four beams, one beam is used as a reference signal for measurement, and environmental errors and interference are restrained; one beam is used as a measurement signal of a Z axis to realize the measurement of the Z-direction displacement of the spectral dispersion confocal displacement measuring head 4; the two beams are used as measurement signals of an X-axis double light path, so that the measurement of the 4X-direction displacement of the spectral dispersion confocal displacement measuring head is realized, and the measured Abbe error is effectively compensated.
Further, the mounting of the spectrally dispersive confocal displacement probe 4 is at an oblique angle to the Z-axis to expand the steepness of the measurable profile.
The principle of the invention is as follows:
based on the principle of cylindrical coordinate measurement, three-dimensional contour rapid scanning measurement is realized through a triaxial motion mode. The surface profile of the measured object is detected in a non-contact way by using an obliquely-installed spectral dispersion confocal displacement measuring head, so that the range of the measurable slope is enlarged; the precise measurement of the position of the measuring point is realized by introducing a frequency-stabilized double-frequency laser to construct a precise interferometric displacement measuring light path in an optical transmission mode of optical fiber light guide, and the suppression of environmental errors and interference and the compensation of Abbe errors are realized by adopting a four-path light splitting mode. The device comprises:
the precise air-floating rotary table is used for fixing the measured part and executing precise rotary motion to realize the surface profile scanning of the measured part, and the rotary axis is defined as the Z axis of the measuring device.
And the horizontal linear motion stage is used for executing the horizontal motion and positioning of the spectral dispersion confocal displacement measuring head, so that the measuring head can scan the outline of the measured part along the radial direction, and the moving direction of the measuring head is orthogonal to the Z axis.
The vertical linear motion platform is arranged on the horizontal linear motion platform and is used for carrying the spectral dispersion confocal displacement measuring head to move and position along the vertical direction, and the moving direction of the vertical linear motion platform is parallel to the Z axis.
The controller drives the horizontal linear motion platform and the vertical linear motion platform to link, and controls the spectral dispersion confocal displacement measuring head to scan and measure according to a specified track, so that the profile of the measured part is always in the effective travel range of the spectral dispersion confocal displacement measuring head during scanning.
The spectral dispersion confocal displacement measuring head is arranged on the vertical linear motion table and is used for carrying out non-contact detection on the surface profile information of the measured part.
The laser is used for providing frequency-stabilized double-frequency helium-neon laser and is used for carrying out interference measurement of the two-dimensional space position of the spectral dispersion confocal displacement measuring head. The outgoing laser of the laser is conducted to a vertical linear motion table in the device through an optical fiber.
The beam expander expands the laser beam which is led out by the optical fiber, and the laser beam after the beam expansion can be used for constructing an interference ranging light path.
The first spectroscope is used for separating laser into a reference beam and a measuring beam, the reference beam is used for suppressing environmental errors and interference in interferometry, and the measuring beam is used for realizing measurement of Z-axis 1-path and X-axis 2-path displacement.
The second beam splitter is used for splitting the laser into 2 beams, one beam is used for Z-axis interference ranging, and the other beam is used for X-axis interference ranging.
The third beam splitter is used for dividing the X-axis measuring beam into 2 beams, wherein the 90-degree folded partial beam is the X-axis measuring beam 1.
The second turning mirror is used for turning the laser beam transmitted by the third spectroscope by 90 degrees to form an X-axis measuring beam 2.
The first turning mirror is used for turning the laser beam reflected by the second beam splitter by 90 degrees, and the direction of the turned laser beam is parallel to the Z axis of the device.
The third interferometer is used to perform interferometry of the X-axis measuring beam 2.
The second interferometer is used to perform interferometry of the X-axis measuring beam 1.
The first interferometer is used to effect interferometry of Z-axis displacement.
The first beam coupler, the second beam coupler, the third beam coupler and the fourth beam coupler are used for receiving, coupling and transmitting optical signals of the third interference mirror, the second interference mirror, the first interference mirror and the first spectroscope to the first receiver, the second receiver, the third receiver and the fourth receiver, and are used for realizing photoelectric conversion of reference signals and measurement signals.
