Composite MLA detection method and detection device for LED array

Abstract

The present invention discloses a composite MLA detection method and detection device for an LED array, wherein the LED array includes a microlens array, and the microlens array includes a plurality of sub-lenses arranged in an array, and the detection method includes: obtaining a plurality of light spot images corresponding to each of the sub-lenses; processing the light spot images to determine the consistency detection results of the sub-lenses; wherein the consistency detection results include at least one of the detection results of PSF consistency, MTF consistency, and position consistency; based on the consistency detection results of the sub-lenses, determining the composite MLA detection results of the microlens array. The composite MLA detection method provided by the present invention can detect the sub-lens position, PSF, and MTF consistency of the MLA, and is used to feedback the production process, make timely adjustments to the products in production, improve the yield, and reduce quality risks.

Description

Technical Field

[0001] The present invention relates to the technical field of lens detection, and in particular to a composite MLA detection method and a detection device for an LED array. Background Art

[0002] Microlens array (MLA) has important and extensive applications in optical systems. Microlens array has the functions of converging light energy, correcting aberrations and imaging. It is widely used in infrared photodetectors, image recognition and processing, optical communications, laser medicine, space optics and many other fields due to its small size, light weight, high integration and easy replication.

[0003] However, in the actual production process, there is no good detection method for microlens arrays to determine whether they are qualified. At present, the main method of detecting microlens arrays is to measure them through equipment such as profilometers and atomic force microscopes. Using a microscope can only observe fine structures one by one, and it is not possible to determine whether the microlenses in the microlens array are distorted or whether the array is uniform and consistent on a macro scale. This method is not only costly and inefficient, but also easy to cause secondary damage and contamination to the microlens array due to direct contact between the probe and the surface of the object being measured. Therefore, most companies on the market can only use small-batch trial production methods to determine whether the microstructure of the microlens array in this batch is qualified through visual observation of the finished product, and then organize mass production.

[0004] However, there are many uncertain factors in the production process of microlens arrays. If the quality of microlens arrays can only be judged by trial production, it is obviously a big risk for microlens array manufacturers. Therefore, it is urgent to develop a microlens array microstructure detection device.

[0005] The disclosure of the above background technology content is only used to assist in understanding the inventive concept and technical solution of the present invention. It does not necessarily belong to the prior art of this patent application, nor does it necessarily provide technical guidance. In the absence of clear evidence that the above content has been disclosed before the filing date of this patent application, the above background technology should not be used to evaluate the novelty and creativity of the present application. Summary of the invention

[0006] The purpose of the present invention is to provide a composite MLA detection method and detection device for LED arrays, which can realize the sub-lens position consistency detection, point spread function (PSF) consistency detection and modulation transfer function (MTF) consistency detection of the microlens array, and can quantitatively, large-scale and quickly judge the quality of the microlens array, so as to provide feedback on the production process, make timely adjustments to the product, improve the yield and reduce quality risks.

[0007] On the one hand, in order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is as follows:

[0008] A composite MLA detection method for an LED array is provided, wherein the LED array includes a microlens array, wherein the microlens array includes a plurality of sub-lenses arranged in an array, and the detection method includes:

[0009] Acquire a plurality of light spot images corresponding to each of the sub-lenses;

[0010] Processing the spot image to determine a consistency detection result of the sub-lens; wherein the consistency detection result includes at least one of a PSF consistency detection result, an MTF consistency detection result, and a position consistency detection result;

[0011] Wherein, the detection result of the PSF consistency of the sub-lens is determined in the following manner: obtaining a PSF image of each of the sub-lens, wherein the PSF image includes an image of a light spot corresponding to the sub-lens; calculating a corresponding PSF similarity value based on the PSF image of each of the sub-lens, and / or calculating an area difference between a corresponding light spot and a theoretical light spot based on the PSF image of each of the sub-lens; determining the detection result of the PSF consistency of the sub-lens based on the PSF similarity value corresponding to the sub-lens and / or the area difference;

[0012] Based on the consistency detection results of the sub-lenses, a composite MLA detection result of the microlens array is determined.

[0013] Further, based on any one of the technical solutions or a combination of multiple technical solutions described above, the PSF image includes an original PSF image and a simulated PSF image, and obtaining the PSF image of each of the sub-lenses includes: determining the original PSF image of each sub-lens from a plurality of spot images of each of the sub-lens; and obtaining a simulated PSF image corresponding to each of the original PSF images;

[0014] The detection result of determining the PSF consistency of the sub-lens based on the PSF similarity value corresponding to the sub-lens includes:

[0015] Determine the original PSF image of each sub-lens from the multiple spot images of each sub-lens;

[0016] Expanding the original PSF image of each sub-lens to obtain an expanded PSF image, which is recorded as an expanded PSF image;

[0017] Acquire a simulated PSF image of each of the sub-lenses;

[0018] Based on the original PSF image, the expanded PSF image and the simulated PSF image, the PSF similarity value corresponding to each of the sub-lenses is calculated, and then the detection result of the PSF consistency of the sub-lenses is determined.

[0019] Further, based on any one of the above-mentioned technical solutions or a combination of multiple technical solutions, the calculating of the PSF similarity value corresponding to each sub-lens based on the original PSF image, the expanded PSF image and the simulated PSF image includes:

[0020] Calculating a similarity value between the original PSF image and the simulated PSF image, recorded as a first similarity value;

[0021] Calculating a similarity value between the expanded PSF image and the simulated PSF image, recorded as a second similarity value;

[0022] A weighted sum is performed on the first similarity value and the second similarity value to obtain the PSF similarity value.

[0023] Further, based on any one of the above-mentioned technical solutions or a combination of multiple technical solutions, the determining the original PSF image of each sub-lens from the multiple spot images of each sub-lens includes: calculating the gradient values ​​of the multiple spot images of each sub-lens; determining the spot image with the largest gradient value among all the spot images of each sub-lens as the original PSF image of the sub-lens;

[0024] And / or, the expanding the original PSF image of each of the sub-lenses includes: performing log expansion on the original PSF image using the following formula: ;in, I is the normalized grayscale matrix of the original PSF image, I’ is the grayscale matrix of the expanded PSF image, ε and δ are two weighting coefficients.

[0025] Further, based on any one of the above-mentioned technical solutions or a combination of multiple technical solutions, the detection result of determining the PSF consistency of the sub-lens based on the area difference corresponding to the sub-lens includes:

[0026] Determine the area of ​​the light spot in the original PSF image of each sub-lens, and record it as the actual light spot area of ​​each sub-lens;

[0027] Obtaining a theoretical spot area of ​​the sub-lens;

[0028] The area difference between the actual spot area and the theoretical spot area of ​​each sub-lens is calculated, and then the detection result of the PSF consistency of the sub-lens is determined.

[0029] Further, based on any one of the above-mentioned technical solutions or a combination of multiple technical solutions, the detection result of determining the PSF consistency of the sub-lens based on the PSF similarity value and / or area difference value corresponding to the sub-lens includes:

[0030] If the PSF similarity value corresponding to the sub-lens meets the PSF consistency standard, and the area difference value corresponding to the sub-lens meets the PSF consistency standard, then the PSF consistency detection result of the sub-lens is determined to be qualified.

[0031] Further, based on any one of the above-mentioned technical solutions or a combination of multiple technical solutions, the detection result of the MTF consistency of the sub-lens is determined by the following method:

[0032] Determine an original PSF image of each sub-lens from a plurality of spot images of each sub-lens;

[0033] Performing frequency domain transformation on the original PSF image of each sub-lens to obtain a current MTF image of each sub-lens;

[0034] Obtaining simulated MTF images of each sub-lens;

[0035] The similarity between the current MTF image of each sub-lens and the corresponding simulated MTF image is calculated to obtain the MTF similarity value of each sub-lens, and then determine the detection result of the MTF consistency of the sub-lens.

[0036] Further, based on any one of the above-mentioned technical solutions or a combination of multiple technical solutions, the calculating the similarity between the current MTF image and the simulated MTF image of each sub-lens includes:

[0037] Performing multiple synchronous sampling on the same points of the current MTF image and the simulated MTF image to obtain multiple first MTF values ​​and corresponding second MTF values ​​respectively;

[0038] Based on the multiple first MTF values ​​and the corresponding second MTF values, an average value of the MTF similarity values ​​of the sampling points corresponding to the multiple synchronous samplings is calculated, and recorded as the MTF similarity value of each of the sub-lenses, wherein the MTF similarity value of the sampling point is related to the ratio of the first MTF value to the second MTF value at the sampling point;

[0039] And / or, the detection result of determining the MTF consistency of the sub-lens includes:

[0040] It is determined whether the MTF similarity value of each of the sub-lenses is greater than a preset MTF similarity threshold value. If so, the detection result of the MTF consistency of the sub-lens is qualified; otherwise, the detection result of the MTF consistency of the sub-lens is unqualified.

[0041] Further, based on any one of the above-mentioned technical solutions or a combination of multiple technical solutions, the MTF similarity value of the sub-lens is calculated using the following formula:

[0042]

[0043] in, P is the MTF similarity value of the sub-lens, For location ( Xi , Yi ), For location ( Xi , Yi ), N is the number of the first MTF value.

[0044] Further, based on any one of the above-mentioned technical solutions or a combination of multiple technical solutions, the position consistency of the sub-lenses is determined by the following method:

[0045] Selecting the most focused spot image from the multiple spot images corresponding to each sub-lens, and recording it as the focused spot image;

[0046] Determine the centroid of the light spot in the focused light spot image of each sub-lens;

[0047] According to the centroids of the light spots corresponding to all the sub-lenses, straight line fitting is performed in the row direction and the column direction to obtain the fitting straight lines corresponding to each row and each column;

[0048] Obtaining the distance from the center of mass of the light spot corresponding to each sub-lens to the fitting straight line corresponding to its row and column as the position deviation of the sub-lens; wherein the position deviation includes row deviation and column deviation;

[0049] According to the position deviation of each of the sub-lenses, a detection result of the position consistency of the sub-lenses is determined.

[0050] Further, based on any one of the above-mentioned technical solutions or a combination of multiple technical solutions, the detection result of determining the position consistency of the sub-lens according to the position deviation of each sub-lens includes:

[0051] It is determined whether the row deviation and column deviation of each sub-lens are within the corresponding preset deviation range. If so, the detection result of the position consistency of the sub-lens is qualified; otherwise, the detection result of the position consistency of the sub-lens is unqualified.

[0052] Further, based on any one of the above-mentioned technical solutions or a combination of multiple technical solutions, the step of obtaining a plurality of light spot images corresponding to each of the sub-lenses includes:

[0053] Acquire a plurality of array spot images, wherein the array spot image includes an image of a spot corresponding to each of the sub-lenses;

[0054] Performing image clarity calculation on the multiple array light spot images to select a focused array light spot image from the multiple array light spot images;

[0055] Performing filtering and noise reduction processing on the focused array spot image to obtain a filtered image;

[0056] Performing circular detection processing on the filtered image to obtain the center coordinates of each light spot in the focusing array light spot image;

[0057] Each of the array spot images is cropped based on the circle center coordinates to obtain multiple spot images of each sub-lens.

[0058] Further, based on any one of the above-mentioned technical solutions or a combination of multiple technical solutions, the determination of the composite MLA detection result of the microlens array based on the consistency detection result of the sub-lens includes:

[0059] Determine the number of sub-lenses whose PSF consistency test results, MTF consistency test results, and position consistency test results are all qualified;

[0060] If the lens proportion value of the number of the sub-lenses in the lens LED array reaches a preset ratio threshold, the composite MLA detection result of the LED microlens array is qualified.

[0061] According to another aspect of the present invention, a detection device is provided, the detection device comprising a light source, a collimator, a stage, a microscope objective lens and a camera arranged in sequence along a light path direction, the stage being configured to carry a microlens array to be detected, the microlens array comprising a plurality of sub-lenses arranged in an array, the light emitted by the light source passing through the collimator is incident on the microlens array, and the microscope objective lens is configured to guide the light at the microlens array to the camera;

[0062] The detection device also includes a computer, which is configured to obtain the array spot image captured by the camera and process the array spot image to determine the composite MLA detection result of the microlens array; wherein the composite MLA detection result includes at least one of the detection result of position consistency, the detection result of PSF consistency and the detection result of MTF consistency.

[0063] Further, based on any one of the technical solutions or a combination of multiple technical solutions mentioned above, the camera forms an image when the following conditions are met: a star point is used in the collimator, and the light spot formed by focusing after the microlens array is smaller than the diffraction limit of the detection device; the camera is adjusted to a focusing position, and the optical axis distance between the camera and the stage in this state is defined as a reference distance; the camera and / or the stage are moved along the optical axis so that their optical axis distance floats based on the reference distance, and the floating distance is an integer multiple of the depth of focus distance; multiple floats are performed, and the camera captures corresponding array spot images.

[0064] Further, based on any one of the technical solutions or a combination of multiple technical solutions described above, the detection device also includes a Perot plate, a horizontal driving mechanism for driving the stage to move in a two-dimensional plane, and a vertical driving mechanism for driving the camera or the stage to move along the optical axis direction of the optical path; when the Perot plate is placed in the collimator, the horizontal driving mechanism drives the stage to move until the light emitted from the collimator is incident on the microlens array; and when the camera is located at the focal plane position under the drive of the vertical driving mechanism, the Perot plate in the collimator is replaced by the star point;

[0065] And / or, the magnification of the microscope objective lens is determined by the focal length of the microlens array to be detected, the focal length of the collimator, and the pixel size of the camera;

[0066] And / or, the light source is monochromatic incoherent light, and the wavelength of the monochromatic incoherent light is determined by the design wavelength of the microlens array to be detected.

[0067] Further, based on any one of the technical solutions or a combination of multiple technical solutions mentioned above, the computer is configured to execute the detection method as described above.

[0068] The beneficial effects brought by the technical solution provided by the present invention are as follows:

[0069] a. Through the coordination of various components of the detection equipment, the computer receives the image of the star point formed by the sub-lenses of the microlens array, and detects the position, PSF and MTF consistency of the sub-lenses of the microlens array.

[0070] b. The detection equipment provided by the present invention can quantitatively, large-scale and quickly judge the structural quality of the microlens array, and provide feedback on the production process by detecting the position, PSF and MTF consistency of the sub-lenses of the microlens array, so as to make timely adjustments to the products in production, improve the yield rate and reduce quality risks. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0072] Figure 1 A flow chart of a composite MLA detection method for an LED array provided for an exemplary embodiment of the present invention;

[0073] Figure 2 A flow chart of a method for detecting position consistency of sub-lenses provided for an exemplary embodiment of the present invention;

[0074] Figure 3 A flow chart of a first method for determining the PSF consistency of a sub-lens provided for an exemplary embodiment of the present invention;

[0075] Figure 4 A flow chart of a second method for determining the PSF consistency of a sub-lens provided by an exemplary embodiment of the present invention;

[0076] Figure 5 A flow chart of a third method for determining the PSF consistency of a sub-lens provided for an exemplary embodiment of the present invention;

[0077] Figure 6 A flow chart of a method for detecting the MTF consistency of a sub-lens provided for an exemplary embodiment of the present invention;

[0078] Figure 7 A schematic diagram of a detection device provided for an exemplary embodiment of the present invention;

[0079] Among them, 1-light source, 2-collimator, 3-Perot plate, 4-x Axis Precision Stage, 5- y Axis precision translation stage, 6-stage, 7-microlens array, 8- z Axis precision translation stage, 9-microscope objective lens, 10-camera, 11-computer. DETAILED DESCRIPTION

[0080] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0081] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, device, product or equipment that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or equipment.

[0082] In one embodiment of the present invention, a composite MLA detection method for an LED array is provided, wherein the LED array includes a microlens array, and the microlens array includes a plurality of sub-lenses arranged in an array, such as Figure 1 As shown, the detection method includes:

[0083] S1: Acquire multiple spot images corresponding to each sub-lens.

[0084] The spot image may be a grayscale image. In order to obtain multiple spot images corresponding to each sub-lens, an array spot image may be first obtained using a camera, wherein the array spot image includes the image of the spot corresponding to each sub-lens; and then the spot image of each sub-lens is cropped from the array spot image. For example, in order to improve the image quality of the spot image of the sub-lens, N array spot images are obtained, and N spot images of each sub-lens can be obtained by cropping.

[0085] Furthermore, the cropping needs to determine the center of the light spot in the light spot image of each sub-lens. In this embodiment, the following method is adopted:

[0086] S11: performing image clarity calculation on a plurality of array light spot images to select a focused array light spot image from the plurality of array light spot images.

[0087] The purpose of clarity calculation is to select an image with the best focus for circular detection and coordinate extraction of the light spot.

[0088] S12: Perform filtering and noise reduction processing on the focused array spot image to obtain a filtered image.

[0089] In this embodiment, the filtering noise reduction first uses median filtering to reduce the noise of salt and pepper noise, and then uses Gaussian filtering to reduce the noise of Gaussian noise.

[0090] S13: Performing circle detection processing on the filtered image to obtain the center coordinates of each light spot in the focusing array light spot image.

[0091] S14: cropping each array spot image based on the circle center coordinates to obtain multiple spot images of each sub-lens.

[0092] S2: Processing the spot image to determine a consistency detection result of the sub-lens; wherein the consistency detection result includes at least one of a PSF consistency detection result, an MTF consistency detection result, and a position consistency detection result.

[0093] The test results of PSF consistency, MTF consistency and position consistency include qualified and unqualified.

[0094] Among them, the PSF consistency test aims to detect whether the actual PSF index of a sub-lens is consistent with the theoretical PSF index or not; the MTF consistency test aims to detect whether the actual MTF index of a sub-lens is consistent with the theoretical MTF index or not; the position consistency test aims to detect whether the actual position of a sub-lens is consistent with the theoretical position or not.

[0095] S3: Determine a composite MLA detection result of the microlens array based on the consistency detection result of the sub-lenses.

[0096] In one embodiment, when the consistency detection results of the sub-lenses include the detection results of the position consistency, the number of sub-lenses with qualified positions can be counted, and then it is determined whether the lens ratio value of the sub-lenses with qualified positions in the microlens array reaches a preset qualified ratio threshold; if the lens ratio value of the sub-lenses with qualified positions in the microlens array reaches the preset qualified ratio threshold, the composite MLA detection result of the microlens array is determined to be qualified; if the lens ratio value of the sub-lenses with qualified positions in the microlens array does not reach the preset qualified ratio threshold, the composite MLA detection result of the microlens array is determined to be unqualified.

[0097] In another embodiment, when the consistency test results of the sub-lenses include the test results of the PSF consistency, it can be determined whether the lens ratio of the sub-lenses with qualified PSF in the microlens array reaches a preset qualified ratio threshold. If the lens ratio of the sub-lenses with qualified PSF in the microlens array reaches the preset qualified ratio threshold, the composite MLA test result of the microlens array is determined to be qualified; if the lens ratio of the sub-lenses with qualified PSF in the microlens array does not reach the preset qualified ratio threshold, the composite MLA test result of the microlens array is determined to be unqualified.

[0098] In another embodiment, when the consistency test results of the sub-lenses include the test results of the MTF consistency, the number of sub-lenses with qualified MTF can be counted, and then it is determined whether the proportion of sub-lenses with qualified MTF to all sub-lenses reaches a preset proportion threshold; if the proportion of sub-lenses with qualified MTF to all sub-lenses does not reach the preset proportion threshold, the composite MLA test result of the microlens array is determined to be unqualified.

[0099] In other embodiments, when the consistency test results of the sub-lenses include the test results of PSF consistency, the test results of MTF consistency and the test results of position consistency, the number of sub-lenses whose PSF consistency test results, MTF consistency test results and position consistency test results are all qualified can be determined first; then it is determined whether the lens ratio value of the number of sub-lenses whose three test results are all qualified in the microlens array reaches a preset ratio threshold; if the lens ratio value of the number of sub-lenses that are all qualified in the microlens array reaches the preset ratio threshold, then the composite MLA test result of the microlens array is determined to be qualified; if the lens ratio value of the number of sub-lenses that are all qualified in the microlens array does not reach the preset ratio threshold, then the composite MLA test result of the microlens array is determined to be unqualified.

[0100] It can be understood that if the consistency test results only include the test results of PSF consistency and the test results of MTF consistency, the number of sub-lenses whose PSF consistency test results and MTF consistency test results are both qualified is first determined; then it is determined whether the lens ratio value of the number of sub-lenses whose two test results are both qualified in the microlens array reaches a preset ratio threshold; if the lens ratio value of the number of sub-lenses that are both qualified in the microlens array reaches the preset ratio threshold, the composite MLA test result of the microlens array is determined to be qualified; if the lens ratio value of the number of sub-lenses that are both qualified in the microlens array does not reach the preset ratio threshold, the composite MLA test result of the microlens array is determined to be unqualified.

[0101] It can be understood that when the consistency detection results of the sub-lenses include the detection results of the PSF consistency, the MTF consistency and the position consistency, it can also be determined whether the lens ratio value of the number of sub-lenses with qualified positions in the microlens array reaches a first preset ratio threshold, whether the lens ratio value of the number of sub-lenses with qualified PSF in the microlens array reaches a second preset ratio threshold, and whether the lens ratio value of the number of sub-lenses with qualified MTF in the microlens array reaches a third preset ratio threshold. If so, it is determined that the composite MLA detection result of the microlens array is qualified; if not, it is determined that the composite MLA detection result of the microlens array is unqualified.

[0102] Furthermore, the preset ratio threshold and specific values ​​of the first preset ratio threshold to the third preset ratio threshold can be set according to specific application requirements, and the present invention does not limit this.

[0103] It is worth noting that the composite MLA detection method for LED arrays provided by the present invention can quantitatively, large-scale and quickly judge the structural quality of the microlens array. By detecting the position, PSF and MTF consistency of the sub-lenses of the microlens array, feedback can be provided on the production process, and adjustments can be made to the products in production in a timely manner, thereby improving the yield and reducing quality risks.

[0104] In one embodiment of the present invention, Figure 2 As shown, the position consistency of the sub-lenses is determined by:

[0105] S21a: Select the most focused spot image from the multiple spot images corresponding to each sub-lens, and record it as the focused spot image.

[0106] Exemplarily, the most focused spot image is selected from the multiple spot images corresponding to each sub-lens in the following manner: by fitting the grayscale gradient curve of the multiple spot images of each sub-lens, the spot image corresponding to the maximum value of the grayscale gradient curve is used as the focused spot image.

[0107] Furthermore, the fitting of the grayscale gradient curve is to calculate the grayscale gradient curve by derivation of each spot image of each sub-lens cut out, the horizontal axis is the coordinate of the grayscale gradient direction, and the vertical axis is the derivative value of the coordinate grayscale. Exemplarily, the derivation is obtained by convolving the Sobel operator in the horizontal direction and the vertical direction. The Sobel operator is as follows:

[0108]

[0109] in, G x is the Sobel operator in the horizontal direction, G yis the Sobel operator in the vertical direction.

[0110] S22a: Determine the centroid of the light spot in the focused light spot image of each sub-lens.

[0111] If the light spot is a standard circle, then the center of the light spot can be considered as the center of mass of the light spot. However, due to processing issues, the light spot of the sub-lens may not be a standard circle, so the center of mass coordinates of the light spot are selected for linear fitting. In one embodiment of the present invention, the center of mass of the light spot corresponding to the light spot formed by each sub-lens is obtained by the following formula:

[0112]

[0113] in, i and j are the coordinate values ​​of the image in the horizontal and vertical directions respectively. m and n are the number of pixels in two directions respectively, is the gray value at pixel (i, j), x is the coordinate value of the centroid of the light spot in the horizontal direction of the image, y is the coordinate value of the center of mass of the light spot in the longitudinal direction of the image.

[0114] S23a: Perform straight line fitting in the row direction and column direction according to the centroids of the light spots corresponding to all sub-lenses, and obtain fitting straight lines corresponding to each row and each column.

[0115] S24a: Obtain the distance from the centroid of the light spot corresponding to each sub-lens to the fitting straight line corresponding to its row and column as the position deviation of the sub-lens.

[0116] The position deviation includes row deviation and column deviation; according to the position deviation of all sub-lenses, the detection result of the position consistency of the sub-lenses is determined.

[0117] S25a: Determine whether the position deviation of each sub-lens falls within a preset deviation range. If so, the detection result of the position consistency of the sub-lens is qualified; if not, the detection result of the position consistency of the sub-lens is unqualified.

[0118] Assume that the microlens array includes m rows and n columns of sub-lenses, m and n are both greater than 1, and the i-th (1≤i≤m×n) sub-lens is recorded as sub-lens i; determine whether the row deviation and column deviation of sub-lens i both fall within the corresponding preset deviation range; if the row deviation and column deviation of sub-lens i both fall within the corresponding preset deviation range, then determine that the detection result of the position consistency of sub-lens i is qualified; if the row deviation or column deviation of sub-lens i does not fall within the corresponding preset deviation range, then the detection result of the position consistency of sub-lens i is unqualified.

[0119] In one embodiment of the present invention, the detection result of the PSF consistency of the sub-lens is determined by the following method:

[0120] S21b: Acquire a PSF image of each sub-lens, where the PSF image includes an image of a light spot corresponding to the sub-lens.

[0121] S22b: Calculate a corresponding PSF similarity value based on the PSF image of each sub-lens, and / or calculate an area difference between a corresponding light spot and a theoretical light spot based on the PSF image of each sub-lens.

[0122] S23b: Determine the detection result of the PSF consistency of the sub-lens based on the PSF similarity value and / or area difference value corresponding to the sub-lens.

[0123] There are three ways to determine the PSF consistency of a sub-lens:

[0124] Method 1: Only the PSF similarity value is used as the judgment standard for PSF consistency: if the PSF similarity value of a sub-lens reaches a preset PSF similarity threshold, the detection result of the PSF consistency of the sub-lens is qualified.

[0125] Method 2: Only the area difference is used as the judgment standard for PSF consistency: If the area difference between the light spot corresponding to the sub-lens (i.e., the actual light spot) and the theoretical light spot does not exceed the preset area difference threshold, the PSF consistency test result of the sub-lens is qualified.

[0126] Method 3 Figure 3 As shown, in this method, the PSF similarity value and the area difference value are used together as the judgment criteria for PSF consistency: assuming that the microlens array includes m rows and n columns of sub-lenses, m and n are both greater than 1, and the i-th (1≤i≤m×n) sub-lens is recorded as sub-lens i; if the PSF similarity value of sub-lens i reaches a preset PSF similarity threshold, and the area difference between the light spot corresponding to sub-lens i (i.e., the actual light spot) and the theoretical light spot does not exceed the preset area difference threshold, then the PSF of sub-lens i is qualified; if the PSF similarity value of sub-lens i is less than the preset PSF similarity threshold, or the area difference between the light spot corresponding to sub-lens i and the theoretical light spot is greater than the preset area difference threshold, then the detection result of the PSF consistency of sub-lens i is unqualified.

[0127] like Figure 4 As shown, the following describes the determination of whether the sub-lens PSF consistency is qualified or not by using the PSF similarity value as a judgment standard. The PSF image includes an original PSF image and a simulated PSF image, and both the original PSF image and the simulated PSF image include images of the light spots corresponding to the sub-lenses.

[0128] A1: Determine the original PSF image of each sub-lens from multiple spot images of each sub-lens.

[0129] Calculate the gradient values ​​of multiple spot images of each sub-lens; and determine the spot image with the largest gradient value among all the spot images of each sub-lens as the original PSF image of the sub-lens.

[0130] A2: Obtain the simulated PSF image corresponding to each original PSF image.

[0131] The simulated PSF image can be output by optical simulation software such as Zemax.

[0132] A3: Expand the original PSF image of each sub-lens to obtain an expanded PSF image, which is recorded as the expanded PSF image.

[0133] For example, use the following formula to log-expand the original PSF image:

[0134]

[0135] in, I is the normalized grayscale matrix of the original PSF image, I’ is the grayscale matrix of the expanded PSF image, ε and δ are two weighting coefficients.

[0136] For example, taking an 8-bit image as an example, ε and δ The values ​​are 255 and 0.04 respectively. 255 is the maximum grayscale value of an 8-bit image. Here, it is to expand the image in the bottom grayscale area; 0.004 is the result of normalizing the grayscale of an 8-bit image with a grayscale of 1, that is, the value of 1 / 255. Here, it is to ensure that the value in ln is greater than 0.

[0137] A4: Based on the original PSF image, the expanded PSF image and the simulated PSF image, calculate the PSF similarity corresponding to each sub-lens.

[0138] Calculate the similarity value between the original PSF image and the simulated PSF image, recorded as the first similarity value SSIM 1; Calculate the similarity value between the expanded PSF image and the simulated PSF image, recorded as the second similarity value SSIM 2; For the first similarity value SSIM 1 and the second similarity value SSIM 2 Perform weighted summation to obtain the PSF similarity value, that is, use the following formula:

[0139] SSIM 总 =α× SSIM 1+β× SSIM 2

[0140] in, SSIM 总 is the PSF similarity value, α is the weight value of the original PSF image, and β is the weight value of the expanded PSF image.

[0141] A5: If the PSF similarity value of a sub-lens SSIM 总 If the preset PSF similarity threshold is reached, the PSF consistency test result of the sub-lens is qualified.

[0142] Assume that the microlens array includes m rows and n columns of sub-lenses, m and n are both greater than 1, and the i-th (1≤i≤m×n) sub-lens is recorded as sub-lens i; determine whether the PSF similarity value of sub-lens i reaches a preset PSF similarity threshold; if the PSF similarity value of sub-lens i reaches the preset PSF similarity threshold, then determine that the detection result of the PSF consistency of sub-lens i is qualified; if the PSF similarity value of sub-lens i does not reach the preset PSF similarity threshold, then determine that the detection result of the PSF consistency of sub-lens i is unqualified.

[0143] like Figure 5 As shown, the following describes the difference between the area of ​​the actual light spot and the theoretical light spot corresponding to the sub-lens as the judgment standard to determine whether the PSF consistency of the sub-lens is qualified or not:

[0144] B1: Determine the original PSF image of each sub-lens from multiple spot images of each sub-lens.

[0145] The method of obtaining the original PSF image is the same as above and will not be repeated here.

[0146] B2: Determine the area of ​​the light spot in the original PSF image of each sub-lens, and record it as the actual light spot area of ​​each sub-lens.

[0147] B3: Get the theoretical spot area of ​​the sub-lens.

[0148] The theoretical spot area can be obtained through optical simulation software such as Zemax.

[0149] B4: Determine whether the difference between the actual spot area of ​​the sub-lens and the corresponding theoretical spot area is less than a preset area difference threshold.

[0150] B5: If the difference between the actual spot area and the corresponding theoretical spot area is less than the preset area difference threshold, the PSF consistency test result of the sub-lens is considered qualified.

[0151] If the detection result of the PSF consistency of the sub-lens is determined based on the PSF similarity value corresponding to the sub-lens and the area difference value, it is necessary to use the above-mentioned judgment standard to determine whether the PSF similarity value corresponding to the sub-lens meets the PSF consistency standard, and to determine whether the area difference value corresponding to the sub-lens meets the PSF consistency standard. If both standards meet the PSF consistency standard, the detection result of the PSF consistency of the sub-lens is determined to be qualified.

[0152] In one embodiment of the present invention, Figure 6 As shown, the detection result of the MTF consistency of the sub-lens is determined by the following method:

[0153] S21c: Determine an original PSF image of each sub-lens from the multiple spot images of each sub-lens.

[0154] S22c: Perform frequency domain transformation on the original PSF image of each sub-lens to obtain the current MTF image of each sub-lens.

[0155] S23c: Obtain the simulated MTF image of each sub-lens.

[0156] S24c: Calculate the similarity between the current MTF image of each sub-lens and the corresponding simulated MTF image to obtain the MTF similarity value of each sub-lens.

[0157] The following solutions can be adopted:

[0158] C1: Perform multiple synchronous sampling on the same points of the current MTF image and the simulated MTF image to obtain multiple first MTF values ​​and corresponding second MTF values ​​respectively.

[0159] C2: Based on the multiple first MTF values ​​and the corresponding second MTF values, the average value of the MTF similarity values ​​of the sampling points corresponding to the multiple synchronous samplings is calculated, and recorded as the MTF similarity value of each sub-lens.

[0160] The MTF similarity value of the sampling point is related to the ratio of the first MTF value to the second MTF value at the sampling point.

[0161] Furthermore, in one embodiment of the present invention, the MTF similarity value of the sub-lens is calculated using the following formula:

[0162]

[0163] in, P is the MTF similarity value of the sub-lens, For location ( Xi , Yi ), For location ( Xi, Yi ), N is the number of the first MTF value.

[0164] S25c: Determine the detection result of the MTF consistency of the sub-lenses according to the MTF similarity values ​​of all the sub-lenses.

[0165] Assume that the microlens array includes m rows and n columns of sub-lenses, m and n are both greater than 1, and the i-th (1≤i≤m×n) sub-lens is recorded as sub-lens i; determine whether the MTF similarity value of sub-lens i is greater than a preset MTF similarity threshold. If the MTF similarity value of sub-lens i is greater than the preset MTF similarity threshold, the detection result of the MTF consistency of sub-lens i is qualified; if the MTF similarity value of sub-lens i is less than or equal to the preset MTF similarity threshold, the detection result of the MTF consistency of sub-lens i is unqualified.

[0166] In one embodiment of the present invention, a composite MLA detection device for an LED array is provided, such as Figure 7 As shown, the detection device includes a light source 1, a collimator 2, a stage 6, a microscope objective lens 9 and a camera 10 which are sequentially arranged along the vertical light path direction.

[0167] The stage 6 is configured to carry the microlens array 7 to be inspected. The microlens array 7 includes a plurality of sub-lenses arranged in an array. The light emitted by the light source 1 passes through the parallel light tube 2 and is incident on the microlens array 7. The microscope objective 9 is configured to guide the light at the microlens array 7 to the camera 10.

[0168] The detection device also includes a computer 11, which is configured to obtain an array spot image collected by a camera and process the array spot image; to determine a consistency detection result of the sub-lens; wherein the consistency detection result includes at least one of a position consistency detection result, a PSF consistency detection result, and an MTF consistency detection result;

[0169] The computer 11 is further configured to determine a composite MLA detection result of the microlens array based on the consistency detection result of the sub-lenses.

[0170] It is worth noting that the composite MLA detection device for LED arrays provided by the present invention can quantitatively, large-scale and quickly judge the structural quality of the microlens array. By detecting the position, PSF and MTF consistency of the sub-lenses of the microlens array, it can provide feedback on the production process, make timely adjustments to the products in production, improve the yield and reduce quality risks.

[0171] In one embodiment of the present invention, the camera 10 forms an image when the following conditions are met: a star point is provided in the collimator 2, and the light spot formed by focusing after the microlens array 7 is smaller than the diffraction limit of the detection device; the camera 10 is adjusted to the focusing position, and the optical axis distance between the camera 10 and the stage 6 in this state is defined as the reference distance; the camera 10 and / or the stage 6 are moved along the optical axis so that the optical axis distance floats based on the reference distance, and the floating distance is an integer multiple of the depth of focus distance; multiple floatings are performed, and the camera 10 collects the corresponding array light spot image.

[0172] In one embodiment of the present invention, the detection device also includes a Perot plate 3, a horizontal driving mechanism for driving the stage 6 to move in a two-dimensional plane, and a vertical driving mechanism for driving the camera 10 to move along the optical axis direction of the optical path; when the Perot plate 3 is placed in the collimator 2, the horizontal driving mechanism drives the stage 6 to move until the light emitted from the collimator 2 is incident on the microlens array 7; and when the camera 10 is located at the focal plane position under the drive of the vertical driving mechanism, the Perot plate 3 in the collimator 2 is replaced with a star point.

[0173] Exemplarily, the horizontal driving mechanism includes an x-axis precision translation stage 4 and a y-axis precision translation stage 5; a stage 6 is placed on the x-axis precision translation stage 4 and the y-axis precision translation stage 5, and the x-axis precision translation stage 4 and the y-axis precision translation stage 5 are configured to drive the stage 6 to move in a two-dimensional plane. The vertical driving mechanism is a z-axis precision translation stage 8, which is connected to a camera 10, and the z-axis precision translation stage 8 is configured to drive the camera 10 to move along the optical axis direction of the optical path in order to adjust the focus.

[0174] Furthermore, the x-axis precision translation stage 4 , the y-axis precision translation stage 5 , the z-axis precision translation stage 8 and the stage 6 are all hollow-out designs to allow light emitted by the light source 1 to pass through.

[0175] In one embodiment of the present invention, the magnification of the microscope objective 9 is determined by the focal length of the microlens array 7 to be detected, the focal length of the collimator 2 and the pixel size of the camera 10 .

[0176] In one embodiment of the present invention, the light source 1 is monochromatic incoherent light, and the wavelength of the monochromatic incoherent light is determined by the design wavelength of the microlens array 7 to be detected.

[0177] Exemplarily, the detection device of this embodiment implements the composite MLA detection method for LED array provided in the above embodiment, and the detection method includes the following steps:

[0178] S10: Turn on the light source.

[0179] S20: placing the Perot plate in the collimator of the composite MLA detection device.

[0180] S30: Adjust the position of the microlens array on the stage of the composite MLA detection device relative to the collimator so that the light emitted from the collimator is incident on the microlens array, preferably in a vertical incidence mode.

[0181] S40: Adjust the position of the camera of the composite MLA detection device relative to the microlens array on the stage so that the camera is located at the focal plane position.

[0182] S50: Replace the Perot plate in the collimator with a star point accessory, and ensure that the light spot formed by the microlens array back focusing is smaller than the diffraction limit of the composite MLA detection device.

[0183] S60: define the optical axis distance between the current camera and the stage as the reference distance, move the camera and / or the stage along the optical axis so that the optical axis distance floats based on the reference distance, and the floating distance is an integer multiple of the focal depth distance; perform multiple floating operations, and the camera collects a spot image after each floating operation.

[0184] S70: Processing the multiple light spot images to obtain a consistency detection result of the sub-lens.

[0185] The consistency detection result of the sub-lens includes at least one of the sub-lens position consistency, PSF consistency and MTF consistency.

[0186] S80: Determine a composite MLA detection result of the microlens array based on the consistency detection result of the sub-lenses.

[0187] The embodiment of determining the detection results of position consistency, PSF consistency, and MTF consistency in step S70 refers to the above-mentioned embodiment of the composite MLA detection method for LED array, which will not be repeated here.

[0188] In one embodiment of the present invention, multiple spot images are obtained in the following manner: for example, if the focal depth of the system is 10 microns, a spot image is obtained at intervals of 10 microns around the z-axis 0 point, and taking the range of the camera floating up and down at the z-axis 0 point as -100 to 100 microns as an example, a total of 20 images can be obtained; the most focused spot image of each sub-lens is selected from the 20 spot images; wherein, by fitting the grayscale gradient curve of the focused spot image obtained at multiple positions of each sub-lens, the maximum value of the grayscale gradient curve is used as the most focused spot image of the sub-lens. The depth of focus refers to the distance that the focus (focal plane) is allowed to move along the optical axis of the lens while keeping the image relatively clear, and its calculation formula involves wavelength, image space refractive index, and aperture angle of the edge light of the image space.

[0189] In one embodiment of the present invention, correction processing is also included before detection: using a checkerboard to correct the distortion of the camera and the microscope objective 9; collecting a PSF image of the microscope objective 9 to correct the aberration of the microscope objective 9; and performing gamma correction on the camera 10.

[0190] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0191] The above is only a specific implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A composite MLA detection method for LED arrays, characterized in that: The LED array includes a microlens array, and the microlens array includes a plurality of sub-lenses arranged in an array. The detection method includes: Acquire a plurality of light spot images corresponding to each of the sub-lenses; Processing the spot image to determine a consistency detection result of the sub-lens; wherein the consistency detection result includes a PSF consistency detection result, and the consistency detection result also includes at least one of an MTF consistency detection result and a position consistency detection result; Wherein, the detection result of the PSF consistency of the sub-lens is determined by the following method: obtaining a PSF image of each of the sub-lens, the PSF image includes an image of a light spot corresponding to the sub-lens, and the PSF image includes an original PSF image and a simulated PSF image; obtaining the PSF image of each of the sub-lens, including: determining the original PSF image of each sub-lens from a plurality of light spot images of each of the sub-lens; and obtaining a simulated PSF image corresponding to each of the original PSF images; calculating the corresponding PSF similarity value based on the PSF image of each of the sub-lens, and / or, based on the PSF image of each of the sub-lenses, calculating the area difference between the corresponding light spot and the theoretical light spot; based on the PSF similarity value corresponding to the sub-lens and / or the area difference value, determining the detection result of the PSF consistency of the sub-lens, including: expanding the original PSF image of each of the sub-lenses to obtain an expanded PSF image, recorded as an expanded PSF image; based on the original PSF image, the expanded PSF image and the simulated PSF image, calculating the PSF similarity value corresponding to each of the sub-lenses, and then determining the detection result of the PSF consistency of the sub-lens; Based on the consistency detection results of the sub-lenses, a composite MLA detection result of the microlens array is determined.

2. The composite MLA detection method for LED array according to claim 1, characterized in that: The calculating the PSF similarity value corresponding to each sub-lens based on the original PSF image, the expanded PSF image and the simulated PSF image comprises: Calculating a similarity value between the original PSF image and the simulated PSF image, recorded as a first similarity value; Calculating a similarity value between the expanded PSF image and the simulated PSF image, recorded as a second similarity value; A weighted sum is performed on the first similarity value and the second similarity value to obtain the PSF similarity value.

3. The composite MLA detection method for LED array according to claim 1, characterized in that: Determining the original PSF image of each sub-lens from the multiple spot images of each sub-lens includes: calculating the gradient values ​​of the multiple spot images of each sub-lens; determining the spot image with the largest gradient value among all the spot images of each sub-lens as the original PSF image of the sub-lens; And / or, the expanding the original PSF image of each of the sub-lenses includes: performing log expansion on the original PSF image using the following formula: ; Where is the grayscale matrix of the normalized original PSF image, I’ is the grayscale matrix of the expanded PSF image, and are two weighting coefficients.

4. The composite MLA detection method for LED array according to claim 1, characterized in that: The detection result of determining the PSF consistency of the sub-lens based on the area difference corresponding to the sub-lens includes: Determine the area of ​​the light spot in the original PSF image of each sub-lens, and record it as the actual light spot area of ​​each sub-lens; Obtaining a theoretical spot area of ​​the sub-lens; The area difference between the actual spot area and the theoretical spot area of ​​each sub-lens is calculated, and then the detection result of the PSF consistency of the sub-lens is determined.

5. The composite MLA detection method for LED array according to any one of claims 1 to 4, characterized in that: The detection result of determining the PSF consistency of the sub-lens based on the PSF similarity value and / or the area difference value corresponding to the sub-lens includes: If the PSF similarity value corresponding to the sub-lens meets the PSF consistency standard, and the area difference value corresponding to the sub-lens meets the PSF consistency standard, then the PSF consistency detection result of the sub-lens is determined to be qualified.

6. The composite MLA detection method for LED array according to claim 1, characterized in that: The detection result of the MTF consistency of the sub-lens is determined by the following method: Determine an original PSF image of each sub-lens from a plurality of spot images of each sub-lens; Performing frequency domain transformation on the original PSF image of each sub-lens to obtain a current MTF image of each sub-lens; Obtaining simulated MTF images of each sub-lens; The similarity between the current MTF image of each sub-lens and the corresponding simulated MTF image is calculated to obtain the MTF similarity value of each sub-lens, and then determine the detection result of the MTF consistency of the sub-lens.

7. The composite MLA detection method for LED array according to claim 6, characterized in that: The calculating the similarity between the current MTF image and the simulated MTF image of each sub-lens comprises: Performing multiple synchronous sampling on the same points of the current MTF image and the simulated MTF image to obtain multiple first MTF values ​​and corresponding second MTF values ​​respectively; Based on the multiple first MTF values ​​and the corresponding second MTF values, an average value of the MTF similarity values ​​of the sampling points corresponding to the multiple synchronous samplings is calculated, and recorded as the MTF similarity value of each of the sub-lenses, wherein the MTF similarity value of the sampling point is related to the ratio of the first MTF value to the second MTF value at the sampling point; And / or, the detection result of determining the MTF consistency of the sub-lens includes: It is determined whether the MTF similarity value of each of the sub-lenses is greater than a preset MTF similarity threshold value. If so, the detection result of the MTF consistency of the sub-lens is qualified; otherwise, the detection result of the MTF consistency of the sub-lens is unqualified.

8. The composite MLA detection method for LED array according to claim 7, characterized in that: The MTF similarity value of the sub-lens is calculated using the following formula: ； in, P is the MTF similarity value of the sub-lens, For location ( Xi , Yi ), For location ( Xi , Yi ), N is the number of the first MTF value.

9. The composite MLA detection method for LED array according to claim 1, characterized in that: The position consistency of the sub-lenses is determined by: Selecting the most focused spot image from the multiple spot images corresponding to each sub-lens, and recording it as the focused spot image; Determine the centroid of the light spot in the focused light spot image of each sub-lens; According to the centroids of the light spots corresponding to all the sub-lenses, straight line fitting is performed in the row direction and the column direction to obtain the fitting straight lines corresponding to each row and each column; Obtaining the distance from the center of mass of the light spot corresponding to each sub-lens to the fitting straight line corresponding to its row and column as the position deviation of the sub-lens; wherein the position deviation includes row deviation and column deviation; According to the position deviation of each of the sub-lenses, a detection result of the position consistency of the sub-lenses is determined.

10. The composite MLA detection method for an LED array according to claim 9, wherein the step of determining the detection result of the position consistency of the sub-lenses according to the position deviation of each sub-lens comprises: It is determined whether the row deviation and column deviation of each sub-lens are within the corresponding preset deviation range. If so, the detection result of the position consistency of the sub-lens is qualified; otherwise, the detection result of the position consistency of the sub-lens is unqualified.

11. The composite MLA detection method for LED arrays according to any one of claims 1 to 4 or any one of claims 6 to 10, characterized in that: The step of acquiring a plurality of light spot images corresponding to each of the sub-lenses comprises: Acquire a plurality of array spot images, wherein the array spot image includes an image of a spot corresponding to each of the sub-lenses; Performing image clarity calculation on the multiple array light spot images to select a focused array light spot image from the multiple array light spot images; Performing filtering and noise reduction processing on the focused array spot image to obtain a filtered image; Performing circular detection processing on the filtered image to obtain the center coordinates of each light spot in the focusing array light spot image; Each of the array spot images is cropped based on the circle center coordinates to obtain multiple spot images of each sub-lens.

12. The composite MLA detection method for LED arrays according to any one of claims 1 to 4 or any one of claims 6 to 10, characterized in that: The step of determining a composite MLA detection result of the microlens array based on the consistency detection result of the sub-lenses includes: Determine the number of sub-lenses whose PSF consistency test results, MTF consistency test results, and position consistency test results are all qualified; If the number of the qualified sub-lenses in the microlens array reaches a preset ratio threshold, the composite MLA detection result of the microlens array is qualified.

13. A detection device, characterized in that: The device comprises a light source, a collimator, a stage, a microscope objective lens and a camera which are sequentially arranged along the light path direction, wherein the stage is configured to support a microlens array to be detected, wherein the microlens array comprises a plurality of sub-lenses arranged in an array, and the light emitted by the light source passes through the collimator and then enters the microlens array, and the microscope objective lens is configured to guide the light at the microlens array to the camera; The detection device further includes a computer, which is configured to obtain the array spot image collected by the camera and process the array spot image, and the computer is configured to execute the detection method according to any one of claims 1 to 12 to determine the consistency detection result of the sub-lens; wherein the consistency detection result includes a PSF consistency detection result, and the consistency detection result also includes at least one of a position consistency detection result and an MTF consistency detection result; The computer is further configured to determine a composite MLA detection result of the microlens array based on the consistency detection result of the sub-lenses.

14. The detection device according to claim 13 is characterized in that the camera forms an image when the following conditions are met: a star point is used in the collimator, and the light spot formed by focusing after the microlens array is smaller than the diffraction limit of the detection device; the camera is adjusted to a focusing position, and the optical axis distance between the camera and the stage in this state is defined as a reference distance; the camera and / or the stage are moved along the optical axis so that their optical axis distance floats based on the reference distance, and the floating distance is an integer multiple of the depth of focus distance; multiple floatings are performed, and the camera captures corresponding array light spot images.

15. The detection device according to claim 14, characterized in that: The detection device also includes a Perot plate, a horizontal drive mechanism for driving the stage to move in a two-dimensional plane, and a vertical drive mechanism for driving the camera or the stage to move along the optical axis direction of the optical path; When the Perot plate is placed in the collimator, the horizontal driving mechanism drives the stage to move until the light emitted from the collimator is incident on the microlens array; and when the camera is located at the focal plane position under the driving of the vertical driving mechanism, the Perot plate in the collimator is replaced by the star point; And / or, the magnification of the microscope objective lens is determined by the focal length of the microlens array to be detected, the focal length of the collimator, and the pixel size of the camera; And / or, the light source is monochromatic incoherent light, and the wavelength of the monochromatic incoherent light is determined by the design wavelength of the microlens array to be detected.

16. A detection device, characterized in that: The device comprises a light source, a collimator, a stage, a microscope objective lens and a camera which are sequentially arranged along the light path direction, wherein the stage is configured to support a microlens array to be detected, wherein the microlens array comprises a plurality of sub-lenses arranged in an array, and the light emitted by the light source passes through the collimator and then enters the microlens array, and the microscope objective lens is configured to guide the light at the microlens array to the camera; The detection device further comprises a computer configured to execute the detection method according to any one of claims 1 to 12.

Images