CN112504164A - Measuring device and method capable of dynamically measuring surface shape of planar optical element - Google Patents
Measuring device and method capable of dynamically measuring surface shape of planar optical element Download PDFInfo
- Publication number
- CN112504164A CN112504164A CN202011537852.6A CN202011537852A CN112504164A CN 112504164 A CN112504164 A CN 112504164A CN 202011537852 A CN202011537852 A CN 202011537852A CN 112504164 A CN112504164 A CN 112504164A
- Authority
- CN
- China
- Prior art keywords
- optical element
- surface shape
- detector
- measuring
- light
- 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 104
- 238000000034 method Methods 0.000 title claims abstract description 28
- 238000005259 measurement Methods 0.000 claims abstract description 24
- 238000010008 shearing Methods 0.000 claims abstract description 5
- 238000012545 processing Methods 0.000 claims description 25
- 238000001228 spectrum Methods 0.000 claims description 12
- 230000005540 biological transmission Effects 0.000 claims description 8
- 238000001914 filtration Methods 0.000 claims description 7
- 238000004148 unit process Methods 0.000 claims description 5
- 230000008569 process Effects 0.000 abstract description 4
- 230000010363 phase shift Effects 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 238000012360 testing method Methods 0.000 description 3
- 238000001444 catalytic combustion detection Methods 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 238000003672 processing method Methods 0.000 description 2
- 238000005070 sampling Methods 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000005305 interferometry Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 230000008685 targeting Effects 0.000 description 1
- 238000012876 topography Methods 0.000 description 1
- 238000002834 transmittance Methods 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
-
- 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
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Length Measuring Devices By Optical Means (AREA)
Abstract
The invention provides a measuring device and a method capable of dynamically measuring the surface shape of a planar optical element, aiming at solving the technical problems of low measuring precision, small measuring dynamic range and poor measuring real-time performance of the existing measuring device for the surface shape of the planar optical element. The invention uses the laser, the spectroscope, the collimating objective, the attenuation plate, the far field aiming detector, the small hole, the ocular, the binary optical device and the detector to realize the dynamic high resolution measurement of the surface shape of the measured plane optical element, and the measuring process is not influenced by the external environment; the inclination information between the beams relatively incident to the surface of the measured plane optical element is measured in real time by using a far-field aiming detector, so that high-precision alignment is realized, and the follow-up high-precision measurement can be realized; the adopted binary optical device is a micro-lens array or a mixed modulation grating, the corresponding measurement principles are respectively a Hartmann-shack principle and a transverse shearing interference principle, and the phase-shifting interference method has a larger measurement dynamic range compared with the traditional phase-shifting interference method.
Description
Technical Field
The invention belongs to the field of optics, relates to a device and a method for measuring the surface shape of a planar optical element, and particularly relates to a device and a method capable of dynamically measuring the surface shape of the planar optical element.
Background
With the construction scale of high-power laser devices becoming larger, the number of planar optical elements used becomes larger. The beam quality and beam focusing performance in a laser device are severely affected by the planar optical element profile. Therefore, the demand of dynamic measurement of the surface external field of the planar optical element is increasingly pressing.
The traditional static phase-shifting interferometer driven by piezoelectric ceramics (such as a U.S. Zygo phase-shifting laser interferometer) is susceptible to air flow disturbance and vibration because a measured wavefront phase result is obtained by performing phase shifting on a time domain, and the requirement on the measurement environment is more severe particularly for large-aperture optical elements, so that the interferometer cannot meet the requirement on external field dynamic measurement.
In terms of dynamic measurement, the dynamic interferometer developed by ESDI corporation and us 4D corporation is mainly used as a representative. The dynamic phase-shifting interferometer developed by the ESDI company utilizes three CCDs to respectively collect phase-shifted interference images, and then synthesis calculation is carried out, so that the precision can be ensured, but because a test beam and a reference beam share a light path, the polarization interference is difficult to realize, the requirement on the response consistency of the three CCDs is higher, the calculation speed is low, the appearance volume is larger, the test efficiency is not high, the price is high, and the economy is poor. The dynamic phase shift interferometer developed by 4D company adopts the principle of polarized light interference, converts time domain phase shift into space domain phase shift through a mask plate (micro-polarizer array), thereby realizing dynamic interferometry, and because data sampling points are limited and are approximated by adjacent pixel points, the testing accuracy is limited, and the price is high, the cost is high, and the economy is poor. Meanwhile, the measurement dynamic ranges of the two interferometers are small.
In summary, the surface shape measurement of the planar optical element gradually progresses to the direction of dynamic, high resolution and large aperture. The measuring instruments commercially available on the market at present have limitations in measuring precision, measuring dynamic range and real-time performance in the surface shape measurement of the planar optical element.
Disclosure of Invention
The invention provides a measuring device and a method capable of dynamically measuring the surface shape of a planar optical element, aiming at solving the technical problems of low measuring precision, small measuring dynamic range and poor measuring real-time performance of the existing measuring device for the surface shape of the planar optical element.
The technical scheme adopted by the invention is as follows:
the measuring device capable of dynamically measuring the surface shape of the planar optical element is characterized in that: the system comprises a laser, a first spectroscope, a collimating objective, a second spectroscope, an attenuation plate, a far-field aiming detector, a small hole, an ocular, a binary optical device, a detector and an image data processing unit;
the first spectroscope is arranged on an output light path of the laser, the collimating objective lens is arranged on a transmission light path of a light beam output by the laser after being transmitted by the first spectroscope, and the second spectroscope, the attenuation plate and the far-field aiming detector are sequentially arranged on a reflection light path of a light beam emitted by the collimating objective lens after being reflected by the first spectroscope; the pinhole, the ocular, the binary optical device and the detector are sequentially arranged on a reflection light path of the emergent light beam of the first spectroscope after being reflected by the second spectroscope;
the binary optics is used for modulating an optical field incident on the binary optics;
the far-field aiming detector is used for detecting a far-field focal spot image which is reflected back from the measured plane optical element by self-alignment;
the detector is used for detecting the light field image modulated by the binary optical device;
the image data processing unit is used for processing a far-field focal spot image acquired by the far-field aiming detector to obtain an azimuth angle and a pitch angle between the beams relatively incident to the surface of the measured plane optical element; and the device is also used for processing the image acquired by the detector to obtain the surface shape three-dimensional information of the measured plane optical element.
Further, the binary optical device is a two-dimensionally arranged micro-lens array; the aperture and focal length of all the lenses in the microlens array are the same.
Further, the binary optical device is a plano-convex lens array which is arranged in two dimensions; the aperture and the focal length of all the plano-convex lenses in the plano-convex lens array are the same.
Further, the specific method for obtaining the three-dimensional information of the surface shape of the measured planar optical element by processing the image acquired by the detector by the image data processing unit is as follows:
step1, calculating the deviation delta x and delta y of the light spot centroid in each sub-aperture relative to the x and y directions of a reference position;
step2, calculating the average slope of the wave fronts in the x and y directions in the sub-aperture range divided by the micro lens array:
wherein f is the focal length of the plano-convex lens, SxIs the average slope of the wavefront in the x-direction, SyThe average slope of the wavefront in the y-direction;
step3, adding SxAnd SySubstituting the obtained surface shape into the finite difference model to calculate and obtain the surface shape of the planar optical element to be measured
Wherein N is a slight permeationThe number of rows and columns of the mirror array, h is the sub-aperture size of the micro-lens array,
the average slopes of the wave fronts in the x-direction and the y-direction within the sub-aperture with position (i, j) in the microlens array, respectively.
Or the binary optical device is a mixed modulation grating and is used for carrying out amplitude and phase modulation on the light field incident to the surface of the binary optical device, the size of a light-transmitting part of the binary optical device is 2 times that of a light-proof part, and the light-transmitting part carries out phase modulation on the light field incident to the surface of the binary optical device according to phases 0 and pi; the phases 0 and pi are alternately distributed in a checkerboard manner.
Further, the specific method for obtaining the three-dimensional information of the surface shape of the measured planar optical element by processing the image acquired by the detector by the image data processing unit is as follows:
step1, performing fast Fourier transform on an acquired interference image to acquire a spectrogram;
step2, extracting two positive first-level frequency spectrums in the orthogonal direction by using frequency domain filtering window functions respectively, wherein the frequency domain filtering window functions adopt Hamming functions which meet the following requirements:
in the formula: (x)0,y0) The coordinate of the center position of the primary spectrum is shown, and (x, y) are the coordinates of the primary spectrum in the x and y directions;
step3, calculating the extracted positive-level frequency spectrum by utilizing inverse Fourier transform to obtain the differential wavefront in the x and y directions
And
step4, differentiating the wavefront in the x and y directions
And
substituting the obtained surface shape into a finite difference model to calculate the surface shape of the measured plane optical element (11)
Wherein sh is the transverse shearing amount.
The invention also provides a method for measuring the surface shape of the planar optical element based on the measuring device capable of dynamically measuring the surface shape of the planar optical element, which is characterized by comprising the following steps:
the first step is as follows: aiming
Adjusting the azimuth and pitch of the measuring device to make the azimuth angle theta between the measured plane optical element and the surface light beam incident to the measured plane optical elementAzAnd a pitch angle thetaELRespectively less than 0.5', and the aiming task is completed;
wherein the azimuth angle thetaAzAnd a pitch angle thetaELThe method comprises the following steps:
the image data processing unit processes the far-field focal spot image acquired by the far-field aiming detector to obtain the offset (delta x) of the centroid coordinate of the light spot relative to the center of the target surfacem,Δym) The azimuth angle theta between the measured plane optical element and the light beam incident on the surface of the measured plane optical elementAzAnd a pitch angle thetaELRespectively as follows:
θAz＝Δxm/(2·fob)
θEL＝Δym/(2·fob)
in the formula (f)obIs the focal length of the collimating objective lens;
the second step is that: measuring
And the image data processing unit processes the image acquired by the detector to obtain the surface shape three-dimensional information of the measured plane optical element.
The invention has the advantages that:
1. the invention realizes the dynamic high-resolution measurement of the surface shape of the measured plane optical element by utilizing the laser, the spectroscope, the collimating objective, the attenuation plate, the far-field aiming detector, the small hole, the ocular lens, the binary optical device and the detector, the measurement process is not influenced by the external environment (air flow disturbance, vibration and the like), and the measurement precision is well ensured.
2. The invention uses the far-field aiming detector to measure the tilt information (azimuth angle and pitch angle) between the beams relatively incident to the surface of the measured plane optical element in real time, thereby realizing high-precision alignment and ensuring that the high-precision measurement can be realized subsequently.
3. The binary optical device can adopt a micro-lens array or a mixed modulation grating, so that the surface shape measurement of the measured plane optical element under different scales and resolutions can be realized.
4. The traditional phase shift method needs to perform fixed phase modulation in a time-sharing manner, acquire phase modulation images at each moment, and calculate to obtain the surface topography information of the measured plane optical element according to the phase modulation images at different moments, wherein the method is easily influenced by the environment (air disturbance and vibration); the invention can calculate the surface appearance information of the measured plane optical element by only acquiring the image once, so compared with the traditional phase shift interference method, the invention can carry out single exposure and real-time dynamic measurement, greatly improves the measurement efficiency and is not influenced by the environment (air disturbance and vibration).
5. The binary optical device adopted by the invention is a micro-lens array or a mixed modulation grating, the corresponding measurement principles are respectively a Hartmann-shack principle and a transverse shearing interference principle, and the method has a larger measurement dynamic range compared with the traditional phase-shift interference method.
6. The light path of the invention adopts a common light path design, thereby avoiding the use of a beam splitter prism and reducing the cost.
7. In the invention, the measuring laser beam is incident on the measured plane optical element after passing through the collimating objective lens, and the aperture of the collimating objective lens can be made larger, so the invention can measure the plane optical element with large aperture.
8. The invention has less manual links, no artificial subjective error and high-precision quantitative measurement.
9. Experiments prove that the method has high stability, good repeatability and high confidence of the measurement result.
10. The invention has good economical efficiency and high precision, and is more suitable for the inspection of production workshops.
Drawings
Fig. 1 is a schematic diagram of the principle of the present invention.
Fig. 2 is a schematic diagram of a binary optical device according to the present invention, (a) is a schematic diagram of a binary optical device being a microlens array, and (b) is a schematic diagram of a binary optical device being a hybrid modulation grating.
Fig. 3 is a diagram of the transmission function of a hybrid modulation grating, white for 0-phase modulation, black for pi-phase modulation, and gray for opaque parts.
Reference numerals:
1-a laser; 2-a first beam splitter; 3-a collimating objective lens and 4-a second spectroscope; 5-an attenuation plate; 6-far field aiming detector; 7-small holes; 8-ocular lens; 9-binary optics; 91-microlens array; 92-hybrid modulation grating; 10-a detector; 11-measured plane optical element.
Detailed Description
The invention is further described below with reference to the accompanying drawings.
As shown in fig. 1, the measuring apparatus capable of dynamically measuring the surface shape of a planar optical element provided by the present invention includes a laser 1, a first spectroscope 2, a collimator objective 3, a second spectroscope 4, an attenuation plate 5, a far-field aiming detector 6, a pinhole 7 (with an aperture smaller than 1mm), an eyepiece 8, a binary optical device 9, a detector 10, and an image data processing unit (not shown in the figure).
The first spectroscope 2 is arranged on an output light path of the laser 1, the collimating objective 3 and the measured plane optical element 11 are sequentially arranged on a transmission light path of a laser output light beam transmitted by the first spectroscope 2, and the second spectroscope 4, the attenuation plate 5 and the far-field aiming detector 6 are sequentially arranged on a reflection light path of an emergent light beam of the collimating objective 3 reflected by the first spectroscope 2; the pinhole 7, the ocular 8, the binary optical device 9 and the detector 10 are sequentially arranged on a reflection light path of the emergent light beam of the first spectroscope 2 after being reflected by the second spectroscope 4.
The laser 1 is output by a single-mode fiber, the required power is stable in a short period, and the wavelength can be customized according to actual requirements.
The binary optics 9 is used to modulate the light field incident thereon, and the binary optics 9 may employ a microlens array 91 or a hybrid modulation grating 92.
As shown in fig. 2 (a), the microlens array 91 is a two-dimensionally arranged plano-convex lens array in which parameters (aperture and focal length) of all the plano-convex lenses are the same.
As shown in fig. 2 (b), the hybrid modulation grating 92 performs amplitude and phase modulation on the light field incident on the surface thereof, in which the size (total area) of the light-transmitting portion is 2 times the size (total area) of the light-non-transmitting portion, and the light-transmitting portion performs phase modulation on the light field incident on the surface thereof in phases 0 and pi (checkerboard alternate distribution), as shown in fig. 3. The hybrid modulation grating 92 transmittance function is:
in the formula, d is grating pitch; a is the size (namely the light transmission area) of the light transmission part of the mixed modulation grating; rect is a rectangular function; comb is a Comb sampling function, (x, y) is a spatial coordinate, j2＝-1。
The far-field aiming detector 6 is used for detecting a far-field focal spot image which is reflected by the measured plane optical element 11 from collimation;
the detector 10 is used for detecting the light field image modulated by the binary optical device 9;
the image data processing unit is used for processing the far-field focal spot image acquired by the far-field aiming detector 6 to obtain the inclination information (azimuth angle and pitch angle) between the measured plane optical element 11 and the light beam relatively incident to the surface of the measured plane optical element. Meanwhile, the image data processing unit is further configured to process the image acquired by the detector 10 to obtain three-dimensional information of the surface shape of the measured planar optical element 11.
The specific working process and principle of the invention are as follows:
the laser 1 single-mode fiber output laser beam is transmitted through a first spectroscope 2, collimated through a collimating objective 3, and incident to a measured plane optical element 11, a light field carrying surface shape information of the measured plane optical element 11 is reflected through the measured plane optical element 11, then converged through the collimating objective 3, reflected through the first spectroscope 2, then reflected through a part of a second spectroscope 4, transmitted through the other part, a transmitted light beam passes through an attenuation plate 5 and is focused on a target surface of a far-field aiming detector 6, a reflected light beam sequentially passes through a filtering aperture 7 and an eyepiece 8 to be collimated, and then incident to a binary optical device 9, modulated through the binary optical device 9, and received by a detector 10.
The measuring device of the invention is divided into two stages: 1) aiming; 2) and (6) measuring.
1) Aiming
The image data processing unit processes the far-field focal spot image acquired by the far-field aiming detector 6 to obtain the offset (delta x) of the centroid coordinate of the light spot relative to the center of the target surfacem,Δym) The azimuth angle theta between the measured plane optical element 11 and the light beam incident on the surface thereofAzAnd a pitch angle thetaELRespectively as follows:
θAz＝Δxm/(2·fob) (2)
θEL＝Δym/(2·fob) (3)
in the formula (f)obIs the focal length of the collimator objective 3.
Adjusting the azimuth and pitch of the measuring device such that the azimuth angle θAzAnd a pitch angle thetaELLess than 0.5 "respectively, the targeting task is completed.
2) Measuring
Depending on the form of the binary optics 9, there are two modes of operation in the measurement phase.
Working mode 1: the binary optics 9 employs a microlens array 91
In this mode, the light beam incident on the surface of the microlens array 91 is modulated into a two-dimensional spot lattice, and a spot lattice image is acquired by the detector 10. The data processing method comprises the following steps:
step 1: calculating the deviation delta x and delta y of the light spot centroid in each sub-aperture relative to the x and y directions of the reference position; the reference positions x and y are positions where the error of the measuring device is calibrated in advance, and the calibration method is a method known in the field;
step 2: the average slopes of the wave fronts in the x and y directions within the sub-aperture range divided by the microlens array 91 are calculated:
wherein f is the focal length of the plano-convex lens, SxIs the average slope of the wavefront in the x-direction, SyIs the average slope of the wavefront in the y-direction.
Step3 reaction of SxAnd SySubstituting into finite difference model (formula 5), calculating to obtain surface shape of the planar optical element 11 to be measured
Wherein N is the number of rows and columns of the microlens array, h is the sub-aperture size of the microlens array,
the average slope of the wave front in the x direction in the sub-aperture with the position (i, j) in the micro lens array,
is the average slope of the wavefront in the y-direction within the sub-aperture with position (i, j) in the microlens array.
The working mode 2 is as follows: the binary optical device 9 adopts a hybrid modulation grating 92
In this mode, the light beam incident on the surface of the hybrid modulation grating 92 generates ± 1 st order diffracted lights in two orthogonal directions, and these four diffracted lights are displaced from each other and interfere with each other, and an interference image is acquired by the detector 10. The data processing method comprises the following steps:
step 1: performing Fast Fourier Transform (FFT) on the obtained interference image to obtain a spectrogram;
step 2: two positive first-level frequency spectrums in the orthogonal direction are extracted by using frequency domain filtering window functions respectively, and the frequency domain filtering window functions adopt Hamming window functions which meet the following requirements:
in the formula: (x)0,y0) Is the coordinate of the center position of the primary spectrum, and (x, y) is the coordinate of the x direction and the y direction of the primary spectrum.
Step3, calculating the extracted positive-level frequency spectrum by using Inverse Fast Fourier Transform (iFFT) to obtain differential wave fronts in the x and y directions
And
step4 differentiating the wavefront in the x, y directions
And
substituting into finite difference model (formula (7)) to calculate the surface shape of the measured planar optical element 11
Wherein sh is the transverse shearing amount.
Claims (7)
1. But measuring device of dynamic measurement plane optical element profile of face characterized in that: the device comprises a laser (1), a first spectroscope (2), a collimating objective (3), a second spectroscope (4), an attenuation plate (5), a far-field aiming detector (6), a small hole (7), an ocular (8), a binary optical device (9), a detector (10) and an image data processing unit;
the first spectroscope (2) is arranged on an output light path of the laser (1), the collimating objective (3) is arranged on a transmission light path of a laser output light beam transmitted by the first spectroscope (2), and the second spectroscope (4), the attenuation plate (5) and the far-field aiming detector (6) are sequentially arranged on a reflection light path of an emergent light beam of the collimating objective (3) reflected by the first spectroscope (2); the pinhole (7), the ocular (8), the binary optical device (9) and the detector (10) are sequentially arranged on a reflection light path of an emergent light beam of the first spectroscope (2) after being reflected by the second spectroscope (4);
a binary optical device (9) for modulating the light field incident thereon;
the far-field aiming detector (6) is used for detecting a far-field focal spot image which is reflected back from the measured plane optical element (11) in a self-alignment manner;
the detector (10) is used for detecting the light field image modulated by the binary optical device (9);
the image data processing unit is used for processing a far-field focal spot image acquired by the far-field aiming detector (6) to obtain an azimuth angle and a pitch angle between the light beams relatively incident to the surface of the measured plane optical element (11); and the device is also used for processing the image acquired by the detector (10) to obtain the surface shape three-dimensional information of the measured plane optical element (11).
2. The apparatus for dynamically measuring the surface shape of a planar optical element according to claim 1, wherein: the binary optical device (9) is a micro-lens array which is arranged in two dimensions; the aperture and focal length of all the lenses in the microlens array are the same.
3. The apparatus for dynamically measuring the surface shape of a planar optical element according to claim 2, wherein: the binary optical device (9) is a plano-convex lens array which is arranged in two dimensions; the aperture and the focal length of all the plano-convex lenses in the plano-convex lens array are the same.
4. The apparatus for dynamically measuring the surface shape of a planar optical element according to claim 3, wherein: the specific method for processing the image acquired by the detector (10) by the image data processing unit to obtain the surface shape three-dimensional information of the measured plane optical element (11) is as follows:
step1, calculating the deviation delta x and delta y of the light spot centroid in each sub-aperture relative to the x and y directions of a reference position;
step2, calculating the average slope of the wave fronts in the x and y directions in the sub-aperture range divided by the micro lens array (91):
wherein f is the focal length of the plano-convex lens, SxIs the average slope of the wavefront in the x-direction, SyThe average slope of the wavefront in the y-direction;
step3, adding SxAnd SySubstituting the obtained surface shape into a finite difference model to calculate and obtain the surface shape of the plane optical element (11) to be measured
Wherein N is the number of rows and columns of the microlens array, h is the sub-aperture size of the microlens array,
the average slopes of the wave fronts in the x-direction and the y-direction within the sub-aperture with position (i, j) in the microlens array, respectively.
5. The apparatus for dynamically measuring the surface shape of a planar optical element according to claim 1, wherein: the binary optical device (9) is a mixed modulation grating and is used for carrying out amplitude and phase modulation on the light field incident to the surface of the binary optical device, the size of a light transmission part of the binary optical device is 2 times that of a light-tight part, and the light transmission part carries out phase modulation on the light field incident to the surface of the binary optical device according to phases 0 and pi; the phases 0 and pi are alternately distributed in a checkerboard manner.
6. The apparatus for dynamically measuring the surface shape of a planar optical element according to claim 5, wherein: the specific method for processing the image acquired by the detector (10) by the image data processing unit to obtain the surface shape three-dimensional information of the measured plane optical element (11) is as follows:
step1, performing fast Fourier transform on an acquired interference image to acquire a spectrogram;
step2, extracting two positive first-level frequency spectrums in the orthogonal direction by using frequency domain filtering window functions respectively, wherein the frequency domain filtering window functions adopt Hamming functions which meet the following requirements:
in the formula: (x)0,y0) The coordinate of the center position of the primary spectrum is shown, and (x, y) are the coordinates of the primary spectrum in the x and y directions;
step3, calculating the extracted positive-level frequency spectrum by utilizing inverse Fourier transform to obtain the differential wavefront in the x and y directions
And
step4, differentiating the wavefront in the x and y directions
And
substituting the obtained surface shape into a finite difference model to calculate the surface shape of the measured plane optical element (11)
Wherein sh is the transverse shearing amount.
7. The method for measuring the surface shape of the planar optical element based on the measuring device capable of dynamically measuring the surface shape of the planar optical element as claimed in any one of claims 1 to 6, is characterized by comprising the following steps:
the first step is as follows: aiming
Adjusting the azimuth and pitch of the measuring device such that the azimuth angle theta between the measured plane optical element (11) and the light beam incident on the surface thereofAzAnd a pitch angle thetaELRespectively less than 0.5', and the aiming task is completed;
wherein the azimuth angle thetaAzAnd a pitch angle thetaELThe method comprises the following steps:
the image data processing unit processes the far-field focal spot image acquired by the far-field aiming detector (6) to obtain the offset (delta x) of the centroid coordinate of the light spot relative to the center of the target surfacem,Δym) The azimuth angle theta between the measured plane optical element (11) and the light beam incident on the surface of the measured plane optical element is determinedAzAnd a pitch angle thetaELRespectively as follows:
θAz＝Δxm/(2·fob)
θEL＝Δym/(2·fob)
in the formula (f)obIs the focal length of the collimating objective lens (3);
the second step is that: measuring
The image data processing unit processes the image acquired by the detector (10) to obtain the surface shape three-dimensional information of the measured plane optical element (11).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011537852.6A CN112504164A (en) | 2020-12-23 | 2020-12-23 | Measuring device and method capable of dynamically measuring surface shape of planar optical element |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011537852.6A CN112504164A (en) | 2020-12-23 | 2020-12-23 | Measuring device and method capable of dynamically measuring surface shape of planar optical element |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112504164A true CN112504164A (en) | 2021-03-16 |
Family
ID=74923498
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011537852.6A Pending CN112504164A (en) | 2020-12-23 | 2020-12-23 | Measuring device and method capable of dynamically measuring surface shape of planar optical element |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112504164A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113776679A (en) * | 2021-08-26 | 2021-12-10 | 浙江大学 | Misregistration deviation compensation method of shack Hartmann wavefront sensor |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20130010286A1 (en) * | 2010-12-24 | 2013-01-10 | Beijing Institute Of Technology | Method and device of differential confocal and interference measurement for multiple parameters of an element |
| CN102937513A (en) * | 2012-11-05 | 2013-02-20 | 上海激光等离子体研究所 | Method and system for monitoring three dimensional angle disturbance of optical gratings on line |
| CN104034416A (en) * | 2014-05-21 | 2014-09-10 | 中国科学院西安光学精密机械研究所 | High-dynamic-range laser far-field focal spot measuring device and method |
| CN107515101A (en) * | 2017-09-04 | 2017-12-26 | 中国电子科技集团公司第四十研究所 | The dynamic parameter calibrating installation and method of a kind of stab ilized electro-optical sight system stable measurement device |
| CN108204789A (en) * | 2016-12-17 | 2018-06-26 | 中国科学院长春光学精密机械与物理研究所 | For detecting the device and detection method of the shape splicing of heavy-calibre planar optical elements face |
| CN111664802A (en) * | 2020-06-03 | 2020-09-15 | 中国科学院西安光学精密机械研究所 | Semiconductor wafer surface morphology measuring device based on dynamic quantitative phase imaging |
| CN111912354A (en) * | 2020-07-28 | 2020-11-10 | 中国科学院西安光学精密机械研究所 | High-power laser cluster far-field combined focal spot measuring method and system |
-
2020
- 2020-12-23 CN CN202011537852.6A patent/CN112504164A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20130010286A1 (en) * | 2010-12-24 | 2013-01-10 | Beijing Institute Of Technology | Method and device of differential confocal and interference measurement for multiple parameters of an element |
| CN102937513A (en) * | 2012-11-05 | 2013-02-20 | 上海激光等离子体研究所 | Method and system for monitoring three dimensional angle disturbance of optical gratings on line |
| CN104034416A (en) * | 2014-05-21 | 2014-09-10 | 中国科学院西安光学精密机械研究所 | High-dynamic-range laser far-field focal spot measuring device and method |
| CN108204789A (en) * | 2016-12-17 | 2018-06-26 | 中国科学院长春光学精密机械与物理研究所 | For detecting the device and detection method of the shape splicing of heavy-calibre planar optical elements face |
| CN107515101A (en) * | 2017-09-04 | 2017-12-26 | 中国电子科技集团公司第四十研究所 | The dynamic parameter calibrating installation and method of a kind of stab ilized electro-optical sight system stable measurement device |
| CN111664802A (en) * | 2020-06-03 | 2020-09-15 | 中国科学院西安光学精密机械研究所 | Semiconductor wafer surface morphology measuring device based on dynamic quantitative phase imaging |
| CN111912354A (en) * | 2020-07-28 | 2020-11-10 | 中国科学院西安光学精密机械研究所 | High-power laser cluster far-field combined focal spot measuring method and system |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113776679A (en) * | 2021-08-26 | 2021-12-10 | 浙江大学 | Misregistration deviation compensation method of shack Hartmann wavefront sensor |
| CN113776679B (en) * | 2021-08-26 | 2022-08-23 | 浙江大学 | Misregistration deviation compensation method for shack Hartmann wavefront sensor |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112577446B (en) | In-place surface shape splicing measuring device and method for large-caliber planar optical element | |
| CN111751012B (en) | Dynamic high-resolution optical wavefront phase measurement method | |
| CN110057543B (en) | Wave surface measuring device based on coaxial interference | |
| US11635289B2 (en) | Surface shape measurement device and surface shape measurement method | |
| CN103115582B (en) | Based on the Michelson fluorescence interference micro-measurement apparatus of stimulated radiation | |
| CN106644105B (en) | Wavefront sensor, detection method and system based on double helix point spread function | |
| CN103592108A (en) | CCD chip modulation transfer function test device and method | |
| CN103115583B (en) | Based on the Mirau fluorescence interference micro-measurement apparatus of stimulated radiation | |
| CN101469976A (en) | Light wave interferometer apparatus | |
| CN116379961B (en) | Phase measurement system and method | |
| CN105333815A (en) | Super lateral resolution surface three-dimensional online interference measuring system based on spectral dispersion line scanning | |
| CN104460247A (en) | Alignment device and alignment method | |
| JP2024063078A (en) | Wavefront measurement device, wavefront measurement method, optical system, and manufacturing method of optical element | |
| CN112082490B (en) | Displacement sensor based on Talbot image and COMS camera structure | |
| CN112504164A (en) | Measuring device and method capable of dynamically measuring surface shape of planar optical element | |
| CN110631510B (en) | High-precision angle measuring device and method based on Michelson structure | |
| CN112013972B (en) | Shearing quantity calibration device and method for transverse shearing interference wavefront sensor | |
| CN109458959B (en) | Variable-inclination-angle phase-shift grazing incidence interferometer measuring device and method | |
| CN109458944A (en) | The absolute verifying attachment of plane and its detection method based on synchronous conjugation differential interferometry | |
| CN106352985A (en) | Asymmetric spatial heterodyne spectrometer structure | |
| US3432239A (en) | Optical instruments of the interference type | |
| CN110736543A (en) | Shearing amount calibration device and method for grating shearing interference wavefront sensor | |
| RU2536764C1 (en) | Method of interference microscopy | |
| JP3714853B2 (en) | Planar shape measuring method in phase shift interference fringe simultaneous imaging device | |
| CN112781727A (en) | Transverse shearing interference spectrum imager based on prism and imaging method |
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 | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210316 |
|
| RJ01 | Rejection of invention patent application after publication |