The X-axis displacement measurement reference is fixed on a stable mechanical platform, and the plane normal direction of the X-axis displacement measurement reference is defined as the X axis of a measurement device and is used as a component part of a double-frequency laser interference ranging light path to realize the measurement of the displacement of the double light paths in the X direction.
The Z-axis displacement measurement reference is fixed on a stable mechanical platform, and the plane normal direction of the Z-axis displacement measurement reference is parallel to the Z axis and is used as a component part of a double-frequency laser interference ranging light path to realize measurement of Z-direction displacement.
The controller is used for realizing the programming motion of the precise air-float rotary table, the horizontal linear motion table and the vertical linear motion table, and the analysis and evaluation of the output signals of the precise air-float rotary table, the horizontal linear motion table, the vertical linear motion table, the first receiver, the second receiver, the third receiver and the fourth receiver, and the analysis and evaluation of the measurement profile.
Compared with the prior art, the invention has the following advantages:
(1) The laser is transmitted by adopting an optical fiber light guide mode, so that the optical path layout of the device is greatly simplified, and the structural complexity is reduced;
(2) By carrying out four-light path light splitting on the dual-frequency laser, not only is the accurate detection of Z-axis and X-axis displacement realized, but also the influence of environmental errors and interference on interference ranging is inhibited, and the compensation of Abbe errors is realized;
(3) The profile is measured by obliquely installing the spectral dispersion confocal displacement measuring head, so that the slope range of the measurable profile is greatly improved.
Drawings
FIG. 1 is a schematic diagram of an optical non-contact high-steepness profile measuring device.
Fig. 2 shows three measurement modes of device scan measurement, wherein fig. 2 (a) shows a spiral scan measurement mode, fig. 2 (b) shows a radial line measurement mode, and fig. 2 (c) shows a concentric ring measurement mode.
Fig. 3 shows a measurement method for measuring the convex surface and the concave surface by the device, wherein fig. 3 (a) shows a measurement method for measuring the convex surface by the device, and fig. 3 (b) shows a measurement method for measuring the concave surface by the device.
In the figure, 1 is a precise air floatation rotary table, 2 is a horizontal linear motion table, 3 is a vertical linear motion table, 4 is a spectral dispersion confocal displacement measuring head, 5 is a laser, 6 is an optical fiber, 7 is a beam expander, 8 is a first spectroscope, 9 is a second spectroscope, 10 is a third spectroscope, 11 is a second turning mirror, 12 is a first turning mirror, 13 is a third interference mirror, 14 is a second interference mirror, 15 is a first interference mirror, 16 is a first beam coupler, 17 is a second beam coupler, 18 is a third beam coupler, 19 is a fourth beam coupler, 20 is a first receiver, 21 is a second receiver, 22 is a third receiver, 23 is a fourth receiver, 24 is an X-axis displacement measurement reference, 25 is a Z-axis displacement measurement reference, 26 is a mechanical platform, 27 is a controller, and 28 is a measured part.
Detailed Description
The invention is further described below with reference to the drawings and detailed description.
As shown in fig. 1, the optical non-contact high-steepness profile measuring device is schematically structured, and is composed of a precise air-float rotary table 1, a horizontal rectilinear motion table 2, a vertical rectilinear motion table 3, a spectral dispersion confocal displacement measuring head 4, a laser 5, an optical fiber 6, a beam expander 7, a first spectroscope 8, a second spectroscope 9, a third spectroscope 10, a second turning mirror 11, a first turning mirror 12, a third interference mirror 13, a second interference mirror 14, a first interference mirror 15, a first beam coupler 16, a second beam coupler 17, a third beam coupler 18, a fourth beam coupler 19, a first receiver 20, a second receiver 21, a third receiver 22, a fourth receiver 23, an X-axis displacement measuring reference 24, a Z-axis displacement measuring reference 25, a mechanical platform 26 and a controller 27.
The precision air-floating rotary table 1 is horizontally fixed on a mechanical platform 26 and is used for executing the precision rotary motion of a measured part 28 and feeding back the angle value of the rotary motion in real time, and the rotary axis is defined as the Z axis of the measuring device.
The horizontal linear motion stage 2 is fixed on the mechanical platform 26 and is used for performing horizontal movement and positioning of the spectral dispersion confocal displacement measuring head 4 so as to scan the outline of the measured part 28 along the radial direction. The moving direction of the horizontal linear motion stage 2 is orthogonal to the Z axis, the verticality is in the order of magnitude of angle seconds, the positioning accuracy in the order of micrometers and the motion accuracy in the order of magnitude of angle seconds are achieved, and the travel of the horizontal linear motion stage can enable the dispersive confocal displacement measuring head 4 to cover the radial size range of the measured part 28.
The vertical linear motion platform 3 is arranged on the horizontal linear motion platform 2 and is used for carrying the spectral dispersion confocal displacement measuring head 4 to move and position along the vertical direction. The moving direction of the vertical linear motion platform 3 is parallel to the Z axis, the parallelism is in the micrometer level, the positioning accuracy in the micrometer level and the motion accuracy in the angle second level are achieved, and the travel of the vertical linear motion platform can enable the chromatic dispersion confocal displacement measuring head 4 to cover the sagittal height range of the measured part 28.
The controller 27 drives the horizontal rectilinear motion stage 2 and the vertical rectilinear motion stage 3 to be linked, and controls the spectral dispersion confocal displacement measuring head 4 to scan and measure according to a specified track, so that the profile of the measured part 28 is always in the effective travel range of the spectral dispersion confocal displacement measuring head 4 during scanning.
The spectral dispersion confocal displacement measuring head 4 is arranged on the vertical linear motion platform 3, the optical axis of the spectral dispersion confocal displacement measuring head is positioned in the XZ plane and forms an angle theta with the Z axis, and the angle theta can be generally set to be 2/3 of the maximum working inclination angle of the spectral dispersion confocal displacement measuring head 4 and can be appropriately increased or decreased in the range of the maximum working inclination angle according to measurement requirements. The spectral dispersion confocal displacement probe 4 should have displacement resolution of 10nm magnitude and measurement range of hundred micrometers magnitude so as to meet the range and precision requirements of the measurement device.
The laser 5 is used for providing a frequency-stabilized dual-frequency helium-neon laser, and the dual-frequency laser is coupled to the polarization maintaining fiber 6 at the beam emergence position of the laser.
The beam expander 7 expands the laser transmitted and emitted by the optical fiber 6 to 3-6 mm in a collimation way, and the laser direction after the beam expansion is parallel to the Z axis and coplanar with the XZ plane.
The first spectroscope 8 is used for separating the laser light into a reference beam and a measuring beam, wherein the reflected beam is received by the fourth receiver 23 as a reference signal for suppressing environmental errors and interference in interferometry; the transmitted beam is used for realizing the measurement of Z-axis 1-path displacement and X-axis 2-path displacement. The first beam splitter 8 may generally employ a beam splitting ratio of reflected light to transmitted light of 3: 7.
The second beam splitter 9 is used to split the laser light into 2 beams, one for Z-axis interference ranging and the other for X-axis interference ranging. The second beam splitter 9 may generally employ a beam splitting ratio of reflected light to transmitted light of 3: 7.
The third beam splitter 10 is used to split the X-axis measuring beam into 2 beams, and the 90 ° reflected beam is the X-axis measuring beam 1. The third beam splitter 10 may generally be a non-polarizing beam splitter with a 1:1 ratio of reflected light to transmitted light.
The second turning mirror 11 is used for turning the transmitted beam after the X-axis measuring beam is split by 90 degrees, and the turned beam is the X-axis measuring beam 2. The direction of the diverted laser beam is parallel to the X axis of the device.
The first turning mirror 12 is used for turning the reflected laser beam of the second beam splitter 9 by 90 degrees to form a Z-axis measuring light path. The direction of the diverted laser beam is parallel to the Z axis of the device.
The third interferometer 13 is used to perform interferometry of the X-axis measuring beam 2, and a single beam interferometer is used.
The second interferometer 14 is used to perform interferometry of the X-axis measuring beam 1, and a single beam interferometer is used.
