CN106247972B - The calibration system and scaling method of image deformation in a kind of interferometry - Google Patents

The calibration system and scaling method of image deformation in a kind of interferometry Download PDF

Info

Publication number
CN106247972B
CN106247972B CN201510962490.8A CN201510962490A CN106247972B CN 106247972 B CN106247972 B CN 106247972B CN 201510962490 A CN201510962490 A CN 201510962490A CN 106247972 B CN106247972 B CN 106247972B
Authority
CN
China
Prior art keywords
spherical crown
waffle slab
optical element
distortion
measuring means
Prior art date
Application number
CN201510962490.8A
Other languages
Chinese (zh)
Other versions
CN106247972A (en
Inventor
苗亮
张文龙
刘钰
马冬梅
金春水
Original Assignee
中国科学院长春光学精密机械与物理研究所
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 中国科学院长春光学精密机械与物理研究所 filed Critical 中国科学院长春光学精密机械与物理研究所
Priority to CN201510962490.8A priority Critical patent/CN106247972B/en
Publication of CN106247972A publication Critical patent/CN106247972A/en
Application granted granted Critical
Publication of CN106247972B publication Critical patent/CN106247972B/en

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01BMEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00Measuring arrangements characterised by the use of optical means
    • G01B11/24Measuring arrangements characterised by the use of optical means for measuring contours or curvatures
    • G01B11/2441Measuring arrangements characterised by the use of optical means for measuring contours or curvatures using interferometry

Abstract

The present invention relates to technical field of optical detection, more particularly to the calibration system of image deformation in a kind of interferometry, include the calibration system of image deformation in interferometry, including interferometric measuring means, adjustment mechanism, spherical crown waffle slab and data processing equipment, spherical crown waffle slab, for being demarcated into line distortion to the tested optical element;Adjustment mechanism adjustment optics is detected optical element and is in interferometric measuring means confocal interference test position, the optical axis coincidence of tested center of optical element, the geometric center of spherical crown waffle slab and interferometric measuring means, the reference axis of spherical crown waffle slab and the coordinate overlapping of axles of interferometric measuring means detector;Interferometric measuring means carry out interference detection;Data processing equipment calculates the face shape error of distortion function and tested optical element.The invention also includes the scaling methods of image deformation in interferometry.By the way that waffle slab is arranged, image deformation calibration is carried out, has been reached in the case where not destroying tested element, realizes the advantageous effect of image deformation calibration.

Description

The calibration system and scaling method of image deformation in a kind of interferometry

Technical field

The present invention relates to technical field of optical detection, more particularly in a kind of interferometry the scaling method of image deformation and Calibration system.

Background technology

Modern lithographic technologies require plane in lithographic objective system, spherical surface, the optical elements such as aspherical face shape error Root-mean-square value reach sub-nanometer magnitude, therefore the processing of lithographic objective systems for optical component side shape and absolute sense technology propose High requirement.In order to realize the sub-nanometer machining accuracy of optical component surface shape, in optical component surface shape error absolute sense Technology is realized on the basis of sub-nanometer accuracy of detection, it is necessary to which Accurate Calibration is imaged abnormal in the interferometry for face shape error detection Become, otherwise the face shape error testing result containing image deformation can introduce coordinate in guiding optics component side shape reconditioning process and reflect Error is penetrated, to reduce the machining accuracy of optical component surface shape.

In the prior art, there are two main classes for the scaling method of image deformation in interferometry:One kind is to be based on interferometry Device optical design parameters calculate image deformation (J.E.Hayden, and T.S.Lewis, " Distortion correction method for aspheric optical testing”,Proceedings of SPIE,4101,57(2000));It is another Class is, image deformation in rule-based grid mark point calibration interferometry (J.S.Taylor, P.Gabella, R.Hudyma, et.al.,“Final report for Lith 112high-NA optics for the Micro-Exposure tool (MET)”,UCRL-ID-146679(2001))。

Image deformation is calculated based on interferometric measuring means optical design parameters, is in known interferometric measuring means whole optics Under the premise of design parameter, ray tracing is carried out by optical design software (e.g., CodeV and Zemax), is surveyed to calculate interference Measure the image deformation of device.This method only needs to carry out ray tracing calculating, is not related to complicated ray machine processing and integrated adjustment Process, however be difficult to obtain commercial optical component (e.g., laser interferometer host and standard in interferometric measuring means under normal conditions Camera lens) detailed design parameter.In addition, this method can not reflect that interferometric measuring means draw in optical manufacturing and system adjustment process The image deformation entered.

Image deformation is made using in tested optical element surface in rule-based grid mark point calibration interferometry The grid type mark point of rule, grid type mark point are imaged together with tested optical element by interferometric measuring means.Due to dry Relating to measuring device, there are image deformations, and the imaging magnification of each mark point is different, by measuring each practical amplification of mark point Rate and the difference of ideal magnifying power are to correct the image deformation of interferometric measuring means.This method can demarcate interferometric measuring means Image deformation caused by being assembled due to optical design, optical manufacturing and system, however this method is needed in tested optical element table Face processes or deposition grid type mark point, the process may damage tested optical element surface, therefore is not suitable for high-precision The in situ imaging distortion calibration of tested optical element.

Therefore, there is an urgent need for one kind not destroying the measured optical unit surface, simple in structure, and high-precision interferometry may be implemented The method and system of middle image deformation in situ detection.

Invention content

The present invention is directed to overcome, the detecting system of image deformation in situ detection in existing interferometry is complicated, detection is smart Degree is not high and can destroy the technological deficiency of tested optical element surface in calibration, provides image deformation in a kind of interferometry Calibration system, including interferometric measuring means, adjustment mechanism, spherical crown waffle slab and data processing equipment, the spherical crown waffle slab On be distributed with index aperture and by the index aperture mark made of reference axis, the radius of curvature of the spherical crown waffle slab with to quilt It is identical to examine optical element radius of curvature, for being demarcated into line distortion to the tested optical element;

The adjustment mechanism is in the interferometric measuring means confocal interference for adjusting the tested optical element of the optics Test position, the tested optical element are detected regional center, the geometric center of the spherical crown waffle slab and the interferometry The optical axis coincidence of device, and adjust the coordinate of the reference axis and the interferometric measuring means ccd detector of the spherical crown waffle slab Overlapping of axles;

The interferometric measuring means, for carrying out interference detection to the spherical crown waffle slab and the tested optical element, Obtain the interference pattern of the interference pattern and the tested optical element of the spherical crown waffle slab index aperture;

The data processing equipment, for calculating distortion coordinate according to the interference diagram data of the spherical crown waffle slab index aperture With the functional relation of undistorted coordinate, distortion function model is obtained;Be additionally operable to according to the interference pattern of the tested optical element and The face shape error of the tested optical element is calculated in the distortion function model;

The interferometric measuring means are oppositely arranged with the adjustment mechanism, and the tested optical element is set to the adjustment In mechanism, the spherical crown waffle slab is set between the interferometric measuring means and the tested optical element.

Preferably, the spherical crown waffle slab is metal structure, the index aperture is conical through-hole.

Preferably, the adjustment structure includes turntable and five dimension adjustment platforms, the turntable is set to the five dimensions adjustment On platform;The five dimensions adjustment platform is used to adjust the spatial position of the tested optical element, makes the tested optical element and institute It states spherical crown waffle slab and is detected regional center and the interferometric measuring means optical axis coincidence;The turntable is for adjusting the spherical crown net The optical axis coincidence of the geometric center of panel and the interferometric measuring means.

Preferably, the spherical crown waffle slab further includes fixed structure, it is described for the spherical crown waffle slab to be fixed on On tested optical element.

Preferably, interferometric measuring means extraction spherical crown waffle slab centre mark hole and adjacent four index apertures is flat Equal pixel separation is amplified as ideal magnifying power, and using the unit pixel interval in all index apertures and centre mark hole as practical Rate calculates the spherical crown waffle slab index aperture distortion coordinate according to the spherical crown waffle slab index aperture diagram data of interference containing distortion Functional relation between undistorted coordinate obtains distortion function model.

Correspondingly, the invention also includes a kind of scaling method of image deformation in interferometry, include the following steps:

S1, adjustment are detected the confocal interference test position that optical element is in interferometric measuring means, make the tested optics Element surface blur-free imaging on ccd detector, the tested optical element are detected regional center and the interferometric measuring means Optical axis coincidence;

S2, spherical crown waffle slab is positioned between the interferometric measuring means and the tested optical element, the spherical crown Waffle slab side is contacted with the tested optical element surface, adjusts the geometric center of the waffle slab index aperture and the interference Measuring device optical axis coincidence, and the reference axis of the spherical crown waffle slab index aperture is made to be visited respectively with the interferometric measuring means CCD Survey the coordinate overlapping of axles of device;The spherical crown waffle slab is formed according to the radius of curvature and bore parameter designing of tested optical element, The spherical crown waffle slab is the impermeable photo structure with index aperture and reference axis;

S3, interference inspection is carried out to the spherical crown waffle slab and the tested optical element using the interferometric measuring means It surveys, obtains the interference pattern containing distortion of the spherical crown waffle slab index aperture;

S4, diagram data is interfered containing distortion according to the spherical crown waffle slab index aperture, and extracts spherical crown waffle slab centre mark Hole and the mean pixel interval of adjacent four index apertures are used as ideal magnifying power, by the unit of all index apertures and centre mark hole Pixel separation is used as practical magnifying power, calculates the function between the spherical crown waffle slab index aperture distortion coordinate and undistorted coordinate Relationship obtains distortion function model;

S5, the spherical crown waffle slab is removed, the tested optical element is done using the interferometric measuring means Measurement is related to, tested optical element interference pattern containing distortion is obtained;

S6, the interference pattern containing distortion using the distortion function model and the tested optical element, solve the tested light The undistorted interference pattern of element is learned, to obtain the face shape error in the tested optical element distortion interference pattern, is completed to described The distortion calibration of tested optical element.

Preferably, in the step S2, surface curvature that the spherical crown waffle slab is contacted with the tested optical element Radius is identical as tested optical element radius of curvature, while the label that can identify change in coordinate axis direction is made in X-axis and Y-axis Hole.

Preferably, the step S4 includes the following steps:

The noise spot of S41, removal spherical crown waffle slab index aperture interference pattern containing distortion;

S42, the arithmetic mean of instantaneous value by calculating each index aperture whole pixel coordinate of spherical crown waffle slab, acquire spherical crown grid Geometric center coordinates of each index aperture of plate containing distortion;

S43, amplified using spherical crown waffle slab centre mark hole and the mean pixel interval of adjacent four index apertures as ideal Rate, each index aperture and the unit pixel interval in centre mark hole are used as practical magnifying power, are calculated according to ideal magnifying power each The undistorted coordinate of index aperture geometric center, to obtain each index aperture geometric center distortion coordinate and undistorted coordinate it Between functional relation, obtain distortion function model.

Preferably, in step S43, distortion function model is second order or fourth order polynomial, passes through each label pore geometry Functional relation between the distortion coordinate at center and undistorted coordinate indicates.

Preferably, in step S43, the distortion function model is second order polynomial distortion function model:

U=a0+a1x+a2y+a3x2+a4y2+a5Xy,

V=b0+b1x+b2y+b3x2+b4y2+b5xy

Wherein, a0 a1 a2 a3 a4 a5And b0 b1 b2 b3 b4 b5It is the coefficient of corresponding polynomial function.(u, v) is ball The CCD coordinates containing distortion of waffle slab index aperture geometric center are preced with, (x, y) is the undistorted seat of spherical crown waffle slab index aperture geometric center Mark.

The beneficial effects of the present invention are:The present invention by the way that independent waffle slab is arranged, be imaged in interferometry The calibration of distortion, by simple structure, can be realized in interferometry in the case where not destroying the measured optical unit surface The advantageous effect of image deformation in situ detection.

Description of the drawings

Fig. 1 is the structure chart of the calibration system of image deformation in interferometry provided by the invention;

Fig. 2 is the structure chart of spherical crown waffle slab in the calibration system of image deformation in interferometry of the present invention;

Fig. 3 is the flow chart of the scaling method of image deformation in interferometry provided by the invention.

Icon explanation:

1, interferometric measuring means 2, spherical crown waffle slab

3, optical element 4, adjustment mechanism are detected

41, the dimension of turntable 42, five adjustment platform

Specific implementation mode

In order to make the purpose , technical scheme and advantage of the present invention be clearer, below in conjunction with attached drawing and specific implementation Example, the present invention will be described in further detail.It should be appreciated that specific embodiment described herein is only explaining this hair It is bright, but not to limit the present invention.

It is real the technical problem to be solved by the present invention is to how under the premise of not destroying tested optical element surface The scaling method of image deformation in a kind of existing interferometry simple in structure, accuracy of detection is high.

It is independent firstly the need of making before being demarcated in the interferometry of the present invention in the calibration system of image deformation Waffle slab.Wherein, waffle slab is the thin spherical cap structure for being evenly distributed with calibration hole thereon, and spherical crown waffle slab is according to tested optics The parameter designings such as the radius of curvature of element and bore form.Since in calibration, thin spherical crown waffle slab will be with tested optical element Detected intimate surface contact, therefore, the surface curvature radius that thin spherical crown waffle slab is contacted with tested optical element need to be with quilts It is identical to examine optical element radius of curvature.Equally distributed index aperture distribution is that can cover tested light on thin spherical crown waffle slab The tested region of element is learned, while also making has X-axis and Y-axis, the X-axis and Y-axis of thin spherical crown waffle slab on thin spherical crown waffle slab It is indicated by the way that the specific markers hole of change in coordinate axis direction can be identified.

Fig. 1 is the structure chart of the calibration system of image deformation in interferometry of the present invention.It specifically includes:Interferometric measuring means 1, adjustment mechanism 4, spherical crown waffle slab 2 and data processing equipment 5.

Reference axis made of being evenly distributed with index aperture on spherical crown waffle slab 2 and being marked by the index aperture, spherical crown grid The radius of curvature of plate 2 is identical as to tested 3 radius of curvature of optical element, for being demarcated into line distortion to tested optical element 3.

Adjustment mechanism 4 is in 1 confocal interference test position of interferometric measuring means for adjusting the tested optical element 3 of optics, Tested optical element 3 is detected the optical axis coincidence of regional center, the geometric center and the interferometric measuring means 1 of spherical crown waffle slab 2, And adjust the reference axis of spherical crown waffle slab 2 and the ccd detector coordinate overlapping of axles of interferometric measuring means 1.3 quilt of tested optical element Inspection region is its effective coverage.

Interferometric measuring means 1 obtain spherical crown net for carrying out interference detection to spherical crown waffle slab 2 and tested optical element 3 The interference pattern of the interference pattern and tested optical element 3 of 2 index aperture of panel.

Data processing equipment 5, for calculating distortion coordinate according to the interference diagram data of 2 index aperture of spherical crown waffle slab and without abnormal The relationship for becoming coordinate, obtains distortion function;It is additionally operable to, according to the interference pattern and distortion function that are detected optical element 3, be calculated The face shape error of tested optical element 3, to complete the calibration of image deformation in interferometry.

Interferometric measuring means 1 are oppositely arranged with adjustment mechanism 4, and tested optical element 3 is set on adjustment mechanism 4, spherical crown Waffle slab 2 is set between interferometric measuring means 1 and tested optical element 3, and spherical crown waffle slab 2 is removably detected light with optics Learn the contact of 3 surface of element.

In one particular embodiment of the present invention, interferometric measuring means 1 be commercial lasers interferometer 1, adjustment mechanism 4 by Turntable 41 and with five dimension adjustment platforms 42 constitute, five dimension adjustment platforms 42 can around and move upwards.As shown in Fig. 2, spherical crown Waffle slab 2 will be with 3 intimate surface contact of tested optical element, therefore the surface that spherical crown waffle slab 2 is contacted with tested optical element 3 is bent Rate radius R need to be identical as 3 radius of curvature of tested optical element, spherical crown waffle slab 2 and 3 discontiguous surface R ' of tested optical element Concentric circles is formed with R.Spherical crown waffle slab 2 is to be formed using what metal or other light-proof materials made, carries uniformly divide thereon Cloth index aperture, the whole that equally distributed index aperture distribution covering is detected optical element 3 are detected region, while in X-axis and Y The index aperture of change in coordinate axis direction can be identified by being made on axis.It is spherical mirror, spherical crown waffle slab that optical element 3 is detected in the present embodiment 2 be also curved-surface structure, and in order to make index aperture preferably light transmission, therefore, index aperture in the present embodiment is conical through-hole, and taper The direction that through-hole radially reduces is close to tested 3 side of optical element.

Specific work process is:First position and the lateral attitude that the adjustment of platform 42 is detected optical element 3 are adjusted by five dimensions It is at the confocal interference test position of interferometric measuring means 1, tested optical element 3 is made by the focusing of interferometric measuring means 1 It being capable of blur-free imaging on the ccd detector of interferometric measuring means 1.Then, it adjusts the adjustment of platform 5 by five dimensions and is detected optical element 3 spatial position makes its tested regional center and 1 optical axis coincidence of interferometric measuring means.

Spherical crown waffle slab 2 is installed on tested optical element 2, specifically, spherical crown waffle slab 2 further includes fixed mechanism, For fixing spherical crown waffle slab 2, in the present embodiment, the fixed structure of spherical crown waffle slab 2 can be removably by spherical crown net Panel 2 is fixed on the frame of tested optical element 3.Adjusting-fixing structure so that spherical crown waffle slab 2 and tested optical element 3 Surface contact or interval 0.1mm or so cause to damage to avoid spherical crown waffle slab 2 to tested 3 surface of optical element;By adjusting Turntable 41 makes the optical axis coincidence of the geometric center of spherical crown waffle slab 2 and interferometric measuring means 1 (due to the hair of interferometric measuring means 1 The light gone out is irradiated on spherical crown waffle slab 2, and is circular pattern, therefore will be on the center of the circular pattern, with spherical crown waffle slab 2 Index aperture alignment positioned at center may make the optical axis weight of the geometric center and interferometric measuring means 1 of spherical crown waffle slab 2 Close), and the reference axis (X-axis, Y-axis) of 2 index aperture of spherical crown waffle slab is made by the angle of the adjustment spherical crown of turntable 4 waffle slab 2 and is done The reference axis (X-axis, Y-axis) related on the ccd detector of measuring device 1 overlaps.

Interferometric measuring means 1 carry out interference detection to spherical crown waffle slab 2 and tested optical element 3, are detected optics member at this time Part 3 and spherical crown waffle slab 2 are imaged on the ccd detector of interferometric measuring means 1 simultaneously, since spherical crown waffle slab 2 is opaque Material is made, therefore only there are interference patterns for the label of spherical crown waffle slab 2 bore region, therefore CCD will only show several The interference pattern for the index aperture that is spacedly distributed.

The multiframe phase shift of the ccd detector output of interferometric measuring means 1 during the extraction interferometry of data processing equipment 5 Interfere diagram data, and large change, rather than the light intensity of label bore region are will produce per frame interference pattern light intensity using label bore region The noise spot of substantially stationary feature removal CCD interference patterns.By the arithmetic average for calculating each index aperture whole pixel coordinate Value, acquires the Geometric center coordinates (u of index aperturei,vi), which just represents the CCD coordinate positions in respective markers hole, to obtain Obtain the CCD coordinates containing distortion (u, v) of 2 each index aperture geometric center of spherical crown waffle slab.Data processing equipment 5 extracts spherical crown grid 2 centre mark hole of plate and the mean pixel interval of adjacent four index apertures are used as ideal magnifying power, and by all index apertures in The unit pixel interval of heart index aperture is used as practical magnifying power.Therefore, the practical magnifying power of each index aperture and ideal magnifying power Difference be the label hole site image deformation, obtain distortion coordinate and undistorted coordinate between functional relation, namely Distortion function.

Spherical crown waffle slab 2 is removed, interferometric measuring means 1 carry out interference detection again, and optical element 3 is detected to obtain Interference pattern, data processing equipment 5 calculates according to the interference pattern of tested optical element 3 and the distortion function being calculated before The face shape error of tested optical element 3 is obtained, to complete the image deformation calibration during interferometry.

Corresponding to the calibration system of image deformation in the interferometry in the present invention, the invention also includes a kind of present invention is dry Relate to the scaling method of image deformation in measuring.Referring to Fig. 3, showing the scaling method of image deformation in interferometry of the present invention The flow chart of one specific embodiment.

When being demarcated, step S1 is executed, tested optical element is adjusted first and is in the confocal dry of interferometric measuring means Test position is related to, tested optical element surface blur-free imaging on ccd detector is made by focusing, then by adjusting tested light The spatial position for learning element makes tested optical element be detected the optical axis coincidence of regional center and interferometric measuring means.Specifically, lead to It crosses and adjusts the adjustment mechanism that platforms form by turntable and five dimensions to adjust tested optical element and spherical crown waffle slab.

Step S2 is executed, spherical crown waffle slab is positioned between interferometric measuring means and tested optical element, and make spherical crown Waffle slab is in close contact with tested optical element surface, can also make spherical crown waffle slab and tested optical element surface interval 0.1mm The distance of left and right causes to damage to avoid spherical crown waffle slab to tested optical element surface.Adjust spherical crown waffle slab index aperture The optical axis coincidence of geometric center and interferometric measuring means, the X-axis of spherical crown waffle slab, Y-axis respectively with interferometric measuring means CCD detection X-axis, the Y-axis of device overlap.

Step S3 is executed, interference detection is carried out using interferometric measuring means, is detected optical element and spherical crown waffle slab simultaneously It is imaged on the ccd detector of interferometric measuring means.Since spherical crown waffle slab is the impermeable photo structure with index aperture, only With the presence of the label bore region interference pattern of spherical crown waffle slab, therefore it will only show that several are spacedly distributed on ccd detector The interference pattern of index aperture.

Step S4 is executed, according to the multiframe exported in the ccd detector of the interferometric measuring means during interferometry The phase shift diagram data of interference containing distortion, and data processing is carried out, obtain distortion polynomial function model.

Specifically, step S4 is further comprising the steps of:S41, spherical crown waffle slab label the bore region interference pattern containing distortion per frame Light intensity will produce large change, rather than mark the light intensity of bore region substantially stationary, is removed according to this feature and is done on ccd detector Relate to the noise spot of figure;S42, the arithmetic mean of instantaneous value by calculating each index aperture whole pixel coordinate of spherical crown waffle slab, acquire ball Geometric center coordinates of each index aperture of waffle slab containing distortion are preced with, the CCD which just represents respective markers hole is sat The CCD coordinates containing distortion (u, v) of cursor position namely each index aperture geometric center of spherical crown waffle slab.

S43, amplified using spherical crown waffle slab centre mark hole and the mean pixel interval of adjacent four index apertures as ideal Rate, using the unit pixel interval in each index aperture and centre mark hole as practical magnifying power.The practical amplification of each index aperture Rate and the difference of ideal magnifying power are the image deformation of the label hole site.Each label can be calculated according to ideal magnifying power The ideal coordinates at pore geometry center, i.e., undistorted coordinate (x, y).Functional relation between distortion coordinate and undistorted coordinate passes through Second order or fourth order polynomial description.Second order polynomial distortion function model is given in the present embodiment:

U=a0+a1x+a2y+a3x2+a4y2+a5Xy,

V=b0+b1x+b2y+b3x2+b4y2+b5xy

Wherein, a0 a1 a2 a3 a4 a5And b0 b1 b2 b3 b4 b5It is the coefficient of corresponding polynomial function.(u, v) is ball The CCD coordinates containing distortion of waffle slab index aperture geometric center are preced with, (x, y) is the undistorted seat of spherical crown waffle slab index aperture geometric center Mark.

It is using what the method that least square fitting method solves multinomial coefficient solved above-mentioned multinomial distortion function model Number a and b, so that it is determined that distortion function, specific solution procedure are:

It enables, u=Ω a, v=Ω b

Wherein, a=[a0 a1 a2 a3 a4 a5]T, u=[u1 u2 u3 … un]T,

B=[b0 b1 b2 b3 b4 b5]T, v=[v1 v2 v3 … vn]T,

unFor the CCD abscissas containing distortion of n-th of waffle slab index aperture geometric center, vn is n-th of waffle slab index aperture The CCD ordinates containing distortion of geometric center, n is positive integer.

A=(ΩTΩ)-1ΩTU=Ω+U, b=(ΩTΩ)-1ΩTV=Ω+v

Wherein, Ω+It is the generalized inverse of Ω.

Step S5 is executed, the spherical crown waffle slab is removed, using the interferometric measuring means to the tested optics member Part carries out interferometry, obtains tested optical element interference pattern containing distortion;

Step S6 is executed, the interference pattern containing distortion using the distortion function model and the tested optical element solves institute The undistorted interference pattern of tested optical element is stated, it is complete to obtain the face shape error in the tested optical element distortion interference pattern The distortion calibration of the pairs of tested optical element.

The present invention can not destroyed by the way that independent waffle slab is arranged to carry out the calibration of image deformation in interferometry In the case of the measured optical unit surface, by simple structure, image deformation in situ detection is beneficial in realization interferometry Effect.

The specific implementation mode of present invention described above, is not intended to limit the scope of the present invention..Any basis Various other corresponding changes made by the technical concept of the present invention and deformation, should be included in the guarantor of the claims in the present invention It protects in range.

Claims (10)

1. the calibration system of image deformation in a kind of interferometry, including interferometric measuring means, adjustment mechanism, which is characterized in that Further include spherical crown waffle slab and data processing equipment;
Reference axis made of index aperture is distributed on the spherical crown waffle slab and is marked by the index aperture, the spherical crown grid The radius of curvature of plate is identical as to tested optical element radius of curvature, for being demarcated into line distortion to the tested optical element;
The adjustment mechanism is in interferometric measuring means confocal interference detection for adjusting the tested optical element of the optics Position, the tested optical element are detected regional center, the geometric center of the spherical crown waffle slab and the interferometric measuring means Optical axis coincidence, and adjust the reference axis weight of the reference axis and the interferometric measuring means ccd detector of the spherical crown waffle slab It closes;
The interferometric measuring means are obtained for carrying out interference detection to the spherical crown waffle slab and the tested optical element The interference pattern of the interference pattern of the spherical crown waffle slab index aperture and the tested optical element;
The data processing equipment, for calculating distortion coordinate and nothing according to the interference diagram data of the spherical crown waffle slab index aperture The functional relation of distortion coordinate, obtains distortion function model;It is additionally operable to according to the interference pattern of the tested optical element and described The face shape error of the tested optical element is calculated in distortion function model;
The interferometric measuring means are oppositely arranged with the adjustment mechanism, and the tested optical element is set to the adjustment mechanism On, the spherical crown waffle slab is set between the interferometric measuring means and the tested optical element.
2. the calibration system of image deformation in interferometry as described in claim 1, which is characterized in that the spherical crown waffle slab For metal structure, the index aperture is conical through-hole.
3. the calibration system of image deformation in interferometry as described in claim 1, which is characterized in that the adjustment structure packet Turntable and five dimension adjustment platforms are included, the turntable is set on the five dimensions adjustment platform;
The five dimensions adjustment platform is used to adjust the spatial position of the tested optical element, makes the tested optical element and described Spherical crown waffle slab is detected regional center and the interferometric measuring means optical axis coincidence;
The turntable is used to adjust the optical axis coincidence of the geometric center and the interferometric measuring means of the spherical crown waffle slab.
4. the calibration system of image deformation in interferometry as described in claim 1, which is characterized in that the spherical crown waffle slab Further include fixed structure, for the spherical crown waffle slab to be fixed on the tested optical element.
5. the calibration system of image deformation in interferometry as described in claim 1, which is characterized in that the interferometry dress The mean pixel interval of extraction spherical crown waffle slab centre mark hole and adjacent four index apertures is set as ideal magnifying power, and by institute There are index aperture and the unit pixel interval in centre mark hole to be used as practical magnifying power, according to the spherical crown waffle slab index aperture containing abnormal Become interference diagram data, calculates the functional relation between the spherical crown waffle slab index aperture distortion coordinate and undistorted coordinate, obtain Distortion function model.
6. the scaling method of image deformation in a kind of interferometry, which is characterized in that include the following steps:
S1, adjustment are detected optical element and are in the confocal interference test position of interferometric measuring means, and make the tested optics member Part surface blur-free imaging on ccd detector adjusts the tested optical element and is detected regional center and interferometry dress Set optical axis coincidence;
S2, spherical crown waffle slab is positioned between the interferometric measuring means and the tested optical element, the spherical crown grid Plate side is contacted with the tested optical element surface, adjusts the geometric center of the waffle slab index aperture and the interferometry Device optical axis coincidence, and make the reference axis of the spherical crown waffle slab index aperture respectively with the interferometric measuring means ccd detector Coordinate overlapping of axles;The spherical crown waffle slab is formed according to the radius of curvature and bore parameter designing of tested optical element, described Spherical crown waffle slab is the impermeable photo structure with index aperture and reference axis;
S3, interference detection is carried out to the spherical crown waffle slab and the tested optical element using the interferometric measuring means, obtained Take the interference pattern containing distortion of the spherical crown waffle slab index aperture;
S4, according to the spherical crown waffle slab index aperture containing distortion interference diagram data, and extract spherical crown waffle slab centre mark hole with The mean pixel interval of adjacent four index apertures is as ideal magnifying power, by the unit pixel of all index apertures and centre mark hole Interval is used as practical magnifying power, and the function calculated between the spherical crown waffle slab index aperture distortion coordinate and undistorted coordinate closes System, obtains distortion function model;
S5, the spherical crown waffle slab is removed, interference survey is carried out to the tested optical element using the interferometric measuring means Amount obtains tested optical element interference pattern containing distortion;
S6, the interference pattern containing distortion using the distortion function model and the tested optical element solve the tested optics member Part is undistorted, and interference pattern is completed to obtain the face shape error in the tested optical element distortion interference pattern to described tested The distortion of optical element is demarcated.
7. the scaling method of image deformation in interferometry as claimed in claim 6, which is characterized in that in the step S2, The surface curvature radius that the spherical crown waffle slab is contacted with the tested optical element is identical as tested optical element radius of curvature, The index aperture of change in coordinate axis direction can be identified by being made in X-axis and Y-axis simultaneously.
8. the scaling method of image deformation in interferometry as claimed in claim 6, which is characterized in that the step S4 includes Following steps:
The noise spot of S41, removal spherical crown waffle slab index aperture interference pattern containing distortion;
S42, the arithmetic mean of instantaneous value by calculating each index aperture whole pixel coordinate of spherical crown waffle slab, it is every to acquire spherical crown waffle slab Geometric center coordinates of a index aperture containing distortion;
S43, using the mean pixel interval of spherical crown waffle slab centre mark hole and adjacent four index apertures as ideal magnifying power, often A index aperture and the unit pixel interval in centre mark hole are used as practical magnifying power, and each index aperture is calculated according to ideal magnifying power The undistorted coordinate of geometric center, to obtain the letter between the distortion coordinate of each index aperture geometric center and undistorted coordinate Number relationship, obtains distortion function model.
9. the scaling method of image deformation in interferometry as claimed in claim 8, which is characterized in that in step S43, distortion Function model is second order or fourth order polynomial, by between the distortion coordinate and undistorted coordinate of each index aperture geometric center Functional relation indicates.
10. the scaling method of image deformation in interferometry as claimed in claim 9, which is characterized in that in step S43, institute It is second order polynomial distortion function model to state distortion function model:
U=a0+a1x+a2y+a3x2+a4y2+a5Xy,
V=b0+b1x+b2y+b3x2+b4y2+b5xy
Wherein, a0a1a2a3a4a5And b0b1b2b3b4b5It is the coefficient of corresponding polynomial function, (u, v) is spherical crown waffle slab index aperture The CCD coordinates containing distortion of geometric center, (x, y) are the undistorted coordinate of spherical crown waffle slab index aperture geometric center.
CN201510962490.8A 2015-12-21 2015-12-21 The calibration system and scaling method of image deformation in a kind of interferometry CN106247972B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201510962490.8A CN106247972B (en) 2015-12-21 2015-12-21 The calibration system and scaling method of image deformation in a kind of interferometry

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201510962490.8A CN106247972B (en) 2015-12-21 2015-12-21 The calibration system and scaling method of image deformation in a kind of interferometry

Publications (2)

Publication Number Publication Date
CN106247972A CN106247972A (en) 2016-12-21
CN106247972B true CN106247972B (en) 2018-09-21

Family

ID=57626781

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201510962490.8A CN106247972B (en) 2015-12-21 2015-12-21 The calibration system and scaling method of image deformation in a kind of interferometry

Country Status (1)

Country Link
CN (1) CN106247972B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109931874A (en) * 2019-04-04 2019-06-25 北京理工大学 Ball-type inertance element fit clearance laser differential confocal precision measurement method

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1227635A (en) * 1996-08-06 1999-09-01 康斯坦丁·罗格兹 Holographic system for large image production
CN101033937A (en) * 2007-04-13 2007-09-12 南京师范大学 Method and device of light splitting, image-forming and synchronous phase-shifting in optical interferometry.
CN102540751A (en) * 2010-12-28 2012-07-04 上海微电子装备有限公司 Method for detecting distortion and curvature of field of projection objective
CN103136756A (en) * 2013-03-04 2013-06-05 江苏大学 Demarcated target for demarcating cameras with different accurate degrees and demarcating method thereof
CN103267629A (en) * 2013-06-25 2013-08-28 中国科学院上海光学精密机械研究所 Point-diffraction interference wave aberration measuring instrument
CN104006759A (en) * 2014-05-05 2014-08-27 中国科学院长春光学精密机械与物理研究所 Composite detection method for large-diameter non-spherical reflector with large deviation in polishing process
CN104181780A (en) * 2014-09-16 2014-12-03 中国科学院光电技术研究所 Aberration compensation device and aberration compensation method of optical system

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1227635A (en) * 1996-08-06 1999-09-01 康斯坦丁·罗格兹 Holographic system for large image production
CN101033937A (en) * 2007-04-13 2007-09-12 南京师范大学 Method and device of light splitting, image-forming and synchronous phase-shifting in optical interferometry.
CN102540751A (en) * 2010-12-28 2012-07-04 上海微电子装备有限公司 Method for detecting distortion and curvature of field of projection objective
CN103136756A (en) * 2013-03-04 2013-06-05 江苏大学 Demarcated target for demarcating cameras with different accurate degrees and demarcating method thereof
CN103267629A (en) * 2013-06-25 2013-08-28 中国科学院上海光学精密机械研究所 Point-diffraction interference wave aberration measuring instrument
CN104006759A (en) * 2014-05-05 2014-08-27 中国科学院长春光学精密机械与物理研究所 Composite detection method for large-diameter non-spherical reflector with large deviation in polishing process
CN104181780A (en) * 2014-09-16 2014-12-03 中国科学院光电技术研究所 Aberration compensation device and aberration compensation method of optical system

Also Published As

Publication number Publication date
CN106247972A (en) 2016-12-21

Similar Documents

Publication Publication Date Title
JP6491677B2 (en) Computational wafer inspection
TWI628696B (en) Process window optimizer
TWI616642B (en) Metrology method and apparatus for measuring a parameter of a lithographic process, computer program and lithographic system
KR101467924B1 (en) Inspecting apparatus and inspecting method
KR100673487B1 (en) Reticle and optical characteristic measuring method
TWI417640B (en) A camera lens calibration system
KR100863027B1 (en) Lithographic process monitoring and system basis of electoron beam imaging
EP1063570B1 (en) In situ projection optic metrology method and apparatus
Soloff et al. Distortion compensation for generalized stereoscopic particle image velocimetry
CN105684127A (en) Differential methods and apparatus for metrology of semiconductor targets
EP1631809B1 (en) Method for determining the image quality of an optical imaging system
US8773652B2 (en) Method and device for aligning a lens with an optical system
EP1618426B1 (en) Method and array for determining the focal position during imaging of a sample
US7518110B2 (en) Pattern measuring method and pattern measuring device
JP6346296B2 (en) Metrology method and apparatus, substrate, lithography system and device manufacturing method
TWI616721B (en) Critical dimension uniformity monitoring for extreme ultra-violet reticles
KR101994385B1 (en) Method of measuring asymmetry, inspection apparatus, lithographic system and device manufacturing method
KR20140115256A (en) Inspection method
JP4898766B2 (en) Method and system for measuring the position of an object
KR20200045577A (en) Inspecting a wafer and/or predicting one or more characteristics of a device being formed on a wafer
JP2008275612A (en) Device equipped with high resolution measurement structure on substrate for manufacturing semiconductor, and use of aperture in measuring device
CN102661956B (en) Super-smooth surface defect detection system and distortion correction method thereof
JP5793093B2 (en) Inspection apparatus and inspection method
US20030038933A1 (en) Calibration apparatus, system and method
US20130194569A1 (en) Substrate inspection method

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant