Method for testing aspherical surface shape and testing device for testing aspherical surface shape

Abstract

The application provides a method for detecting aspheric surface shape and a detection device for detecting aspheric surface shape, the method comprising: obtaining an interference light-out structure, a calculated holographic structure, a structure to be detected and an adjusting structure, and roughly aligning the interference light-out structure, the calculated holographic structure, the structure to be detected and the adjusting structure; adjusting the positions of the adjusting structure and the structure to be detected to accurately align the structure to be detected with the interference light-out structure; and detecting the aspheric surface shape of the structure to be detected by the interference light-out structure; wherein the calculated holographic structure is a structure with a calculated hologram. The application solves the problem of large detection error of aspheric surfaces and free-form surfaces in the prior art.

Description

Technical Field

[0001] This invention relates to the field of aspherical surface shape detection equipment, and more specifically, to a method for detecting aspherical surfaces and a detection device for detecting aspherical surfaces. Background Technology

[0002] In the field of optical imaging, off-axis aspherical and freeform surfaces, due to their excellent aberration correction capabilities, play an important role in improving the performance, reducing the weight, and minimizing the size of optical systems. They are widely used in aerospace optical telescopes, near-eye display optical systems, and ultraviolet lithography objectives. However, lenses with off-axis aspherical or freeform surfaces exhibit significant variations in surface shape, which is detrimental to their inspection. Current methods mostly employ coordinate measuring machines (CMMs), Luphscan (3D laser scanning point cloud processing software), and UA3P (3D optical profilometer) for inspection. However, due to the irregularity of aspherical and freeform surfaces, it is difficult to pinpoint their coordinates during inspection, and scanning errors also occur during 3D scanning. Computational hologram detection methods are widely used due to their advantages such as large compensation range, high detection accuracy, and fast detection speed. However, the surface shape error of the detected surface is affected by the lens adjustment posture during the process of using computational hologram detection methods. Therefore, the magnitude of the surface shape error value of the detected surface cannot be determined, resulting in inaccurate detection results for the entire surface shape. In other words, the detection error is relatively large for aspherical and freeform surfaces.

[0003] In other words, existing technologies for aspherical and freeform surfaces suffer from large detection errors. Summary of the Invention

[0004] The main objective of this invention is to provide a method for detecting aspherical surfaces and a detection device for detecting aspherical surfaces, so as to solve the problem of large detection errors in aspherical and free-form surfaces in the prior art.

[0005] To achieve the above objectives, according to one aspect of the present invention, a method for detecting aspherical surface shapes is provided, comprising: acquiring an interference light-emitting structure, a computational holographic structure, a structure to be detected, and an adjustment structure; roughly aligning the interference light-emitting structure, the computational holographic structure, the structure to be detected, and the adjustment structure; adjusting the positions of the adjustment structure and the structure to be detected to precisely align the structure to be detected with the interference light-emitting structure; and detecting the aspherical surface shape of the structure to be detected using the interference light-emitting structure; wherein the computational holographic structure is a structure having a computational hologram.

[0006] Furthermore, the process of roughly aligning the interference light-emitting structure, the computational holographic structure, the structure to be detected, and the adjustment structure includes: aligning the interference light-emitting structure with the computational holographic structure; aligning the adjustment structure with the computational holographic structure, so as to roughly align the structure to be detected with the computational holographic structure.

[0007] Furthermore, the process of aligning the interference light-emitting structure with the computational holographic structure includes: the interference light-emitting structure emitting light rays, and the reflection area of ​​the computational holographic structure reflecting the light rays onto the interference light-emitting structure; adjusting the position of the computational holographic structure until the interference fringes are adjusted to zero fringes, thus completing the alignment of the computational holographic structure with the interference light-emitting structure; wherein the computational holographic structure is configured to have a first region for light transmission, a reflection region for light reflection, and an alignment region for light transmission.

[0008] Furthermore, the process of aligning the adjustment structure with the computational holographic structure to achieve a rough alignment between the structure to be detected and the computational holographic structure includes: the interference light-emitting structure emitting light rays, the alignment area of ​​the computational holographic structure transmitting light rays, and adjusting the position of the adjustment structure so that the light rays transmitted through the alignment area can pass through the through-holes on the adjustment structure to achieve a rough alignment between the structure to be detected and the computational holographic structure.

[0009] Furthermore, the process of adjusting the positions of the adjustment structure and the structure to be tested to precisely align the structure to be tested with the interference light-emitting structure includes: adjusting the front and rear positions of the adjustment structure and the structure to be tested so that the light passing through the through hole is as fine as possible.

[0010] Furthermore, in the process of adjusting the front and rear positions of the adjustment structure and the structure to be tested to minimize the light transmitted through the through hole, the process includes: fixing the position of the receiving plate so that the light transmitted through the through hole forms a light spot on the receiving plate; adjusting the front and rear positions of the adjustment structure and the structure to be tested to minimize the width of the light spot; wherein, the light transmitted through the through hole is minimized when the width of the light spot is minimized.

[0011] Furthermore, a scale for measurement is provided on the receiving plate. The scale is used to measure the width of the light spot. The width of the light spot is the smallest when it is smaller than a unit of the scale.

[0012] Furthermore, multiple parallel grid lines are set on the receiving plate, and the width of the light spot is minimized when the width of the light spot is less than the width between two adjacent grid lines.

[0013] Furthermore, a sensor for detecting the width of the light spot is provided on the receiving plate (60). When the sensor detects that the width of the light spot is less than a preset value, the width of the light spot is at its minimum.

[0014] According to another aspect of the present invention, a detection apparatus for detecting aspherical surface shapes is provided. The apparatus employs the aforementioned aspherical surface shape detection method to detect aspherical structures. The apparatus includes an interference light-emitting structure configured to emit interference light; a computational holographic structure having a first region for light transmission, a reflection region for light reflection, and an alignment region for light transmission; and an adjustment structure for assembling the structure to be detected, the adjustment structure having a through-hole that mates with the alignment region.

[0015] The method for detecting aspherical surface shapes using the technical solution of this invention includes: S10: acquiring an interference light-emitting structure, a computational holographic structure, a structure to be detected, and an adjustment structure, and roughly aligning the interference light-emitting structure, the computational holographic structure, the structure to be detected, and the adjustment structure; S20: adjusting the positions of the adjustment structure and the structure to be detected to precisely align the structure to be detected with the interference light-emitting structure; S30: using the interference light-emitting structure to detect the aspherical surface shape of the structure to be detected; wherein, the computational holographic structure is a structure with a computational hologram.

[0016] Before testing, the structure to be tested is assembled onto the adjustment structure to ensure synchronous movement between them. The interferometric emission structure, computational holographic structure, structure to be tested, and adjustment structure are roughly aligned to ensure they are coaxial, and that the interference light emitted from the interferometric emission structure illuminates the structure to be tested and is simultaneously reflected back onto the computational holographic structure, which records the surface shape of the structure to be tested. However, the detection error is relatively large with coarse alignment, necessitating precise alignment. Precise alignment involves adjusting the position of the adjustment structure to change the position of the structure to be tested relative to the computational holographic structure. After precise alignment, the interferometric emission structure detects the surface shape of the structure to be tested. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0018] Figure 1 A schematic diagram of the lens surface shape detection device according to an optional embodiment of the present invention is shown;

[0019] Figure 2 This diagram illustrates the positional relationship between an interferometer, a standard mirror, a computational hologram, an adjustment fixture, and a receiving plate, according to an optional embodiment of the present invention.

[0020] Figure 3A schematic diagram of the structure of a computational hologram according to an optional embodiment of the present invention is shown;

[0021] Figure 4 A diagram showing the positional relationship between the adjustment fixture and the structure being tested, according to an optional embodiment of the present invention, is provided.

[0022] Figure 5 The positional relationship between the adjustment fixture and the structure being inspected is shown in another optional embodiment of the present invention;

[0023] Figure 6 An optical path diagram of a lens surface shape detection device according to an optional embodiment of the present invention is shown;

[0024] Figure 7 It shows Figure 6 Enlarged view of point A in the middle;

[0025] Figure 8 An optical path diagram of a lens surface shape detection device according to another alternative embodiment of the present invention is shown;

[0026] Figure 9 A flowchart of an optional embodiment of the method for detecting aspherical surfaces according to the present invention is shown.

[0027] The above figures include the following reference numerals:

[0028] 10. Interferometer; 20. Standard mirror; 30. Computational holographic structure; 31. Alignment area; 32. Adjustment frame; 33. Computational hologram; 34. First region; 35. Reflection region; 40. Adjustment structure; 41. Through hole; 42. Adjustment component; 43. Adjustment fixture; 44. Mounting area; 50. Structure to be tested; 60. Receiving plate; 100. Interference light output structure. Detailed Implementation

[0029] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0030] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0031] In this invention, unless otherwise stated, directional terms such as "upper," "lower," "top," and "bottom" are generally used in relation to the direction shown in the accompanying drawings, or in relation to the vertical, perpendicular, or gravitational direction of the component itself; similarly, for ease of understanding and description, "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not intended to limit this invention.

[0032] To address the problem of large detection errors in existing technologies for aspherical and freeform surfaces, this invention provides a method for detecting aspherical surface shapes and a detection device for detecting aspherical surface shapes.

[0033] The detection scheme using computational holograms has advantages such as large compensation range, high detection accuracy, and fast detection speed. However, the surface shape error of the detected surface is affected by the adjustment posture of the lens during the detection process. The aspherical surface shape detection method in this application can quickly correct the angular error between the computational hologram and the structure to be detected.

[0034] like Figures 1 to 9 As shown, the method for detecting aspherical surface shapes includes: Step S10: acquiring the interference light-emitting structure 100, the computational holographic structure 30, the structure to be detected 50, and the adjustment structure 40, and roughly aligning the interference light-emitting structure 100, the computational holographic structure 30, the structure to be detected 50, and the adjustment structure 40; Step S20: adjusting the positions of the adjustment structure 40 and the structure to be detected 50 to precisely align the structure to be detected 50 with the interference light-emitting structure 100; Step S30: the interference light-emitting structure 100 detects the aspherical surface shape of the structure to be detected 50; wherein, the computational holographic structure 30 is a structure with a computational hologram 33.

[0035] Before testing, the structure to be tested 50 is assembled onto the adjustment structure 40 so that the structure to be tested 50 and the adjustment structure 40 move synchronously. The interference light-emitting structure 100, the computational holographic structure 30, the structure to be tested 50, and the adjustment structure 40 are roughly aligned to ensure that they are coaxially arranged, and that the interference light emitted by the interference light-emitting structure 100 can illuminate the structure to be tested 50 and be reflected by the structure to be tested 50 onto the computational holographic structure 30, which records the surface shape of the structure to be tested 50. However, the detection error is relatively large under rough alignment, requiring precise alignment. During precise alignment, only the position of the adjustment structure 40 needs to be adjusted to change the position of the structure to be tested 50 relative to the computational holographic structure 30. After precise alignment is completed, the interference light-emitting structure 100 detects the surface shape of the structure to be tested 50.

[0036] During the rough alignment process, it is necessary to adjust the positions of the computational holographic structure 30 and the adjustment structure 40. Adjusting the position of the computational holographic structure 30 facilitates the alignment of the computational holographic structure 30 with the interference light-emitting structure 100, while adjusting the position of the adjustment structure 40 facilitates the alignment of the computational holographic structure 30 with the structure to be detected 50.

[0037] In this embodiment, the process of roughly aligning the interference light-emitting structure 100, the computational holographic structure 30, the structure to be detected 50, and the adjustment structure 40 includes: aligning the interference light-emitting structure 100 with the computational holographic structure 30; and aligning the adjustment structure 40 with the computational holographic structure 30 to roughly align the structure to be detected 50 with the computational holographic structure 30. First, the interference light-emitting structure 100 is aligned with the computational holographic structure 30, and then the adjustment structure 40 is aligned with the computational holographic structure 30 to achieve alignment of the structure to be detected 50 with the computational holographic structure 30, and simultaneously with the interference light-emitting structure 100.

[0038] In one specific embodiment, the process of aligning the interference light-emitting structure 100 with the computational holographic structure 30 includes: the interference light-emitting structure 100 emitting light rays, and the reflection region 35 of the computational holographic structure 30 reflecting the light rays onto the interference light-emitting structure 100; adjusting the position of the computational holographic structure 30 until the interference fringes are adjusted to zero fringes, thus completing the alignment of the computational holographic structure 30 with the interference light-emitting structure 100; wherein the computational holographic structure 30 is configured to have a first region 34 for light transmission, a reflection region 35 for light reflection, and an alignment region 31 for light transmission. By utilizing the properties of interference light, the interference light-emitting structure 100 and the computational holographic structure 30 are aligned so that the light emitted by the interference light-emitting structure 100 can illuminate the computational holographic structure 30. The light is transmitted from the first region 34 to the structure to be detected 50 for detection. Part of the light is reflected by the reflection region 35 to form interference fringes with the incident light. The position of the computational holographic structure 30 is adjusted to adjust the interference fringes to zero fringes, thus completing the alignment of the interference light-emitting structure 100 and the computational holographic structure 30.

[0039] After aligning the computational holographic structure 30 with the interference light-emitting structure 100, the computational holographic structure 30 is aligned with the adjustment structure 40. The process of aligning the adjustment structure 40 with the computational holographic structure 30 to achieve a rough alignment between the structure to be tested 50 and the computational holographic structure 30 includes: the interference light-emitting structure 100 emitting light, the alignment area 31 of the computational holographic structure 30 transmitting light, and adjusting the position of the adjustment structure 40 so that the light transmitted through the alignment area 31 can pass through the through-hole 41 on the adjustment structure 40, thus achieving a rough alignment between the structure to be tested 50 and the computational holographic structure 30. The fact that the light transmitted through the alignment area 31 can pass through the through-hole 41 indicates a preliminary alignment between the computational holographic structure 30 and the adjustment structure 40. However, in this case, the alignment accuracy between the structure to be tested 50 and the computational holographic structure 30 is poor, requiring further adjustment.

[0040] After roughly aligning the adjustment structure 40 with the interference light-emitting structure 100, precise alignment is performed. The process of adjusting the positions of the adjustment structure 40 and the structure to be tested 50 to precisely align the structure to be tested 50 with the interference light-emitting structure 100 includes adjusting the relative positions of the adjustment structure 40 and the structure to be tested 50 to minimize the light transmitted through the through-hole 41. The error is minimized when the light transmitted through the through-hole 41 is at its minimum, or when the width of the light spot formed by the light transmitted through the through-hole 41 is minimized.

[0041] It should be noted that there are multiple alignment areas 31 around the first region 34, and multiple through holes on the adjustment structure 40. The multiple alignment areas 31 and multiple through holes 41 correspond to each other. When light passes through all the through holes 41, the adjustment structure 40 and the computational holographic structure 30 are roughly aligned.

[0042] Preferably, there are four alignment areas 31 and four through holes 41, and the four alignment areas 31 are respectively set in the four directions of up, down, left and right. In this way, when the structure 40 is tilted, the light transmitted through at least one through hole 41 will change, or even cannot pass through one of the through holes 41, which can be quickly observed and effectively reduce detection errors.

[0043] In this embodiment, the process of adjusting the front and rear positions of the adjustment structure 40 and the structure to be detected 50 to minimize the light transmitted through the through hole 41 includes: fixing the position of the receiving plate 60 so that the light transmitted through the through hole 41 forms a light spot on the receiving plate 60; adjusting the front and rear positions of the adjustment structure 40 and the structure to be detected 50 to minimize the width of the light spot; wherein, the through hole 41 transmits the light most finely when the width of the light spot is minimized. After the position of the receiving plate 60 is fixed, the position of the adjustment structure 40 along the optical axis is adjusted so that when the width of the light spot received on the receiving plate is minimized, the cursor projected through the alignment area 31 at this time exactly converges on the surface of the adjustment structure 40 facing the receiving plate 60.

[0044] In an optional embodiment, the receiving plate 60 is provided with a scale for measurement. The scale measures the width of the light spot, with the width of the light spot being the smallest when it is less than a unit of the scale. This arrangement allows the width of the light spot to be obtained directly from the receiving plate 60, facilitating the adjustment structure 40. The size of the unit scale can be designed according to actual usage requirements.

[0045] Of course, the unit of the scale can also be fixed, and the width of the light spot can be recorded in real time when the position of the adjustment structure 40 is adjusted, and the position of the adjustment structure 40 can be adjusted when the width of the light spot is the smallest.

[0046] It should be noted that when adjusting the position of the adjustment structure 40, the width of the light spot first decreases and then increases with the position of the adjustment structure 40, so the width of the light spot has a minimum value.

[0047] In another optional embodiment, a plurality of parallel grid lines are provided on the receiving plate 60. The width of the light spot is minimized when the width of the light spot is less than the width between two adjacent grid lines. Alternatively, grid lines can be provided, and the light spot is considered to have reached its minimum width when the width of the grid lines is less than the distance between two adjacent grid lines. It should be noted that the multiple grid lines are equally spaced, and the distance between the grid lines is a preset distance, the size of which can be designed according to actual usage requirements.

[0048] Of course, the distance between two adjacent grid lines can also be fixed. When adjusting the position of the adjustment structure 40, the width of the light spot is recorded in real time, and the position of the adjustment structure 40 is adjusted when the width of the light spot is the smallest.

[0049] In another optional embodiment, a sensor for detecting the width of the light spot is provided on the receiving plate 60. When the sensor detects that the width of the light spot is less than a preset value, the light spot width is considered to be at its minimum. Detecting the light spot width using a sensor ensures detection accuracy. The size of the preset value can be designed according to specific usage requirements.

[0050] Of course, when adjusting the position of the adjustment structure 40, the sensor records the width of the light spot in real time, and adjusts the position of the adjustment structure 40 when the width of the light spot is the smallest. The detection device for detecting aspherical surface shapes uses the above-mentioned aspherical surface shape detection method to detect aspherical structures. The detection device for detecting aspherical surface shapes includes an interference light-emitting structure 100, which can be configured to emit interference light; a computational holographic structure 30, which has a first region 34 for light transmission, a reflection region 35 for light reflection, and an alignment region 31 for light transmission; and an adjustment structure 40, which is used to assemble the structure to be detected 50, and has a through hole 41 that mates with the alignment region 31.

[0051] The interference beam structure 100 includes an interferometer 10 and a standard mirror 20. The interferometer 10 generates interference light to facilitate subsequent alignment and detection using the interference fringes produced by the interference light. The standard mirror 20 provides spherical waves with different apertures to facilitate the detection of different structures 50 to be tested. The computational holographic structure 30 is used to transmit a reference and is also used for detection. The adjustment structure 40 is mainly used to adjust the position of the structure 50 to be tested in the optical path. The standard mirror 20, the computational holographic structure 30, and the structure 50 to be tested are all on the central optical axis of the beam output from the interferometer 10. By setting an alignment region 31 on the computational holographic structure 30 and a through-hole 41 on the structure 50 to be tested, the light emitted through the alignment region 31 can enter the through-hole 41, thus aligning the computational holographic structure 30 with the adjustment structure 40, and consequently aligning the structure 50 to be tested with the computational holographic structure 30, ensuring the accuracy of the detection of the structure 50 to be tested. By setting the alignment area 31 and the through hole 41 in combination, the adjustment time between the holographic structure 30 and the adjustment structure 40 can be reduced, and the alignment error can also be reduced.

[0052] It should be noted that the computational holographic structure 30 refers to a structure with a computational hologram 33, or a hologram that records all the information of the light waves of a real or virtual object. It reproduces a hologram with physical depth of field, is viewable with the naked eye, and can be decoded by a computer, but it does not possess computational capabilities itself. Specifically, one side surface of the structure to be detected 50 reflects light onto the computational hologram 33, which records the reflected information. After computer decoding, it can present the three-dimensional surface information of the structure to be detected 50.

[0053] like Figures 1 to 3As shown, the computational holographic structure 30 includes an adjustment frame 32 and a computational hologram 33. The computational hologram 33 is mounted on the adjustment frame 32. The position of the computational hologram 33 is adjusted by adjusting the position of the adjustment frame 32. The computational hologram 33 has a first region 34 and a second region arranged coaxially. The first region 34 is located inside the second region, or in other words, the reflection region 35 and the alignment region 31 form the second region. The reflection region 35 can reflect light to align the computational holographic structure 30 with the interferometer 10. The first region 34 can transmit light to detect the surface shape of the structure 50 to be detected. When adjusting the position of the computational hologram 33, the user moves it by picking up the adjustment frame 32 to reduce collisions with the computational hologram 33 and minimize its impact. A first region 34 and a second region are provided on the computational hologram 33. The first region 34 is capable of transmitting light, and the light transmitted through the first region 34 can illuminate the structure to be detected 50. The structure to be detected 50 reflects the light onto the computational hologram 33, and the light is recorded by the computational hologram 33. The second region has an alignment region 31 and a reflection region 35 other than the alignment region 31. The reflection region can reflect the light emitted from the standard mirror 20, so as to facilitate the alignment of the standard mirror 20 and the computational hologram 33. During the alignment process of the standard mirror 20 and the computational hologram 33, the light output from the interferometer 10 is emitted onto the computational hologram 33 through the standard mirror 20. The reflection region reflects the light, and the reflected light path returns to the interferometer 10 and forms interference fringes. The position of the computational hologram 33 is adjusted until the interference fringes disappear.

[0054] It should be noted that a reflective grating is provided on the reflective area 35 to achieve the reflective effect.

[0055] like Figure 2 and Figure 3 As shown, there are multiple alignment regions 31, which are equally spaced around the outer periphery of the first region 34. This arrangement allows the alignment regions 31 to be positioned in multiple locations and directions, so that the computational hologram 33 is aligned with the adjustment structure 40 in multiple directions, greatly improving the alignment accuracy between the computational hologram 33 and the adjustment structure 40.

[0056] like Figure 1 , Figure 2 , Figure 4 and Figure 5As shown, the adjustment structure 40 includes an adjustment component 42 and an adjustment fixture 43. The adjustment fixture 43 is disposed on the adjustment component 42 and has an installation area 44. The structure to be tested 50 is disposed within the installation area 44, which corresponds to the first area 34. Multiple through holes 41 are arranged at intervals around the circumference of the installation area 44, and each through hole 41 corresponds one-to-one with a multiple alignment area 31. The installation area 44 is used to install the structure to be tested 50, thus confining it within a specific area. The multiple through holes 41 are arranged at intervals around the circumference of the installation area 44, ensuring that each through hole 41 corresponds one-to-one with a multiple alignment area 31. This aligns the installation area 44 with the first area 34, thereby ensuring alignment between the structure to be tested 50 and the first area 34 and reducing errors during the testing process.

[0057] Preferably, multiple through holes 41 are arranged at equal intervals.

[0058] Optionally, the adjustment fixture 43 has a receiving groove, the area within which is the mounting area 44, and at least a portion of the structure 50 to be inspected is located within the receiving groove. The receiving groove in the adjustment fixture 43 reduces misalignment of the structure 50, and after initial alignment, the position of the structure 50 to be inspected is less likely to change, effectively reducing inspection errors.

[0059] It should be noted that even if the tooling 43 is tilted, as long as the light emitted from the alignment area 31 can pass through the through hole 41, the structure to be tested 50 can be illuminated by the light transmitted through the first area 34, and this is the alignment state.

[0060] Specifically, the aspherical surface of the structure to be detected 50 is oriented towards the computational holographic structure 30. The computational holographic structure 30 can detect the surface shape of aspherical surfaces, and of course, it can also detect the surface shape of freeform surfaces.

[0061] Optionally, the shape of the through hole 41 is the same as the shape of the alignment area 31. With this setting, the shape of the displayed light spot is consistent with the shape of the through hole 41 only after the through hole 41 and the alignment area 31 are completely aligned. By observing the shape of the light spot, one can make a preliminary judgment on whether the through hole 41 and the alignment area 31 are aligned, effectively saving judgment time.

[0062] Optionally, the through hole 41 can be square or circular.

[0063] exist Figure 4In the specific embodiments shown, the through-hole 41 is an elongated hole, and the elongated hole can be a horizontal "one", a vertical "1", or of course, inclined. At this time, the alignment area 31 is also an elongated hole, which can be a horizontal "one", a vertical "1", or inclined.

[0064] In Figure 5 the specific embodiments shown, the shape of the through-hole 41 can also be cross-shaped, and correspondingly, the alignment area 31 is also cross-shaped.

[0065] As Figure 1 and Figure 2 shown, the lens surface shape detection device further includes a receiving plate 60. The receiving plate 60 is arranged on the side of the adjustment structure 40 away from the computer-generated hologram structure 30. The receiving plate 60 is used to receive the light transmitted through the through-hole 41. The receiving plate 60 can receive the light transmitted through the through-hole 41 to form a light spot on the receiving plate 60. By observing the light spot, it can be judged whether the computer-generated hologram 33 is aligned with the structure 50 to be detected, reducing the light irradiation on the human eye and reducing the damage to the eyes. At the same time, the setting of the receiving plate 60 enables the light spot to be observed intuitively, facilitating the observer to observe.

[0066] It should be noted that the receiving plate 60 can be paper, cardboard, etc.

[0067] As Figure 2 shown, the interferometer 10 is connected to the reference mirror 20. The connection of the interferometer 10 and the reference mirror 20 together eliminates the need to adjust the alignment between the interferometer 10 and the reference mirror 20, reducing the working process and increasing the working efficiency.

[0068] In Figure 6 the specific embodiments shown, it is the optical path for the lens surface shape detection device to detect an off-axis concave aspherical surface.

[0069] In Figure 8 the specific embodiments shown, it is the optical path for the lens surface shape detection device to detect an off-axis convex aspherical surface. In this embodiment, since the optical path is shorter, it is more beneficial for the detector to quickly adjust the optical path to the optimal position during the detection of the convex aspherical surface.

[0070] Of course, the structure in the present application can also detect the surface shape of a coaxial aspherical surface.

[0071] Obviously, the above-described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present invention.

[0072] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0073] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.

[0074] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for detecting aspherical surface shapes, characterized in that, include: Obtain the interference light-emitting structure (100), the computational holographic structure (30), the structure to be detected (50), and the adjustment structure (40), and roughly align the interference light-emitting structure (100), the computational holographic structure (30), the structure to be detected (50), and the adjustment structure (40); Adjust the positions of the adjustment structure (40) and the structure to be tested (50) to precisely align the structure to be tested (50) with the interference light-emitting structure (100); The interference light-emitting structure (100) detects the aspherical surface shape of the structure to be detected (50); The computational holographic structure (30) is a structure having a computational hologram (33); The process of roughly aligning the interference light-emitting structure (100), the computational holographic structure (30), the structure to be detected (50), and the adjustment structure (40) includes: Align the interference light-emitting structure (100) with the computational holographic structure (30); Align the adjustment structure (40) with the computational holographic structure (30) to roughly align the structure to be detected (50) with the computational holographic structure (30); The process of aligning the adjustment structure (40) with the computational holographic structure (30) to coarsely align the structure to be detected (50) with the computational holographic structure (30) includes: The interference light-emitting structure (100) emits light rays, and the alignment region (31) of the computational holographic structure (30) transmits the light rays; The position of the adjustment structure (40) is adjusted so that the light passing through the alignment area (31) can pass through the through hole (41) on the adjustment structure (40) to achieve a rough alignment between the structure to be detected (50) and the computational holographic structure (30).

2. The method for detecting aspherical surface shapes according to claim 1, characterized in that, The process of aligning the interference light-emitting structure (100) with the computational holographic structure (30) includes: The interference light-emitting structure (100) emits light rays, and the reflection region (35) of the computational holographic structure (30) reflects the light rays onto the interference light-emitting structure (100); Adjust the position of the computational holographic structure (30) until the interference fringes are adjusted to zero fringes, thus completing the alignment of the computational holographic structure (30) with the interference light-emitting structure (100); The computational holographic structure (30) is configured to have a first region (34) for light transmission, a reflective region (35) for light reflection, and an alignment region (31) for light transmission.

3. The method for detecting aspherical surface shapes according to claim 1, characterized in that, The process of adjusting the positions of the adjustment structure (40) and the structure to be tested (50) to precisely align the structure to be tested (50) with the interference light-emitting structure (100) includes: Adjust the front and rear positions of the adjustment structure (40) and the structure to be tested (50) so that the light passing through the through hole (41) is as fine as possible.

4. The method for detecting aspherical surface shapes according to claim 3, characterized in that, In the process of adjusting the front and rear positions of the adjustment structure (40) and the structure to be detected (50) to minimize the light transmitted through the through hole (41), the following steps are included: The position of the receiving plate (60) is fixed so that the light transmitted through the through hole (41) forms a light spot on the receiving plate (60); Adjust the front and rear positions of the adjustment structure (40) and the structure to be detected (50) to minimize the width of the light spot; When the width of the light spot is the smallest, the light transmitted through the through hole (41) is the thinnest.

5. The method for detecting aspherical surface shapes according to claim 4, characterized in that, The receiving plate (60) is provided with a scale for measurement. The scale is used to measure the width of the light spot. The width of the light spot is the minimum when it is less than a unit of the scale.

6. The method for detecting aspherical surface shapes according to claim 4, characterized in that, The receiver plate (60) has a plurality of parallel grid lines. The width of the light spot is minimized when the width of the light spot is less than the width between two adjacent grid lines.

7. The method for detecting aspherical surface shapes according to claim 4, characterized in that, A sensor for detecting the width of the light spot is provided on the receiving plate (60). When the sensor detects that the width of the light spot is less than a preset value, the width of the light spot is at its minimum.

8. A detection device for detecting aspherical surface shapes, characterized in that, The detection device for detecting aspherical surfaces employs the aspherical surface detection method according to any one of claims 1 to 7 to detect the aspherical structure. An interference light-emitting structure (100) is configured to emit interference light; The computational holographic structure (30) has a first region (34) for light transmission, a reflective region (35) for light reflection, and an alignment region (31) for light transmission. An adjustment structure (40) is used to assemble the structure to be tested (50), and the adjustment structure (40) has a through hole (41) that mates with the alignment area (31).

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