The first interferometer 15 is used to perform interferometry of Z-axis displacement, and a single beam interferometer is used.
The distance between the X-axis measuring beam 1 and the X-axis measuring beam 2 is d, and the distance between the focal point of the spectral dispersion confocal displacement measuring head and the X-axis measuring beam 2 is s.
The first beam coupler 16, the second beam coupler 17, the third beam coupler 18, and the fourth beam coupler 19 are configured to receive and couple the optical signals of the third interference mirror 13, the second interference mirror 14, the first interference mirror 15, and the first spectroscope 8, and transmit the optical signals to the first receiver 20, the second receiver 21, the third receiver 22, and the fourth receiver 23, so as to implement photoelectric conversion of the reference signal and the measurement signal.
The X-axis displacement measurement reference 24 is a standard flat crystal in the shape of a bar, and is fixed on a stable mechanical platform 26 by plating a reflecting film on the surface. The normal line of the plane of the X-axis displacement measurement reference 24 is orthogonal to the Z-axis, and the perpendicularity is controlled to be in the order of angular seconds. The normal direction of the plane of the X-axis displacement measurement reference 24 is defined as the X-axis of the measurement device, and is used as a component part of a double-frequency laser interference ranging light path to realize the measurement of X-axis double-light path displacement.
The Z-axis displacement measurement reference 25 is a bar-shaped standard flat crystal, a reflecting film is plated on the surface of the Z-axis displacement measurement reference 25, the Z-axis displacement measurement reference is fixed on a stable mechanical platform 26, the normal line of the plane of the Z-axis displacement measurement reference 25 is parallel to the Z axis, and the parallelism is controlled at the level of an angle second. The Z-axis displacement measuring reference 25 is used as a component part of a double-frequency laser interference ranging light path to realize measurement of Z-axis displacement.
The controller 27 has the functions of motion control, data acquisition and analysis. The device is used for realizing the programming motion of the precise air-float rotary table 1, the horizontal linear motion table 2 and the vertical linear motion table 3, the real-time acquisition, the processing and the analysis and the evaluation of the measurement profile of the output signals of the precise air-float rotary table 1, the horizontal linear motion table 2, the vertical linear motion table 3, the first receiver 20, the second receiver 21, the third receiver 22 and the fourth receiver 23.
The device performs the specific steps of measurement:
(1) Measurement mode selection
The device adopts a cylindrical coordinate measurement principle to carry out contour measurement, and a measurement mode can adopt: the spiral scan measurement mode, radial line measurement mode, and concentric ring measurement mode are shown in fig. 2 (a), 2 (b), and 2 (c), respectively.
In the spiral line measurement mode, the precise air-float rotary table 1 always keeps uniform rotary motion, the horizontal linear motion table 2 moves along a radial line according to a specified speed, and the vertical linear motion table 3 follows, so that a spiral line scanning measurement track is formed; this measurement mode is particularly suitable for rapid measurement of a continuous and substantially axisymmetric contour of a surface.
The device in the radial line measurement mode performs scan tests on radial contours of different polar angles of the part 28 under test. The precise air floatation rotary table 1 is used for carrying the measured part 28 to rotate to different polar angles, the horizontal linear motion table 2 moves along radial lines according to a specified speed, the vertical linear motion table 3 follows, and contour data of each radial line are obtained; this mode is suitable for contour measurement with large change in height in the rotation direction, and the sampling area density is relatively low.
In the concentric ring measurement mode, the precise air-float rotary table 1 always keeps uniform rotary motion, the horizontal linear motion table 2 and the vertical linear motion table 3 move according to the appointed coordinate position and stop after being in place, and meanwhile, the device performs full-circle sampling; the mode is suitable for high-surface density measurement with continuous surface and basically axisymmetric contour, can reduce the influence of dynamic errors of a motion platform on measurement, but has relatively low measurement speed, and usually needs to combine a plurality of radial line contour data to carry out environmental error compensation.
(2) Setting of measurement parameters
1. Contour parameter information of the part under test 28 is input to generate a theoretical scan trajectory. For the measurement of the convex surface and the concave surface, the horizontal linear motion stage 2 is driven to measure along a radial line of 0 degrees and a radial line of 180 degrees so as to achieve the purposes of increasing the measurable steepness and improving the precision, as shown in fig. 3 (a) and 3 (b).
2. The rotating speed of the precise air-float rotary table 1 of the measuring device is set according to the measuring requirement of the measured part 28, the moving speed and the moving range of the horizontal linear motion table 2 and the following mode of the vertical linear motion table 3.
3. The effective measurement area is set based on the measured part 28 size information or contour boundary information.
4. The data sampling rate, the filtering type and the filtering parameters of the measuring process are set.
(3) Implementation of the measurement
1. The rotation axis of the measured part 28 is adjusted and overlapped with the rotation axis of the precise air-float rotary table 1;
2. the horizontal linear motion stage 2 is driven to make the spectral dispersion confocal displacement measuring head 4 zero reference point (can be set as the stroke midpoint Lc thereof m ) On the Z axis, the vertical linear motion stage 3 is driven to enable the zero reference point of the spectral dispersion confocal displacement measuring head 4 to be positioned on the surface of the measured part 28.
3. The precise air-float rotary table 1, the horizontal linear motion table 2 and the vertical linear motion table 3 are driven to move according to the set measurement modes and parameters, and angle signals of the precise air-float rotary table 1 are synchronously acquired in real time
The spectral dispersion confocal displacement measuring head 4 measures displacement value Lc i Reference axis displacement signal Lref of laser interference ranging light path i X-axis measuring beam 1 displacement signal Lx1 i X-axis measuring beam 2 displacement signal Lx2 i Measuring Lz by Z-axis displacement measurement signal i 。
(4) Data processing
1. Acquisition of coordinate axis interference displacement values
X-axis and Z-axis interference displacement signal Lx1 i 、Lx2 i 、Lz i Is not in communication with the reference displacement signal Lref i Performing difference to obtain 1-bit of the compensated X-axis measuring beamShift Lx1c i X-axis measuring beam 2 displacement Lx2c i Z-axis displacement Lzc i 。
2. Compensation of Abbe error
The initial state is taken as a reference, and the displacement values corresponding to the X-axis measuring beam 1 and the X-axis measuring beam 2 are Lx1c respectively 0 、Lx2c 0 . The displacement values corresponding to the X-axis measuring beam 1 and the X-axis measuring beam 2 in the measuring process are Lx1c respectively i 、Lx2c i 。
Then the spectral dispersion confocal displacement probe 4 shifts Lx in the X-axis direction at the focus i The calculation formula of (2) is as follows:
Lx i ＝Lx2c i -((Lx1c i -Lx2c i )-(Lx1c 0 -Lx2c 0 ))*s/d
3. coordinate value calculation
Calculating coordinate values (x) corresponding to the surface sampling points according to the measurement principle, the system geometric parameters and the acquired displacement information i ，y i ，z i )：
Wherein Lc is i The reading is given for the spectral dispersion confocal displacement probe 4.
4. And calculating the contour error by means of model comparison or fitting according to the calculated discrete coordinate points.
The foregoing is merely illustrative of the embodiments of the present invention, and the scope of the present invention is not limited thereto, and any person skilled in the art will appreciate that modifications and substitutions are within the scope of the present invention, and the scope of the present invention is defined by the appended claims.
Claims (4)
1. An optical non-contact high steepness profile measuring device, comprising: a precise air floatation rotary table (1), a horizontal rectilinear motion table (2), a vertical rectilinear motion table (3), a spectral dispersion confocal displacement measuring head (4), a laser (5), an optical fiber (6), a beam expander (7), a first spectroscope (8), a second spectroscope (9), a third spectroscope (10), a second turning mirror (11), a first turning mirror (12), a third interference mirror (13), a second interference mirror (14), a first interference mirror (15), a first beam coupler (16), a second beam coupler (17), a third beam coupler (18), a fourth beam coupler (19), a first receiver (20), a second receiver (21), a third receiver (22), a fourth receiver (23), an X-axis displacement measurement reference (24), a Z-axis displacement measurement reference (25), a mechanical platform (26) and a controller (27),
the precise air-floatation rotary table (1) is used for fixing a measured part (28) and executing precise rotary motion to realize the surface profile scanning of the measured part, and the rotary axis is defined as the Z axis of the measuring device;
the horizontal linear motion table (2) is used for executing the horizontal direction motion and positioning of the spectral dispersion confocal displacement measuring head (4) so that the horizontal linear motion table can scan the outline of the measured part (28) along the radial direction, and the moving direction of the horizontal linear motion table is orthogonal to the Z axis;
the vertical linear motion platform (3) is arranged on the horizontal linear motion platform (2) and is used for carrying the spectral dispersion confocal displacement measuring head (4) to move and position along the vertical direction, and the moving direction of the vertical linear motion platform is parallel to the Z axis;
the controller (27) drives the horizontal linear motion table (2) and the vertical linear motion table (3) to be linked, and the spectral dispersion confocal displacement measuring head (4) is controlled to scan and measure according to a specified track, so that the profile of the measured part (28) is always in the effective travel range of the spectral dispersion confocal displacement measuring head (4) during scanning;
the spectral dispersion confocal displacement measuring head (4) is arranged on the vertical linear motion table (3) and is used for carrying out non-contact detection on the surface profile information of the measured part (28);
the laser (5) is used for providing frequency-stabilized double-frequency helium-neon laser, is used for carrying out interference measurement on the two-dimensional space position of the spectral dispersion confocal displacement measuring head (4), and the emergent laser of the laser (5) is conducted to a vertical linear motion table (3) in the device by an optical fiber (6);
the beam expander (7) expands the laser beam which is guided by the optical fiber (6), and the laser beam after the beam expansion can be used for constructing an interference ranging light path;
the first spectroscope (8) is used for separating laser into a reference beam and a measuring beam, the reference beam is used for suppressing environmental errors and interference in interferometry, and the measuring beam is used for realizing the measurement of Z-axis 1-path and X-axis 2-path displacement;
the second beam splitter (9) is used for splitting the laser into 2 beams, one beam is used for Z-axis interference ranging, and the other beam is used for X-axis interference ranging;
the third spectroscope (10) is used for dividing the X-axis measuring beam into 2 beams, wherein a 90-degree folded part of the beam is an X-axis measuring beam 1;
the second turning mirror (11) is used for carrying out 90-degree turning on the laser beam transmitted by the third spectroscope (10) to form an X-axis measuring beam 2;
the first turning mirror (12) is used for turning the laser beam reflected by the second beam splitter (9) by 90 degrees, and the direction of the turned laser beam is parallel to the Z axis of the device;
the third interference mirror (13) is used for realizing the interference measurement of the X-axis measuring beam 2;
the second interference mirror (14) is used for realizing the interference measurement of the X-axis measuring beam 1;
the first interference mirror (15) is used for realizing the interference measurement of Z-axis displacement;
the first beam coupler (16), the second beam coupler (17), the third beam coupler (18) and the fourth beam coupler (19) are used for receiving, coupling and transmitting optical signals of the third interference mirror (13), the second interference mirror (14), the first interference mirror (15) and the first spectroscope (8) to the first receiver (20), the second receiver (21), the third receiver (22) and the fourth receiver (23) so as to realize photoelectric conversion of reference signals and measurement signals;
the X-axis displacement measurement reference (24) is fixed on a stable mechanical platform (26), and the plane normal direction of the X-axis displacement measurement reference is defined as the X axis of the measurement device and is used as a component part of a double-frequency laser interference ranging light path to realize the measurement of X-direction double-light path displacement;
the Z-axis displacement measurement reference (25) is fixed on a stable mechanical platform (26), and the plane normal direction of the Z-axis displacement measurement reference is parallel to the Z axis and is used as a component part of a double-frequency laser interference ranging light path to realize measurement of Z-direction displacement;
the controller (27) is used for realizing the programming motion of the precise air-float rotary table (1), the horizontal linear motion table (2) and the vertical linear motion table (3), the precise air-float rotary table (1), the horizontal linear motion table (2), the vertical linear motion table (3), the first receiver (20), the second receiver (21), the third receiver (22) and the fourth receiver (23) and analyzing and evaluating the output signals of the real-time acquisition, the processing and the measurement profiles.
2. The optical non-contact high-steepness profile measuring device according to claim 1, wherein the laser light emitted by the laser (5) is guided into the measuring light path in an optical fiber transmission mode, so that the light path layout and the structural form of the device are simplified.
3. The optical non-contact high-steepness profile measuring device according to claim 1, wherein the dual-frequency laser is divided into four beams, one of which is used as a reference signal for measurement, to suppress environmental errors and interference; one beam is used as a measurement signal of a Z axis to realize the measurement of the Z-direction displacement of the spectral dispersion confocal displacement measuring head (4); the two beams are used as measurement signals of an X-axis double light path, so that the measurement of the X-direction displacement of the spectral dispersion confocal displacement measuring head (4) is realized, and the measured Abbe error is effectively compensated.
4. An optical non-contact high steepness profile measuring device according to claim 1, characterized in that the mounting of the spectrally dispersive confocal displacement probe (4) forms an inclination angle with the Z-axis to enlarge the steepness of the measurable profile.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310260931.4A CN116295103A (en) | 2023-03-17 | 2023-03-17 | Optical non-contact high-gradient profile measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310260931.4A CN116295103A (en) | 2023-03-17 | 2023-03-17 | Optical non-contact high-gradient profile measuring device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116295103A true CN116295103A (en) | 2023-06-23 |
Family
ID=86783035
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310260931.4A Pending CN116295103A (en) | 2023-03-17 | 2023-03-17 | Optical non-contact high-gradient profile measuring device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116295103A (en) |
-
2023
- 2023-03-17 CN CN202310260931.4A patent/CN116295103A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101581576B (en) | Method for measuring straightness accuracy and position thereof based on double frequency interference principle | |
| CN204747769U (en) | Laser on line measurement processes detection device | |
| CN2884141Y (en) | Laser, six freedom simultaneous measuring apparatus | |
| CN103411545B (en) | Based on the multiple axes system error modeling of freeform optics surface and measurement mechanism and method | |
| CN101581577B (en) | Device for measuring straightness accuracy and position thereof based on double frequency interference principle | |
| CN110081823B (en) | Five-degree-of-freedom geometric motion error measurement system of machine tool | |
| WO2016123812A1 (en) | Laser heterodyne interference linearity measuring apparatus and method having six-degrees-of-freedom detection | |
| CN201569419U (en) | Rapid surface quality measuring device | |
| EP0047237A1 (en) | Coordinate locating device | |
| JP3604944B2 (en) | Three-dimensional shape measuring machine and its measuring method | |
| CN105674914B (en) | Based on the freeform optics element shape measurement system and method from motion tracking | |
| CN110455226B (en) | Calibration system and method for laser collimation transceiving integrated straightness measurement | |
| CN104913733B (en) | The normal tracking mode non-spherical measuring method and system interfered based on multiwavelength laser | |
| CN101419044B (en) | Micron-nano grade three-dimensional measurement '331' system and measurement method thereof | |
| CN107462166B (en) | Long stroke, high precision displacement measurement method based on diffraction grating | |
| CN209842399U (en) | Calibrating device for geometric error of machine tool and corner positioning error of rotary table | |
| CN104864822A (en) | Method and system for normal tracking aspheric measurement based on laser interference | |
| CN114623784A (en) | Method and system for measuring straightness of long guide rail | |
| CN102003939A (en) | Two-dimensional measuring device based on double-frequency laser interference | |
| CN104848802A (en) | Differential confocal aspheric surface measurement method and system of normal tracking type | |
| CN115371587A (en) | Surface topography measuring device and method and object surface height calculating method | |
| US4538911A (en) | Three-dimensional interferometric length-measuring apparatus | |
| CN209706746U (en) | A kind of lathe five degree of freedom geometric moving error measuring system | |
| CN107339941A (en) | A kind of precise displacement monitoring system based on double-frequency laser interference principle | |
| CN203518952U (en) | Multi-axis system error modeling and measuring device based on optical free-form surface |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |