TW394854B - Method for testing an optical lens module - Google Patents

Abstract

A method for testing an optical lens module, which passes the rays through a raster and a lens module to be tested and projects onto an image capture device. During test, the lens module is moved such that the image is formed on the image capture device, and then rotates the lens module by using a determined evaluation function to find out the best rotation angle for the lens module, rotates the lens module to the best rotation angle and then gradually move the foregoing lens module and at the same time calculate the corresponding modulation transformation function value until such modulation transformation function value is of the highest level, and that is the best position to generate the image for the lens module. Then, calculate the quality parameter corresponding to the foregoing best rotation angle and the best position, and finally check if it falls within the error allowance range of the specification for determining the quality of the lens module.

Description

5. Description of the invention (1) The present invention relates to an optical lens group detection method with more accurate detection. Please refer to Fig. 1. Fig. 1 is a schematic diagram showing the components of a conventional scanner. The manuscript 11 is placed on the glass 12 'The light source 13 emits a line through the glass ^ 12' The manuscript 1 1, the reflection mirror 4 (actually, there is more than one reflection mirror, but a reflection path is formed by several pieces), then The image is displayed on the charge-coupled device (CCD) 16 through the lens group 5 and finally the corresponding signal is output by the charge-coupled device 16 to return the original content. Among them, the light source 3, the mirror 14, the lens group 15, and the charge coupled device (CCD) 16 are all arranged in the same scanning module, so the above components can be moved synchronously to maintain a fixed object / image distance. In the mass production of the above-mentioned lens group 15, due to manufacturing tolerances and other problems, the center line of each lens in the lens group may not be aligned, which will cause problems such as phase differences. Therefore, it is necessary to use a testing device to perform quality control to eliminate defective products. Lens group. Patent No. 86220888 (in application) of the Republic of China provides an optical lens group detection device, please refer to FIG. 2, which includes a light source 31, a grating 32, a lens group holder 34, a charge-coupled device 35, and a computer 36. 15 is the lens group to be tested. The light source 31 of this device can emit light that is reflected by the grating 32, and then received by the charge-coupled device 35 through the lens group 15, and then the computer 36 calculates the quality parameters of the lens group (modulation conversion function Mτρ value and magnification). When testing, first move the lens group 15 up and down to focus accurately, then gradually rotate the lens group 15 to find the maximum MTF, and then fix the lens group 15 to the corresponding angle (that is, the optimal angle). ) And count 'calculate

V. Explanation of the invention (2) The rate is to judge whether it is within the tolerance of the specification, and the quality of the lens group. The detection method described above is to first focus the lens group 15 accurately, and then to find out the optimal rotation angle of ^ _, and the inventor of the present invention found that, in the spin, Goniuyin 'often changes The variation of the MTF value of the conversion function is not large. In other words, ^ Ϊ or other measurement errors will play a significant role in determining the maximum MTF value, so that the rotation angle corresponding to the measured MTF maximum value may not be a positive angle. So unreliable. a. In view of the above-mentioned reasons for the error, the present invention provides a method for detecting a photon lens group, including the following steps: (a) the light is projected to the shadow capture through the grating and the lens group to be measured; (b) The above lens group is roughly imaged on the image capturing device; (C) Turn the above lens group, and use a predetermined evaluation function to find the optimal rotation angle of the lens group, and rotate the lens group to the optimal rotation Angle; U) stepwise move the lens group while calculating the corresponding modulation conversion function value, and use a hierarchical method to find the highest level of the modulation conversion function value, and use the position of the lens group corresponding to the highest level as the lens composition image (E) Calculate the quality parameters of the lens group corresponding to the above-mentioned optimal rotation angle and best position, and then determine whether it is within the tolerance range of the rule. Determine the quality of the lens group. The method of the present invention is changed to find the optimal rotation angle of the lens group (step

Surface C: \ ProgramFiles \ Patent \ 0535-3766-E.ptd page 5 5. Description of the invention (3) = accurate imaging of the lens group (step ⑷), and before finding the mt degree of step c, the present invention only allows the lens The group is roughly imaged. Before finding the optimal rotation angle of the lens group, ϊίΐίί '. Therefore, when the lens group is rotated, the conversion function is adjusted, and the difference will be increased by A, so that the effect of noise or other measurement errors is reduced. It is small, so reliable detection results can be obtained. In order to make the above-mentioned objects, features, and advantages of the present invention more obvious and easier, hereinafter, preferred embodiments are described in detail with reference to the accompanying drawings. Brief description of the drawings: Figure 1 is a schematic diagram of the component configuration of a conventional scanner; Figure 2 is a schematic diagram of a reflective optical lens group detection device; Figure 3 is a schematic diagram of a penetrating optical lens group detection device; Section 4A FIG. 4B is a detection pattern used to detect a 300 dp i lens group in a preferred embodiment of the present invention; FIG. 4B is a detection pattern used to detect a 600 dpi i lens group in a preferred embodiment of the present invention; FIG. 5 is a flowchart of the optical lens group detection method of the present invention; Table 1 shows that a 300 dpi lens group is relative to 45. MTF grading standard for 100 lppi grating; Table 2 shows 600 dpi lens group relative to 8. / 90. MTF classification standard of 150 lppi grating; Table 3 is an example of the MTF classification standard of 300 dpi lens group. Reference number: 11 manuscripts 12 glass

C: \ Program Files \ Patent \ 〇535-3766-E.ptd page 6 V. Description of the invention (4) 13 light source 15 lens group 21 light source 24 26 32 35 14 reflector 1 6 charge-coupled device 2 2 grating lens group Bearing computer grating 25 Charge-coupled device 31 Light source 3 4 Lens group Charge-coupled device 36 6 Computers 41 to 49 The area is illustrated with drawings to illustrate a preferred embodiment of the present invention. The present invention can use the hardware equipment shown in Fig. 2 or Fig. 3, in which the lens group 15 to be tested is mounted on the lens group holders 24 and 34 to move or rotate. Figure 2 shows a reflective detection device. The light source 21 and the lens group 5 are arranged on the same side of the grating 22. The light emitted by the light source 21 is reflected by the grating 22, and then received by the charge coupling device 25 through the lens group 15. The computer 26 calculates the quality parameters (modulation conversion function MTF value and magnification) of the lens group; FIG. 3 shows a transmission detection device, in which the light source 31 and the lens group 15 are respectively disposed on two sides of the grating 32, and the light source The light emitted by 31 passes through the grating 32, and is then received by the charge coupled device 35 through the lens group 15, and the computer 36 calculates the quality parameters of the lens group. Please refer to FIGS. 4A and 4B, which show examples of the detection patterns (ie, the aforementioned gratings 22 and 32) used in the present invention. Among them, FIG. 4A is a detection pattern used to detect a 300 dp i lens group. The middle 4 2 and the right 43 are 45 ° oblique stripes (hereafter used L45, C45, R45 to

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5. Description of the invention (indicated by (5)) 'and the pattern contains 100 line pairs (100 lppi) per inch of width; Figure 4B is the detection pattern used to detect the 600 dpi lens group. Each 0 inch width contains 150 line pairs (1 501 ppi), and the pattern is divided into six regions 'wherein' the left side of the pattern includes regions 44, 45, and region 44 is 90. The vertical stripes (represented by L 9 0 at the bottom), while the area 4 5 is 8. Oblique stripe (represented by L8 at the bottom), the middle of the pattern contains regions 46, 47, region 46 is an 8-stripe stripe (represented by C8 at the bottom), and region 47 is 90. Vertical stripes (represented by C90 at the bottom), the right side of the pattern contains area 48, 49 ', area 48 is 8. The diagonal stripe (represented by R8 at the bottom), while the area 4 9 is a 90 ° vertical stripe (represented by R90 at the bottom). FIG. 5 is a flowchart of the optical lens group detection method of the present invention, and from this process, it can be determined whether the lens group is a good product: Step 1 0 0 ′ The program starts. In step 110, when the adjustment procedure starts and starts, the lens group 15 is moved upward (or downward) a distance 'to intentionally move the lens group 15 away from the imaging position. Step 1 2 G, move the lens group 丨 5 down (up) back to a small distance, and calculate the lens group 15 corresponding to the left / middle / right image of the pattern (ie, the gratings 22 and 32) by the computers 26 and 36. Modulation transfer function (MTF) value. Step 1 3 0 'Computer 2 6 and 3 6 determine whether the mtf values of the left / middle / right three have reached level 1 or higher (refer to the grading table shown in Table 1 and Table 2). If the 4! TF values are all If it has reached the i-th level or higher, step 4o is performed, and if any of the MTF values does not reach the first level or higher, you must return to step 1 to continue the coarse adjustment.

C: \ ProgramFiles \ Patent \ 0535-3766-E_ptd page 8 5. Description of the invention (6)

Table 1: MTF classification standard level of a 300 dpi lens group with respect to a 45 °, 100 lppi grating L45 C45 R45 0 0 0 0 1 20 20 20 2 35 35 35 3 50 50 50 4 55 55 55 5 57 57 57- ^ 6 59 59 59 7 61 61 61 8 63 63 63 9 65 65 65 10 67 67 67 11 69 69 69 12 71 71 71 13 73 73 73 14 75 75 75 15 77 77 77 16 79 79 79 17 81 81 81 18 83 83 83 19 85 85 85 mmu \ C: \ ProgramFiles \ Pateirt \ 0535-3766-E.ptd page 9 5. Description of the invention (7) Table 2: 60 0 dpi lens group relative to 8 ° / 90 °, 150 MTF classification standard grade of lppi grating L90 L8 C8 C90 R8 R90 0 0 0 0 0 0 0 1 20 20 20 20 20 2 35 35 35 35 35 35 3 50 50 50 50 50 50 4 55 55 55 55 55 55 5 57 57 57 57 57 57 6 59 59 59 59 59 59 7 61 61 61 61 61 61 8 63 63 63 63 63 63 9 65 65 65 65 65 65 10 67 67 67 67 67 11 69 69 69 69 69 69 12 71 71 71 71 71 71 13 73 73 73 73 73 73 14 75 75 75 75 75 75 15 77 77 77 77 77 77 16 79 79 79 79 79 79 17 81 81 81 81 81 81 18 83 83 83 83 83 83 19 85 85 85 85 85 85 C: \ ProgramFiles \ Patent \ 0535_3766_E.ptd 10

V. Description of the invention (8) Step 1 4 0 ′ The lens group 15 stops moving up and down and starts rotating at 0. -180. In the range of 'rotate a small angle each time, and the computer 26, 36 calculate the MTF value corresponding to each rotation angle, and then substitute the evaluation function shown in the following formula (1), (2) to find out Among them, the optimal angle (the smaller the evaluation function is, the better the rotation angle corresponding to the minimum value of the evaluation function is the maximum angle), and then the lens group 15 is rotated to this optimal angle. For 30 0 dpi, the evaluation function is [(MTFL45-MTFAVG) 2 + (MTFC45-MTFAVG) 2 + (MTFR45-MTFAVG) 2] X 2 ........ (1) where mtfavg = (mtfL45 + mtfC45 + mtfR45) / 3 For 600 dpi, the evaluation function is ((MTFL90-MTFAVG) 2 + (MTFL8-MTFAVG) 2 + (MTFC90-MTFAVG) 2+ (MTFC8-MTFavg) 2 + (MTFR90-MTFavg) 2 + (MTFR8-MTFavg) 2] ....... (2) where mtfavg = (mtfL90 + mtfL8 + mtfC90 + mtfC8 + mtf_ + MTFR8) / 6 Step 150, move the lens group 15 up (or down) again ) Move-distance away from the imaging position. Step 16 0, move the lens group 15 down (upward) gradually by a small distance,

C: \ ProgramFiles \ Patent \ 0535-3766-E. Ptd page 11 V. Description of the invention (9) Ϊ 2 / month H36 Calculate the MTF value of the lens group 15 corresponding to the pattern (that is, the thumb 22 and = 1 = 1) Then, find out the highest level of MTF value according to the MTF not listed in Table 1 and Table 2. p Compare the MTF value of this highest level with the specification, and determine whether the eighteen are within the tolerance of the specification. Step 180 of the lens group is completed. The procedure is further explained for now. Steps 110 to 130 are the rough adjustment stages. First move the lens group 15 away from the imaging position (which can be towards the grating 22 (32) or toward the charge). Consumption device 25 (35) to move, just move away from the imaging position), and then gradually move a small distance in the opposite direction, and stop moving when the MTF value reaches level 以上 above, at this time it can be regarded as completing the rough adjustment. The grading methods described in Tables 1 and 2 will vary depending on the situation (such as design concepts and manufacturing methods). The most typical method is to divide the MTF value from 20 to 85 into 20 levels, reaching Level 1. The above means that the Τρ value is greater than 20 ° In step 140, the lens group 1 The range of 5 rotations is between 0.-180. Due to the characteristics of symmetry, 0.-180. and 180. _ 360. The results are symmetrical to each other, so you only need to rotate 1 8 0., you can know 0-3 6 In the case of 0. In step 140, the lens group 15 is rotated within the range of 0.-1 80. 'This is rotated by a small angle at a time' if this small angle is 5. 'Bei, 1 8 0. / 5. = 36 'The lens group must be rotated 36 times to obtain a total of 36 groups of evaluation function values, where the angle corresponding to the minimum value is the best rotation angle. If the small angle is divided, the

C: \ ProgramFiles \ Patent \ 0535-3766-E.ptd Page 12 V. Description of the invention (10) The finer it is, the more groups of evaluation functions will be obtained. 社 社 0 ^ w Accuracy measured by numerical results It will also be higher, but it will also take more time to do the same thing. Let ’s report the difference and evaluation. Therefore, how to divide the small angle is determined by each situation, and there is no step 160. Now one of the 300 dpi lens groups is moved gradually by a small distance, a total of A, B, c, and 0 different imaging positions. The corresponding left / middle / MTF classification results (see Table 丨) are shown in the MTF values in Table 3 and Table 3: Example of the use of MTF classification standards for 300 dpi lens groups. Imaging position ABCDRF Left 80 82 79 73 60 50 VJ Ας. Middle 65 75 79 80 81 78 HO 67 Right 52 60 67 73 76 78 79 Grade 3 6 10 13 6 3 2 Among them, the minimum MTF value of position D is 73, according to Table 1, position]) will be assigned to the first Level 3, the MTF value of the small position E table is 60. According to Table 1, the position ρ will be assigned to the 6th level. Because in the seven different imaging positions of A, B, C, D, E, F, and G, the special level of _. Position D dares to 'so position]] The quality parameters (mtf value and magnification) are required. . In this example, the left / middle / right MTF values are all considered to be equally important 'but in some cases' may be multiplied by weights to adjust the influence of the left / middle / right three.

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It can be known from the above description that the present invention first finds the optimal rotation of the lens group X step 1 40), and then accurately focuses the lens group (step 16 0), and before finding the optimal rotation angle of the lens group The present invention only makes the lens group roughly f image (step 1 30). In other words, the image of the optimal rotation angle of the lens group is not accurately imaged. Therefore, when the lens group is rotated, the variation of the MTF value of the modulation conversion function will be It will increase, so that the influence of noise or other measurement errors is reduced ', so that reliable detection results can be obtained. Although the present invention has been limited to better implementation of the present invention by anyone who is familiar with this technology and scope, it can still be protected slightly. As the attached patent application example is disclosed above, it is not intended for artists. Without departing from the fine motion and retouching of the present invention, the definition of the protection scope of the present invention shall prevail. ,

C: \ ProgramFiles \ Patent \ 0535-3766-E.ptd page 14

Claims (1)

I Jf · Day ---- One cable number S711 double I hair „£ 6. Application for patent scope 1 · An optical lens group detection method 'includes the following steps: (a) Light is projected through the grating and the lens group to be tested To the image capture exhibition, please ask X:. * · Bei Repeated substance (b) Move the lens group to roughly form an image on the captured image; (C) Rotate the lens group and use a predetermined evaluation function to find the optimal rotation angle of the lens group. The lens group is rotated to the optimal rotation angle; (d) the lens group is gradually moved while calculating the corresponding modulation conversion function value 'and using a hierarchical method to find the highest level of the modulation conversion function value' and using the highest The position of the lens group corresponding to the level is the optimal position of the lens composition image. 2 · The method for detecting an optical lens group according to item 1 of the scope of the patent application, after step (d), further includes a step (e) of calculating the quality parameters of the lens group corresponding to the optimal rotation angle and the best position (e ). 3. According to the optical lens group detection method described in item 1 of the scope of the patent application, in step (a), the light is reflected by the grating and then projected to the image capture device through the lens group under test. 4. According to the optical lens group detection method described in item 1 of the patent application scope, in step (a), the light passes through the grating, and then is projected to the image capturing device through the lens group to be tested. 5. The method for detecting an optical lens group according to item 1 of the stated patent scope, wherein the grating includes a plurality of sequentially connected regions, and in step (b), when the lens group is relative to the grating each When the modulation transfer function value of the imaging of a region is greater than a predetermined value, the approximate imaging is completed. 6. The detection method of the optical lens group as described in item 5 of the scope of patent application .pV 1998.09.01-015 I Jf · Day ---- One cable number S711 double I hair „£ 6. Application for patent scope 1 · An optical lens group detection method 'includes the following steps: (a) Light is projected through the grating and the lens group to be tested To the image capture exhibition, please ask X:. * · Bei Repeated substance (b) Move the lens group to roughly form an image on the captured image; (C) Rotate the lens group and use a predetermined evaluation function to find the optimal rotation angle of the lens group. The lens group is rotated to the optimal rotation angle; (d) the lens group is gradually moved while calculating the corresponding modulation conversion function value 'and using a hierarchical method to find the highest level of the modulation conversion function value' and using the highest The position of the lens group corresponding to the level is the optimal position of the lens composition image. 2 · The method for detecting an optical lens group according to item 1 of the scope of the patent application, after step (d), further includes a step (e) of calculating the quality parameters of the lens group corresponding to the optimal rotation angle and the best position (e ). 3. According to the optical lens group detection method described in item 1 of the scope of the patent application, in step (a), the light is reflected by the grating and then projected to the image capture device through the lens group under test. 4. According to the optical lens group detection method described in item 1 of the patent application scope, in step (a), the light passes through the grating, and then is projected to the image capturing device through the lens group to be tested. 5. The method for detecting an optical lens group according to item 1 of the stated patent scope, wherein the grating includes a plurality of sequentially connected regions, and in step (b), when the lens group is relative to the grating each When the modulation transfer function value of the imaging of a region is greater than a predetermined value, the approximate imaging is completed. 6. The detection method of the optical lens group as described in item 5 of the scope of patent application .pV 1998.09.01-015 銮 虢 87113432 6. The scope of patent application method, wherein the grating includes three regions connected in sequence. 7. Detecting the optical lens group as described in item 6 of the scope of the patent application = · 'Wherein, these areas all contain stripes of 100 line pairs / inch, and the established 8. As in the fifth area of the scope of patent application The optical lens group detection method described above, wherein the grating includes six areas sequentially connected. 9. The inspection of the optical lens group as described in item 8 of the scope of the patent application ^ Wherein, these areas contain 150 line pairs / hour of stripes, j ^ established < 10. The optics as described in the scope of patent application item 丨The lens group inspection is in the step (CO, the range of rotation of the lens group is 0-18). In the optical lens group inspection 2 described in item 1 of the patent application scope, 'The 2 grids include n consecutively connected = The evaluation function is your 7 骒 (CN ^ MTF.-MTF ^) in the French law 2 / = 1 where N is a positive integer MTFi is the conversion function of the lens group-relative to the imaging period of the i-th area of the grating Then the minimum value of the value of the evaluation function corresponds to 12. For example, the angle f in the scope of the patent application is the optimal rotation angle., N = Optical lens group detection method through the term R, where n = 3 and N = 2. 13. If you want to use the optical lens group detection method described in item 11 of the patent scope Untitled Page 16! 998. 09. 〇 !. 銮 虢 87113432 6. The scope of patent application method, wherein the grating includes three regions connected in sequence. 7. Detecting the optical lens group as described in item 6 of the scope of the patent application = · 'Wherein, these areas all contain stripes of 100 line pairs / inch, and the established 8. As in the fifth area of the scope of patent application The optical lens group detection method described above, wherein the grating includes six areas sequentially connected. 9. The inspection of the optical lens group as described in item 8 of the scope of the patent application ^ Wherein, these areas contain 150 line pairs / hour of stripes, j ^ established < 10. The optics as described in the scope of patent application item 丨The lens group inspection is in the step (CO, the range of rotation of the lens group is 0-18). In the optical lens group inspection 2 described in item 1 of the patent application scope, 'The 2 grids include n consecutively connected = The evaluation function is your 7 骒 (CN ^ MTF.-MTF ^) in the French law 2 / = 1 where N is a positive integer MTFi is the conversion function of the lens group-relative to the imaging period of the i-th area of the grating Then the minimum value of the value of the evaluation function corresponds to 12. For example, the angle f in the scope of the patent application is the optimal rotation angle., N = Optical lens group detection method through the term R, where n = 3 and N = 2. 13. If you want to use the optical lens group detection method described in item 11 of the patent scope Untitled Page 16! 998. 09. 〇 !. Method, where n = 6 and N = 1. 1, 14. The quality parameter in step (e) of the optical lens group detection method described in item 2 of the scope of the patent application is the modulation conversion function value of the lens group corresponding to the best rotation angle and the best position . 15. A method for detecting an optical lens group, including the following steps: (a) projecting light to an image capture device through a grating and a lens group to be measured; wherein the grating is divided into a plurality of regions to be measured; ^ (b ) Perform a coarse adjustment step, and move the lens group to a position. The value of the plurality of adjustment conversion functions corresponding to the waiting area on the image capture device is greater than a predetermined value, and the lens group is fixed at the position. (C) rotating the lens group at a predetermined angle segment, and calculating a plurality of evaluation function values corresponding to each of the predetermined angle segments, and finding the optimal rotation of the lens group from the evaluation function values The lens group is rotated to the optimal rotation angle; (d) performing a fine adjustment step, gradually moving the lens group by a predetermined position segment, and calculating the modulation conversion of each group corresponding to the predetermined position segment For the function value, the minimum value of the modulation conversion function values of each group is selected to find the maximum value among the minimum values, and the corresponding position of the maximum value is the optimal position of the lens group. 16. The method for detecting an optical lens group as described in Patent Application-Scope Item 15, after step (d), further comprising calculating a quality parameter of the lens group corresponding to the best rotation angle and the best position Step (e). 1 7 · According to the optical lens group detection method described in item 15 of the scope of the patent application, 'in step (a), the light is reflected by the grating' and then passes through the Untitled Page 17 1998.09.01.017 Method, where n = 6 and N = 1. 1, 14. The quality parameter in step (e) of the optical lens group detection method described in item 2 of the scope of the patent application is the modulation conversion function value of the lens group corresponding to the best rotation angle and the best position . 15. A method for detecting an optical lens group, including the following steps: (a) projecting light to an image capture device through a grating and a lens group to be measured; wherein the grating is divided into a plurality of regions to be measured; ^ (b ) Perform a coarse adjustment step, and move the lens group to a position. The value of the plurality of adjustment conversion functions corresponding to the waiting area on the image capture device is greater than a predetermined value, and the lens group is fixed at the position. (C) rotating the lens group at a predetermined angle segment, and calculating a plurality of evaluation function values corresponding to each of the predetermined angle segments, and finding the optimal rotation of the lens group from the evaluation function values The lens group is rotated to the optimal rotation angle; (d) performing a fine adjustment step, gradually moving the lens group by a predetermined position segment, and calculating the modulation conversion of each group corresponding to the predetermined position segment For the function value, the minimum value of the modulation conversion function values of each group is selected to find the maximum value among the minimum values, and the corresponding position of the maximum value is the optimal position of the lens group. 16. The method for detecting an optical lens group as described in Patent Application-Scope Item 15, after step (d), further comprising calculating a quality parameter of the lens group corresponding to the best rotation angle and the best position Step (e). 1 7 · According to the optical lens group detection method described in item 15 of the scope of the patent application, 'in step (a), the light is reflected by the grating' and then passes through the Untitled Page 17 1998. 09 · 01 · 017 _Case No. 871134 Sacrifice 7 cars / day Amendment __ Sixth, the scope of patent application The lens group to be tested is projected to the image capture device. 1 8 · According to the optical lens group detection method described in item 15 of the scope of patent application, in step (a), the light is transmitted through the grating 'and then projected to the image extraction device through the lens group to be measured. 19. According to the optical lens group detection method described in item 15 of the scope of the patent application, in step (a), the waiting area to be measured is n, and in step (c), the evaluation functions are i = \ Where N is a positive integer M TF i is the modulation conversion function avg =, jn of the lens group relative to the i-th area of the grating, and the angle corresponding to the minimum value of the evaluation function is the optimal rotation angle. 2 0. The method for detecting an optical lens group according to item 9 of the application specific range, wherein n = 3 and N = 2. 2 1. The method for detecting an optical lens group according to item 19 of the patent application scope, wherein n = 6 and N = 1. C: \ ProgramFiles \ Patent \ 0535-3766-e.ptc page 18 1998.09.01.018 _Case No. 871134 Siege 7 cars / day correction__16. Patent application scope The lens group under test is projected to the image capture device . 1 8 · According to the optical lens group detection method described in item 15 of the scope of patent application, in step (a), the light is transmitted through the grating 'and then projected to the image extraction device through the lens group to be measured. 19. According to the optical lens group detection method described in item 15 of the scope of the patent application, in step (a), the waiting area to be measured is n, and in step (c), the evaluation functions are i = \ Where N is a positive integer M TF i is the modulation conversion function avg =, jn of the lens group relative to the i-th area of the grating, and the angle corresponding to the minimum value of the evaluation function is the optimal rotation angle. 2 0. The method for detecting an optical lens group according to item 9 of the application specific range, wherein n = 3 and N = 2. 2 1. The method for detecting an optical lens group according to item 19 of the patent application scope, wherein n = 6 and N = 1. C: \ ProgramFiles \ Patent \ 0535-3766-e.ptc page 18 1998.09.01.018