A test apparatus, method, device and storage medium for a diffractive optical element

Abstract

Embodiments of the present disclosure provide a test device, method and apparatus for a diffractive optical element, and a storage medium, relating to the technical field of optical testing. The test method for the diffractive optical element comprises: when at a first position, a diffracted light beam emitted by the diffractive optical element enters a transmission screen and forms a diffracted light beam pattern on the transmission screen; an image acquisition device acquires the diffracted light beam pattern to obtain first test information; when at a second position, the diffracted light beam emitted by the diffractive optical element and laser light emitted by a light source enter a light power meter respectively; the light power meter obtains second test information and third test information; and according to the first test information, the second test information and the third test information, a diffractive test result of the diffractive optical element is determined. Through the method, various optical parameters related to the diffractive optical element can be tested, and then various optical performance parameters of the diffractive optical element to be tested are calculated, so that the test and evaluation of the diffractive optical element are realized.

Description

Technical Field

[0001] This disclosure relates to the field of optical testing technology, and in particular to a testing device, method, apparatus, and computer-readable storage medium for a diffractive optical element. Background Technology

[0002] A diffractive optical element (DOE) is a deep-carved structure based on the principle of light diffraction, created by etching two or more steps into the surface of an optical material using microelectronic fabrication techniques. Diffractive optical elements fabricated through optical diffraction can precisely control the light intensity distribution while maintaining high diffraction efficiency, making them ideal for off-axis illumination. Diffractive optical elements are widely used in the laser projection modules of 3D depth cameras. The performance of diffractive optical elements directly affects the quality of the projected pattern, further influencing the depth imaging effect of the depth camera. Therefore, finding an accurate method to test the optical performance of diffractive optical elements is particularly important. Summary of the Invention

[0003] The purpose of this disclosure is to provide a testing device, method, apparatus, and computer-readable storage medium for diffractive optical elements, so as to at least partially solve the technical problems in the related art.

[0004] This disclosure provides a testing apparatus for diffractive optical elements, comprising:

[0005] A light source used to emit laser light;

[0006] A diffractive optical element, disposed opposite to the light source, is used to diffract the laser emitted by the light source;

[0007] A transmission screen is disposed opposite to the diffractive optical element and is used to receive the diffracted beam emitted by the diffractive optical element and form a diffracted beam pattern on the transmission screen.

[0008] An image acquisition device is positioned opposite the transmission screen and is used to acquire the diffraction beam pattern on the transmission screen;

[0009] An optical power meter, disposed opposite to the diffractive optical element, is used to measure the optical power of a light beam incident on the light source or the diffractive optical element;

[0010] The light source and diffractive optical element are fixed on the guide rail and slide along the guide rail to a first position and a second position. When the light source and diffractive optical element slide to the first position, the diffractive optical element is opposite to the transmission screen, so that the diffracted light beam emitted by the diffractive optical element enters the transmission screen. When the light source and diffractive optical element slide to the second position, the diffractive optical element is opposite to the optical power meter, so that the diffracted light beam emitted by the diffractive optical element enters the optical power meter.

[0011] According to another aspect of the embodiments of this disclosure, a method for testing diffractive optical elements is provided, comprising:

[0012] When the light source and the diffractive optical element are in the first position, the diffracted beam emitted by the diffractive optical element enters the transmission screen and forms a diffracted beam pattern on the transmission screen; the image acquisition device acquires the diffracted beam pattern and obtains the first test information;

[0013] When the light source and the diffractive optical element are in the second position, the diffracted beam emitted by the diffractive optical element enters the optical power meter; the optical power meter obtains the second test information;

[0014] When the light source and the diffractive optical element are in the second position, the diffractive optical element is removed, allowing the laser emitted from the light source to enter the optical power meter; the optical power meter obtains third test information;

[0015] Based on the first test information, the second test information, and the third test information, the diffraction test results of the diffraction optical element are determined.

[0016] In some exemplary embodiments of this disclosure, the method further includes:

[0017] The diffraction beam pattern includes a plurality of diffraction spots; the first test information includes: spot position information P of each of the diffraction spots. mn and spot brightness B mn ;

[0018] The second test information includes: the central beam power P C The central beam power P C The optical power of the central beam in the diffraction beam emitted by the diffraction optical element;

[0019] The third test information includes: laser power P i The laser power P i The power of the laser emitted by the light source.

[0020] In some exemplary embodiments of this disclosure, the method further includes:

[0021] Determine the peak position P of each of the diffraction spots. mn_max and peak brightness B mn_max ;

[0022] According to the peak brightness B of the diffraction spot mn_max The selected region of the diffraction spot is determined by a preset selected ratio threshold δ; the spot brightness within the selected region is greater than δ*B. mn_max ;

[0023] Using the major axis of the region to be selected as the diameter D, determine the centroid O of the region to be selected. mn With the centroid O mn Centered on the circle, the circular region defined by the diameter D is the selected region of the diffraction spot;

[0024] The brightness B of the diffraction spot is obtained by integral calculation of the spot brightness based on a selected region of the diffraction spot. mn The centroid O mn The position information P of the diffraction spot mn .

[0025] In some exemplary embodiments of this disclosure, the centroid O of the region to be selected is determined using the major axis of the region to be selected as the diameter D. mn With the centroid O mn Centered on a circle, the circular region defined by the diameter D is the selected region of the diffraction spot, including:

[0026] Using the major axis of the first region to be selected as the first diameter D1, determine the first centroid O of the first region to be selected. mnl ;

[0027] With the first centroid O mn1 Centered on the circle, the circular region defined by the first diameter D1 is the second region to be selected;

[0028] Using the major axis of the second region to be selected as the second diameter D2, determine the second centroid O of the second region to be selected. mn2 ;

[0029] Repeat the above process until the second centroid O is reached. mn2 With the first mass O mn1 The spacing is less than a preset spacing threshold, with the second centroid O mn2 The circular region centered on the second diameter D2 is the selected region of the diffraction spot.

[0030] In some exemplary embodiments of this disclosure, the diffraction test result includes: zero-order light intensity R0; the zero-order light intensity R0 is calculated according to the following formula:

[0031]

[0032] Among them, B 00 B is the brightness of the diffraction spot at the center. mn The brightness of each of the diffraction spots is denoted as .

[0033] In some exemplary embodiments of this disclosure, the diffraction test result includes: spot uniformity U; the spot uniformity U is calculated according to the following formula:

[0034]

[0035] Among them, B max B represents the maximum spot brightness among all the diffraction spots. min The minimum spot brightness among all the diffraction spots.

[0036] In some exemplary embodiments of this disclosure, the diffraction test result includes: diffraction efficiency DE; the diffraction efficiency DE is calculated according to the following formula:

[0037]

[0038] Among them, B 00 B is the brightness of the diffraction spot at the center. mn P represents the brightness of each of the diffraction spots. C P is the optical power of the central beam. i The laser power is denoted as .

[0039] According to another aspect of the embodiments of this disclosure, a testing apparatus for diffractive optical elements is provided, comprising:

[0040] The first test information module is used to acquire the diffraction beam pattern formed by the diffraction beam emitted by the diffraction optical element entering the transmission screen when the light source and the diffraction optical element are in the first position, and obtain the first test information.

[0041] The second test information module is used to obtain second test information of the diffracted beam emitted by the diffracted optical element when the light source and the diffracting optical element are in the second position;

[0042] The third test information module is used to obtain second test information of the laser emitted by the light source when the light source and the diffractive optical element are in the second position;

[0043] The diffraction test result determination module is used to determine the diffraction test result of the diffraction optical element based on the first test information, the second test information, and the third test information.

[0044] According to another aspect of the present disclosure, a computer-readable storage medium is provided storing a computer program adapted to be loaded and executed by a processor to cause a computer device having the processor to perform a test method for any of the diffractive optical elements.

[0045] This disclosure provides a testing method for a diffractive optical element. When the light source and the diffractive optical element are in a first position, the diffracted beam emitted by the diffractive optical element enters a transmission screen and forms a diffracted beam pattern on the screen. An image acquisition device acquires the diffracted beam pattern to obtain first test information. When the light source and the diffractive optical element are in a second position, the diffracted beam emitted by the diffractive optical element enters an optical power meter. The optical power meter obtains second test information. A laser emitted by the light source enters the optical power meter, which then obtains third test information. Based on the first, second, and third test information, the diffraction test result of the diffractive optical element is determined. This testing method for a diffractive optical element allows for efficient and accurate switching between the light source and the diffractive optical element in a first and second position, thereby testing various optical parameters related to the diffractive optical element and calculating various optical performance parameters of the diffractive optical element under test, thus achieving the testing and evaluation of the diffractive optical element.

[0046] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0047] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0048] Figure 1 This is a schematic diagram of the structure of a test apparatus for a diffractive optical element according to an exemplary embodiment;

[0049] Figure 2 This is a flowchart illustrating a test method for a diffractive optical element according to an exemplary embodiment;

[0050] Figure 3 This is a schematic diagram illustrating a diffraction beam pattern according to an exemplary embodiment;

[0051] Figure 4This is a flowchart illustrating an image acquisition device obtaining first test information according to an exemplary embodiment;

[0052] Figure 5 This is a flowchart illustrating the determination of a selected region of a diffraction spot according to an exemplary embodiment;

[0053] Figure 6 This is a schematic diagram illustrating the process of selecting a region of a diffraction spot according to an exemplary embodiment;

[0054] Figure 7 This is a schematic diagram of the structure of a testing apparatus for a diffractive optical element according to an exemplary embodiment;

[0055] Figure 8 This is a schematic diagram illustrating the structure of a computer device suitable for implementing exemplary embodiments of the present disclosure, according to an exemplary embodiment. Detailed Implementation

[0056] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted.

[0057] The features, structures, or characteristics described in this disclosure can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this disclosure. However, those skilled in the art will recognize that the technical solutions of this disclosure can be practiced with one or more specific details omitted, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this disclosure.

[0058] The accompanying drawings are merely illustrative of this disclosure, and the same reference numerals in the drawings denote the same or similar parts, thus omitting repeated descriptions of them. Some block diagrams shown in the drawings do not necessarily correspond to physically or logically independent entities. These functional entities may be implemented in software, in at least one hardware module or integrated circuit, or in different network and / or processor devices and / or microcontroller devices.

[0059] The flowchart shown in the accompanying drawings is merely illustrative and does not necessarily include all content and steps, nor does it require execution in the described order. For example, some steps may be broken down, while others may be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0060] In this specification, the terms “a,” “an,” “the,” “the,” and “at least one” are used to indicate the presence of at least one element / component / etc.; the terms “comprising,” “including,” and “having” are used to indicate an open-ended inclusion and to mean that there may be other elements / components / etc. in addition to the listed elements / components / etc.; the terms “first,” “second,” and “third,” etc., are used only as markings and are not a limitation on the number of objects.

[0061] With the gradual upgrading of the consumer sector, the demand for 3D imaging technology in consumer applications is becoming increasingly urgent. Besides imaging target objects, 3D imaging technology can also acquire depth information of those objects. Based on this depth information, functions such as 3D face recognition, virtual scene modeling, and human-computer interaction can be further realized. At the same time, 3D imaging devices are required to meet the requirements of low power consumption, high performance, and miniaturization, so that they can be incorporated into portable electronic terminal devices.

[0062] Depth cameras (3D cameras) can detect distance information in the shooting space, which is the biggest difference between them and ordinary cameras. Ordinary color cameras capture and record all objects within their field of view, but the recorded data does not include the distances of these objects to the camera. They can only determine which objects are far away and which are near through semantic analysis of the image, without precise data. 3D cameras solve this problem. The data acquired by a 3D camera accurately determines the distance of each point in the image from the camera. Adding this to the two-dimensional coordinates of that point in the 2D image, the three-dimensional spatial coordinates of each point in the image can be obtained. These three-dimensional coordinates can then be used to reconstruct the real scene, enabling applications such as scene modeling.

[0063] Diffractive optical elements (DOEs) are deep-carved structures based on the principle of light diffraction, created by etching two or more steps into the surface of optical materials using microelectronic fabrication techniques. DOE technology enables many functions and light manipulations that are impossible with traditional optical systems. In many applications, these technologies have greatly improved system performance. Diffractive optics offers numerous advantages, such as high efficiency, high precision, small size, low weight, and most importantly, the flexibility to meet diverse application requirements. Due to their unique optical properties, diffractive optical elements have been widely used in the laser projection modules of depth cameras. The performance of diffractive optical elements directly affects the quality of the projected pattern, further influencing the depth imaging effect of the depth camera. Therefore, finding an accurate method to test the optical performance of diffractive optical elements is particularly important.

[0064] Based on this, the present disclosure provides a testing device, method, apparatus, and computer-readable storage medium for diffractive optical elements, which can efficiently and accurately test various optical parameters related to diffractive optical elements, and then calculate various optical performance parameters of the diffractive optical element under test, thereby realizing the testing and evaluation of diffractive optical elements.

[0065] Figure 1 This is a schematic diagram of the structure of a test apparatus for a diffractive optical element according to an exemplary embodiment. Figure 1 As shown, the testing equipment for diffractive optical elements includes:

[0066] Light source 101 is used to emit laser light;

[0067] A diffractive optical element 102 is disposed opposite to the light source 101 and is used to diffract the laser emitted by the light source 101;

[0068] The transmission screen 104 is disposed opposite to the diffractive optical element 102 and is used to receive the diffracted beam emitted by the diffractive optical element 102 and form a diffracted beam pattern on the transmission screen 104.

[0069] The image acquisition device 105 is positioned opposite to the transmission screen 104 and is used to acquire the diffraction beam pattern on the transmission screen 104.

[0070] An optical power meter 106 is disposed opposite to a diffractive optical element 102 and is used to measure the optical power of a light beam incident from a light source 101 or a diffractive optical element 102.

[0071] The light source 101 and the diffractive optical element 102 are fixed on the guide rail 103 and slide along the guide rail 103 to a first position and a second position. When the light source 101 and the diffractive optical element 102 slide to the first position, the diffractive optical element 102 is opposite to the transmission screen 104, so that the diffracted beam emitted by the diffractive optical element 102 enters the transmission screen 104. When the light source 101 and the diffractive optical element 102 slide to the second position, the diffractive optical element 102 is opposite to the optical power meter 106, so that the diffracted beam emitted by the diffractive optical element 102 enters the optical power meter 106.

[0072] In this embodiment, the light source 101 is a side-emitting semiconductor laser, and its emitted light is a laser beam with a circular Gaussian spot after beam shaping and collimation. The diffractive optical element 102 is the diffractive optical element to be tested. The diffractive optical element 102 is perpendicular to the emitted light direction of the light source 101, so that the laser emitted from the light source 101 is perpendicularly incident on the diffractive optical element 102, and after diffraction by the diffractive optical element 102, a diffracted beam is formed and emitted.

[0073] Due to optical requirements, the distance between the light source 101 and the diffractive optical element 102 should not be too large; otherwise, effective optical diffraction cannot be formed. Generally, the distance between the light source 101 and the diffractive optical element 102 should be less than 5 mm. It should be noted that the distance between the light source and the diffractive optical element described above is only used to illustrate one specific embodiment of this disclosure and is not intended to limit the scope of protection of this disclosure.

[0074] In this embodiment, the light source 101 and the diffractive optical element 102 are fixed on the guide rail 103 and slide along the guide rail 103 to a first position and a second position. During the sliding process, the relative position between the light source 101 and the diffractive optical element 102 remains unchanged to ensure that the optical parameters tested at both the first and second positions remain consistent.

[0075] The first position is the pattern acquisition area. In the first position, the diffractive optical element 102 is positioned opposite to the transmission screen 104. The image acquisition device 105 and the diffractive optical element 102 are located on opposite sides of the transmission screen 104. The diffracted beam emitted from the diffractive optical element 102 enters the transmission screen 104 and forms a diffracted beam pattern on the transmission screen 104. The image acquisition device 105, located on the other side of the transmission screen 104, acquires an image of this diffracted beam pattern.

[0076] In an exemplary embodiment, the light source 101, the diffractive optical element 102, the transmission screen 104, and the image acquisition device 105 are in a coaxial state. This ensures that neither the diffraction beam pattern formed on the transmission screen 104 nor the image acquisition of the diffraction beam pattern by the image acquisition device 105 will introduce additional distortion due to angular offset, thus preventing errors in the final tested optical parameters.

[0077] The second position is the optical power measurement area. In the second position, the diffractive optical element 102 is positioned opposite to the optical power meter 106. The diffracted beam emitted from the diffractive optical element 102 and the laser emitted from the light source 101 are respectively incident on the optical power meter 106. The optical power meter 106 is typically a silicon-based optical power meter used to measure the optical power of the incident beam. Since optical power meters are commonly used optical measuring instruments, their structure and measurement principle will not be further limited here. It should be considered that any optical instrument known to those skilled in the art for measuring optical power can be used as the optical power meter described above in this disclosure.

[0078] In an exemplary embodiment, the light source 101, the diffractive optical element 102, and the optical power meter 106 are coaxial. Thus, by simply removing the diffractive optical element 102, the optical power meter 106 can switch between measuring the diffracted beam emitted by the diffractive optical element 102 and the laser emitted by the light source 101. Fewer operation steps ensure the accuracy of the relevant measurement parameters. Simultaneously, based on this state setting, the optical power meter 106 only measures the central beam of the diffracted beam emitted by the diffractive optical element 102. Based on the image acquisition of the diffracted beam pattern by the aforementioned image acquisition device 105 and the measurement of the central beam, the relevant optical parameters of the other diffracted beams can be calculated. Therefore, the optical power meter 106 does not need to measure each diffracted beam separately, further reducing the complexity of the test and improving the accuracy of the final test results. It should be noted that the optical power meter 106 can also measure other non-central diffractive beams emitted by the diffractive optical element 102, and then calculate the relevant optical parameters of other diffractive beams based on the image acquisition of the diffractive beam pattern by the aforementioned image acquisition device 105, which will not be elaborated here.

[0079] In this embodiment, when in the first position, the distance between the diffractive optical element 102 and the transmission screen 104 is a first distance. When in the second position, the distance between the diffractive optical element 102 and the optical power meter 106 is a second distance. The first distance and the second distance are equal. Since the testing equipment for the diffractive optical element provided in this disclosure needs to calculate the various optical performance parameters of the diffractive optical element under test using the optical parameters collected at the first and second positions respectively, placing the transmission screen 104 and the optical power meter 106 at the same distance from the diffractive optical element 102 avoids introducing relative errors and ensures that the diffractive beam pattern and optical power are obtained in the same state.

[0080] In this embodiment, the transmission screen 104 must both transmit the diffracted light beam so that the image acquisition device 105 can collect the transmitted diffracted light beam, and form a clear diffracted light beam pattern on it. Therefore, the transmission screen 104 needs to be made of a light-transmitting planar material with uniform transmittance and diffuse reflection greater than 50%. In a specific embodiment, the transmission screen 104 can be made by laying white paper, photographic paper, or other materials with a certain transmittance on a glass plate.

[0081] In this embodiment, the image acquisition device 105 includes a lens and an image sensor. By adjusting the distance between the image acquisition device 105 and the transmission screen 104, the image acquisition device 105 can acquire the complete diffraction beam pattern on the transmission screen 104. Furthermore, the image acquisition device 105 can also be connected to a computing device to transmit the acquired diffraction beam pattern to the computing device for calculating relevant optical parameters.

[0082] The testing equipment for diffractive optical elements provided in this disclosure includes: a light source for emitting laser light; a diffractive optical element for diffracting the laser light emitted by the light source; a transmission screen for receiving the diffracted beam emitted by the diffractive optical element and forming a diffracted beam pattern; an image acquisition device for acquiring the diffracted beam pattern; and an optical power meter for measuring the optical power of the beam incident by the light source or the diffractive optical element. The light source and the diffractive optical element are fixed on a guide rail and slide along the guide rail to a first position and a second position. In the first position, the diffractive optical element is opposite to the transmission screen; in the second position, the diffractive optical element is opposite to the optical power meter. The testing equipment for diffractive optical elements provided in this disclosure can efficiently and accurately switch the light source and the diffractive optical element between the first and second positions, thereby testing various optical parameters related to the diffractive optical element, and then calculating various optical performance parameters of the diffractive optical element under test, thus realizing the testing and evaluation of the diffractive optical element.

[0083] Figure 2This is a flowchart illustrating a testing method for a diffractive optical element according to an exemplary embodiment. The method provided in this disclosure can be based on... Figure 1 The test equipment for the diffractive optical element in the embodiment is performed.

[0084] like Figure 2 As shown, the testing method for diffractive optical elements provided in this disclosure includes:

[0085] In step S210, when the light source and the diffractive optical element are in the first position, the diffractive beam emitted by the diffractive optical element enters the transmission screen and forms a diffractive beam pattern on the transmission screen; the image acquisition device acquires the diffractive beam pattern and obtains the first test information.

[0086] In this embodiment, the first position is a pattern acquisition area. At the first position, the diffractive optical element is positioned opposite to the transmission screen. Laser light emitted from the light source is incident perpendicularly on the diffractive optical element, and after diffraction, forms a diffracted beam that exits. The diffracted beam emitted from the diffractive optical element enters the transmission screen and forms a diffracted beam pattern on the screen. An image acquisition device, located on the other side of the transmission screen, acquires an image of the diffracted beam pattern and obtains first test information based on the acquired diffracted beam pattern.

[0087] In this embodiment of the present disclosure, the laser emitted from the light source is diffracted by the diffractive optical element and dispersed into several diffracted beams. Figure 3 This is a schematic diagram illustrating a diffraction beam pattern according to an exemplary embodiment. Figure 3 As shown, these diffracted beams illuminate the transmission screen, forming a diffracted beam pattern consisting of several diffracted spots arranged in an array. The center of this diffracted spot array is located at (…). Figure 3 The area circled in the center (the position of the diffraction beam) represents the diffraction spot formed by the center beam in the diffraction beam. The first test information includes: the spot position information P of each diffraction spot. mn and spot brightness B mn In this system, the array of diffracted light spots is used as the coordinate system, where m represents the horizontal axis and n represents the vertical axis. The light spot position information P... mn This represents the position information of the diffraction spot at coordinates (m,n). The spot brightness B... mn , representing the brightness information of the diffraction spot with coordinates (m,n).

[0088] In an exemplary embodiment, Figure 3The diffraction beam pattern shown is a 9x11 array of diffraction spots, containing 99 spots. A coordinate system is established based on this array, with the origin (0,0) at the center diffraction spot. The x-coordinate m ranges from [-4,4], and the y-coordinate n ranges from [-5,5]. As shown in the figure, the coordinates of the diffraction spot in the upper right corner of the array are (4,5), and its position information P... 45 Its spot brightness B 45 Similarly, the diffraction spot coordinates at the lower corner of this spot array are (-4, -5), and its spot position information P -4-5 Its spot brightness B -4-5 The above examples are for illustrative purposes only and are not intended to limit the scope of this disclosure.

[0089] In step S220, when the light source and the diffractive optical element are in the second position, the diffracted beam emitted by the diffractive optical element enters the optical power meter; the optical power meter obtains the second test information.

[0090] In this embodiment, the second position is an optical power measurement region. In the second position, the diffractive optical element and the optical power meter are positioned opposite each other. Laser light emitted from the light source is incident perpendicularly to the diffractive optical element, and after diffraction, a diffracted beam is formed and emitted. The diffracted beam emitted from the diffractive optical element enters the optical power meter. This optical power meter is used to measure the optical power of the incident beam. Second test information is obtained by measuring the diffracted beam using this optical power meter.

[0091] In an exemplary embodiment, the optical power meter measures only the central beam of the diffracted beam emitted from the diffracting optical element and obtains second test information about that central beam. The second test information includes: the optical power P of the central beam. C The central beam power P C The optical power of the central beam in the diffraction beam emitted by the diffraction optical element.

[0092] In step S230, when the light source and the diffractive optical element are in the second position, the diffractive optical element is removed, allowing the laser emitted from the light source to enter the optical power meter; the optical power meter obtains third test information.

[0093] In this embodiment, the second position is an optical power measurement area. In the second position, after removing the diffractive optical element, the light source and the optical power meter are positioned opposite each other. Laser light emitted from the light source enters the optical power meter. This optical power meter is used to measure the optical power of the incident beam. Third test information is obtained by measuring the laser light using this optical power meter. The third test information includes: laser optical power P. i The laser power P iThe power of the laser emitted by the light source.

[0094] Step S240: Determine the diffraction test result of the diffraction optical element based on the first test information, the second test information, and the third test information.

[0095] In this embodiment of the disclosure, based on the first test information, second test information, and third test information obtained from the above tests, various optical performance parameters of the diffractive optical element under test can be calculated as diffraction test results. These diffraction test results may include one or more combinations of zero-order intensity R0, spot uniformity U, and diffraction efficiency DE. Wherein, zero-order intensity R0 represents the ratio of the brightness of the central beam spot to the sum of the brightness of all diffracted spots. Spot uniformity U measures the brightness uniformity of each diffracted spot among all diffracted spots. Diffraction efficiency DE refers to the ratio of the total intensity of the diffracted beam emitted from the diffractive optical element to the intensity of the laser beam incident on the diffractive optical element.

[0096] It should be noted that the above only provides optical performance parameters for a few diffractive optical elements under test as examples. Those skilled in the art, based on actual testing needs, can calculate the optical performance parameters of the diffractive optical element under test using the first, second, and third test information obtained by the above method, and based on known calculation methods in the prior art. All such calculations should be considered within the scope of protection of this disclosure.

[0097] Furthermore, although steps S210, S220, and S230 are described in sequential numbering, in actual testing, personnel can arbitrarily arrange the testing order of the first, second, and third test information according to actual needs. This disclosure does not limit the relevant testing order.

[0098] The testing method for diffractive optical elements provided in this disclosure includes: in a first position, a diffracted beam emitted by the diffractive optical element is incident on a transmission screen, forming a diffracted beam pattern on the transmission screen; an image acquisition device acquires the diffracted beam pattern to obtain first test information; in a second position, diffracted beams and lasers emitted by the diffractive optical element and the light source, respectively, are incident on an optical power meter; second test information and third test information are obtained; and the diffraction test result of the diffractive optical element is determined based on the first test information, the second test information, and the third test information. The testing method for diffractive optical elements provided in this disclosure can efficiently and accurately switch between the light source and the diffractive optical element in a first and second position, thereby testing various optical parameters related to the diffractive optical element, and then calculating various optical performance parameters of the diffractive optical element under test, thus realizing the testing and evaluation of the diffractive optical element.

[0099] In this embodiment of the disclosure, the testing method for diffractive optical elements further includes adjusting the spacing between the diffractive optical element, the transmission screen, and the image acquisition device. Adjusting the spacing between these components ensures that the image acquisition device can capture the complete diffraction beam pattern on the transmission screen. It should be noted that this spacing adjustment step can adjust the spacing between all three components, or it can adjust the spacing between any two of them. The key is to ensure that the image acquisition device can capture the complete diffraction beam pattern on the transmission screen.

[0100] Figure 4 This is a flowchart illustrating an image acquisition device obtaining first test information according to an exemplary embodiment. For example... Figure 4 As shown, step S210 further includes:

[0101] Step S211: Determine the peak position P of each of the diffraction spots. mn_max and peak brightness B mn_max ;

[0102] In this embodiment of the disclosure, each diffraction spot in the diffraction pattern is independently subjected to corresponding first test information acquisition. For the diffraction spot with coordinates (m,n), the brightness peak point within the range of the diffraction spot is determined, and the peak position P of the brightness peak point is determined. mn_max and peak brightness B mn_max .

[0103] Step S212, based on the peak brightness B of the diffraction spot mn_max The selected region of the diffraction spot is determined by a preset selected ratio threshold δ; the spot brightness within the selected region is greater than δ*B. mn_max ;

[0104] In this embodiment, we perform binarization processing on each diffraction spot based on brightness. Based on a preset selected ratio threshold δ, the brightness threshold for the binarization processing of the diffraction spot is calculated as δ*B. mn_max The selected proportional threshold δ is a proportional value, where the brightness within the diffraction spot range is greater than the brightness threshold δ*B. mn_max The portion is designated as the area to be selected.

[0105] In an exemplary embodiment, we set the selected proportion threshold δ to 13.5%. That is, the brightness within the diffraction spot range is greater than 13.5%B. mn_max The portion is designated as the area to be selected, with peak brightness B. mn_maxFor example, if the brightness of the diffraction spot is greater than 13.5, the part within the diffraction spot range is considered as the selected area; otherwise, the part within the diffraction spot range with a brightness of less than 13.5 is not considered as the selected area.

[0106] Step S213: Using the major axis of the region to be selected as the diameter D, determine the centroid O of the region to be selected. mn With the centroid O mn Centered on the circle, the circular region defined by the diameter D is the selected region of the diffraction spot;

[0107] In this embodiment, because the brightness distribution within the diffraction spot is not uniform, the region to be selected determined in step S212 is not necessarily a regular image. Step S213 involves adjusting the region to be selected based on the region determined in step S212, making the selected region a circular area. The specific steps for determining the selected region are as follows:

[0108] First, determine the major axis within the selected region, and use the peak position P. mn_max The first circular region is defined with the major axis as the center and the diameter D as the diameter of the circle.

[0109] Second, determine the centroid O of the first circular region. mn ;

[0110] Third, with the centroid O mn Centered on the circle, the circular region defined by the diameter D is the selected region of the diffraction spot.

[0111] It should be noted that the centroid of the light spot is determined based on the brightness distribution of each pixel within the spot, using these distributions as weights. Since the brightness distribution within the spot is not uniform, this centroid location is not necessarily the center of the circle. As the algorithm for determining the centroid of the light spot is common knowledge in this field, it will not be elaborated upon here.

[0112] Step S214: Perform spot brightness integral calculation based on the selected region of the diffraction spot to obtain the spot brightness B of the diffraction spot. mn The centroid O mn The position information P of the diffraction spot mn .

[0113] In this embodiment of the disclosure, based on the selected area determined in step S213, the brightness of each pixel within the selected area is integrated to obtain the sum of the brightness values ​​of each pixel within the selected area, which is used as the brightness B of the diffraction spot. mn The centroid O determined in step S213 mn The position information P of the diffraction spotm .

[0114] The first test information acquisition process provided in this embodiment can preprocess each spot in the diffraction beam pattern, determine the selected area of ​​each diffraction spot through a consistent preprocessing method, and obtain the first test information of each diffraction spot based on the selected area, ensuring that the first test information between each diffraction spot is comparable, and providing a data basis for subsequent calculation of the optical performance parameters of the diffraction optical element and comparison of the optical parameters between each diffraction spot.

[0115] Figure 5 This is a flowchart illustrating the determination of a selected region of a diffraction spot according to an exemplary embodiment. Figure 6 This is a schematic diagram illustrating the selection process of a selected region for a diffraction spot according to an exemplary embodiment. Figure 5 , Figure 6 As shown, step S213 further includes:

[0116] Step S213a: Using the major axis of the first region to be selected as the first diameter D1, determine the first centroid O of the first region to be selected. mn1 ;

[0117] In this embodiment of the disclosure, based on the method described in step S213 above, the first diameter D1 and the first centroid O of the first region to be selected are obtained. mn1 Since the specific method for obtaining the result has already been described in step S213 above, it will not be repeated here.

[0118] Step S213b, with the first centroid O mn1 Centered on the circle, the circular region defined by the first diameter D1 is the second region to be selected;

[0119] In this embodiment of the disclosure, the first diameter D1 and the first centroid O of the first region to be selected are determined based on step S213a. mn1 With the first mass center O mn1 Centered on the circle, the circular region defined by the first diameter D1 is the second region to be selected.

[0120] Step S213c: Using the major axis of the second region to be selected as the second diameter D2, determine the second centroid O of the second region to be selected. mn2 ;

[0121] In this embodiment of the disclosure, based on the method described in step S213 above, the second diameter D2 and the second centroid O of the second region to be selected are obtained. mn2 Since the specific method for obtaining the result has already been described in step S213 above, it will not be repeated here.

[0122] Step S213d: Repeat the above process until the second centroid O is reached. mn2 With the first mass O mn1 The spacing is less than a preset spacing threshold, with the second centroid O mn2 The circular region centered on the second diameter D2 is the selected region of the diffraction spot.

[0123] In this embodiment, since the brightness distribution within the diffraction spot is not uniform, a stable and ideal selected area range may not be obtained simply by completing the selected area determination process described in step S213 once. To optimize this determination process and obtain a stable and ideal selected area, this embodiment continuously repeats the selected area determination process until the centroid distance between two consecutive determinations is less than a preset distance threshold. In one feasible implementation, the preset distance threshold is set to 0.5 pixels.

[0124] This method, through repeated calculations of the centroid position of the selected region, yields a more stable final selection area. The initial test information calculated based on this selected region is also more accurate. This provides a data foundation for more accurately calculating the various optical performance parameters of the diffractive optical element under test.

[0125] In this embodiment of the disclosure, step S240, which determines the diffraction test result of the diffraction optical element based on the first test information, the second test information, and the third test information, further includes:

[0126] The diffraction test results include: zero-order light intensity R0; the zero-order light intensity R0 is calculated according to the following formula (1):

[0127]

[0128] Among them, B 00 B is the brightness of the diffraction spot at the center. mn The brightness of each of the diffraction spots is denoted as .

[0129] The first test information obtained according to the aforementioned step S210 includes: the spot position information P of each diffraction spot. mn and spot brightness B mn Based on the first test information, the zero-order light intensity R0 can be calculated using the above formula (1). This zero-order light intensity R0 represents the ratio of the brightness of the central beam spot to the sum of the brightness of all diffracted beam spots.

[0130] In this embodiment of the disclosure, step S240, which determines the diffraction test result of the diffraction optical element based on the first test information, the second test information, and the third test information, further includes:

[0131] The diffraction test results include: spot uniformity U; the spot uniformity U is calculated according to the following formula (2):

[0132]

[0133] Among them, B max B represents the maximum spot brightness among all the diffraction spots. min The minimum spot brightness among all the diffraction spots.

[0134] The first test information obtained according to the aforementioned step S210 includes: the spot position information P of each diffraction spot. mn and spot brightness B mn Based on the first test information, the spot uniformity U can be calculated using the above formula (2). This spot uniformity U is used to measure the brightness uniformity of each diffraction spot in the entire diffraction pattern.

[0135] In this embodiment of the disclosure, step S240, which determines the diffraction test result of the diffraction optical element based on the first test information, the second test information, and the third test information, further includes:

[0136] The diffraction test results include: diffraction efficiency DE; the diffraction efficiency DE is calculated according to the following formula (3):

[0137]

[0138] Among them, B 00 B is the brightness of the diffraction spot at the center. mn P represents the brightness of each of the diffraction spots. C P represents the optical power of the central beam. i This refers to the laser power.

[0139] The first test information, the second test information, and the third test information are obtained according to the aforementioned steps S210, S220, and S230, including: the spot position information P of each diffraction spot. mn and spot brightness B mn The central beam power P of the diffractive optical element C The laser power P of the light source i Based on the above test information, the diffraction efficiency DE can be calculated using the above formula (3). The diffraction efficiency DE refers to the ratio of the total intensity of the diffracted beam emitted by the diffracting optical element to the intensity of the laser beam incident on the diffracting optical element. The diffraction efficiency DE reflects the diffraction effect of the diffracting optical element. The higher the diffraction efficiency, the lower the power consumption requirement of the light source for generating the same intensity diffracted beam pattern.

[0140] Figure 7 This is a schematic diagram of a testing apparatus for a diffractive optical element according to an exemplary embodiment. Figure 7 As shown, the testing apparatus 700 for the diffractive optical element includes:

[0141] The first test information module 710 is used to acquire the diffraction beam pattern formed by the diffraction beam emitted by the diffraction optical element entering the transmission screen when the light source and the diffraction optical element are in the first position, and obtain the first test information.

[0142] The second test information module 720 is used to obtain second test information of the diffracted beam emitted by the diffracted optical element when the light source and the diffracting optical element are in the second position;

[0143] The third test information module 730 is used to obtain second test information of the laser emitted by the light source when the light source and the diffractive optical element are in the second position;

[0144] The diffraction test result determination module 740 is used to determine the diffraction test result of the diffraction optical element based on the first test information, the second test information, and the third test information.

[0145] The testing apparatus 700 for the diffractive optical element obtains first test information in a first position via a first test information module 710; and obtains second and third test information via a second test information module 720 and a third test information module 730, respectively, when the diffracted beams and laser emitted by the diffractive optical element and the light source are incident on an optical power meter in a second position. The diffraction test result determination module 740 determines the diffraction test result of the diffractive optical element based on the first, second, and third test information. The testing apparatus for the diffractive optical element provided in this embodiment can efficiently and accurately switch between the light source and the diffractive optical element in a first and second position, thereby testing various optical parameters related to the diffractive optical element and calculating various optical performance parameters of the diffractive optical element under test, thus achieving the testing and evaluation of the diffractive optical element.

[0146] In this embodiment of the disclosure, the diffraction beam pattern includes a plurality of diffraction spots; the first test information includes: spot position information P of each of the diffraction spots. mn and spot brightness B mn The second test information includes: the central beam optical power P. C The central beam power P C The optical power of the central beam in the diffraction beam emitted by the diffraction optical element; the third test information includes: laser optical power P i The laser power P iThe power of the laser emitted by the light source.

[0147] In this embodiment of the disclosure, the first test information module 710 is further configured to determine the peak position P of each of the diffraction spots. mn_max and peak brightness B mn_max According to the peak brightness B of the diffraction spot mn_max The selected region of the diffraction spot is determined by a preset selected ratio threshold δ; the spot brightness within the selected region is greater than δ*B. mn_max Using the major axis of the region to be selected as the diameter D, determine the centroid O of the region to be selected. mn With the centroid O mn Centered on a circle, a circular region defined by the diameter D is selected as the region of the diffraction spot; the spot brightness B is calculated by integrating the brightness of the diffraction spot based on the selected region. mn The centroid O mn The position information P of the diffraction spot mn .

[0148] In this embodiment of the disclosure, the first test information module 710 is further configured to determine the first centroid O of the first region to be selected, using the major axis of the first region to be selected as the first diameter D1. mn1 With the first centroid O mn1 Using the first diameter D1 as the center, the circular region defined by the first diameter D1 is taken as the second region to be selected; using the major axis of the second region to be selected as the second diameter D2, the second centroid O of the second region to be selected is determined. mn2 Repeat the above process until the second centroid O is reached. mn2 With the first mass O mn1 The spacing is less than a preset spacing threshold, with the second centroid O mn2 The circular region centered on the second diameter D2 is the selected region of the diffraction spot.

[0149] In this embodiment of the disclosure, the diffraction test result determination module 740 is further used to determine the diffraction test result, including: zero-order light intensity R0; the zero-order light intensity R0 is calculated according to the following formula:

[0150]

[0151] Among them, B 00 B is the brightness of the diffraction spot at the center. mn The brightness of each of the diffraction spots is denoted as .

[0152] In this embodiment of the disclosure, the diffraction test result determination module 740 is further used to determine the diffraction test result, including: spot uniformity U; the spot uniformity U is calculated according to the following formula:

[0153]

[0154] Among them, B max B represents the maximum spot brightness among all the diffraction spots. min The minimum spot brightness among all the diffraction spots.

[0155] In this embodiment of the disclosure, the diffraction test result determination module 740 is further configured to determine the diffraction test result, including: diffraction efficiency DE; the diffraction efficiency DE is calculated according to the following formula:

[0156]

[0157] Among them, B 00 B is the brightness of the diffraction spot at the center. mn P represents the brightness of each of the diffraction spots. C P is the optical power of the central beam. i The laser power is denoted as .

[0158] It should be noted that the testing apparatus for the diffractive optical element is an apparatus for implementing the aforementioned testing method for the diffractive optical element. Therefore, the apparatus inherits the relevant embodiments described in the above method during implementation, and will not be repeated here.

[0159] Figure 8 This is a schematic diagram illustrating the structure of a computer device suitable for implementing exemplary embodiments of the present disclosure, according to an exemplary embodiment.

[0160] like Figure 8 As shown, the computer device in this embodiment may include one or more processors 801, a memory 802, and an input / output interface 803. The processor 801, memory 802, and input / output interface 803 are connected via a bus 804. The memory 802 stores a computer program, which includes program instructions. The input / output interface 803 receives and outputs data, such as for data interaction between the host machine and the computer device, or for data interaction between various virtual machines within the host machine. The processor 801 executes the program instructions stored in the memory 802.

[0161] The processor 801 can perform the following operations:

[0162] When the light source and the diffractive optical element are in the first position, the diffracted beam emitted by the diffractive optical element enters the transmission screen and forms a diffracted beam pattern on the transmission screen; the image acquisition device acquires the diffracted beam pattern and obtains the first test information;

[0163] When the light source and the diffractive optical element are in the second position, the diffracted beam emitted by the diffractive optical element enters the optical power meter; the optical power meter obtains the second test information;

[0164] When the light source and the diffractive optical element are in the second position, the diffractive optical element is removed, allowing the laser emitted from the light source to enter the optical power meter; the optical power meter obtains third test information;

[0165] Based on the first test information, the second test information, and the third test information, the diffraction test results of the diffraction optical element are determined.

[0166] In some feasible implementations, the processor 801 may be a central processing unit (CPU), but it can also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0167] The memory 802 may include read-only memory and random access memory, and provides instructions and data to the processor 801 and the input / output interface 803. A portion of the memory 802 may also include non-volatile random access memory. For example, the memory 802 may also store device type information.

[0168] In practice, the computer device can execute the implementation methods provided by the steps in the above embodiments through its built-in functional modules. For details, please refer to the implementation methods provided by the steps in the above embodiments, which will not be repeated here.

[0169] This disclosure provides a computer device including a processor, an input / output interface, and a memory. The processor retrieves a computer program from the memory and executes the steps of the method shown in the above embodiments to perform a transmission operation.

[0170] This disclosure also provides a computer-readable storage medium storing a computer program adapted to be loaded by a processor and execute the methods provided in the steps of the above embodiments. Specific implementations of the steps in the above embodiments can be found therein and will not be repeated here. Furthermore, the beneficial effects of using the same method will not be repeated here either. For technical details not disclosed in the embodiments of the computer-readable storage medium involved in this disclosure, please refer to the description of the method embodiments of this disclosure. As an example, the computer program can be deployed to execute on a single computer device, or on multiple computer devices located in one location, or on multiple computer devices distributed across multiple locations and interconnected via a communication network.

[0171] The computer-readable storage medium can be the apparatus provided in any of the foregoing embodiments or the internal storage unit of the computer device, such as the hard disk or memory of the computer device. The computer-readable storage medium can also be an external storage device of the computer device, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc., provided on the computer device. Furthermore, the computer-readable storage medium can include both internal storage units and external storage devices of the computer device. The computer-readable storage medium is used to store the computer program and other programs and data required by the computer device. The computer-readable storage medium can also be used to temporarily store data that has been output or will be output.

[0172] This disclosure also provides a computer program product or computer program that includes computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the methods provided in the various alternative embodiments described above.

[0173] The terms "first," "second," etc., used in the specification, claims, and drawings of this disclosure are used to distinguish different objects, not to describe a specific order. Furthermore, the term "comprising," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, apparatus, product, or device that includes a series of steps or units is not limited to the listed steps or modules, but may optionally include steps or modules not listed, or may optionally include other step units inherent to these processes, methods, apparatuses, products, or devices.

[0174] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of each example have been generally described in terms of functionality. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this disclosure.

[0175] The methods and related apparatuses provided in this disclosure are described with reference to the method flowcharts and / or structural diagrams provided in this disclosure. Specifically, each block of the method flowchart and / or structural diagram, as well as combinations of blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions are provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable transmission device to create a machine, such that the instructions, which execute via the processor of the computer or other programmable transmission device, generate instructions for implementing the process. Figure 1 A schematic diagram of one or more processes and / or structures. Figure 1 The computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable transmission device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 A schematic diagram of one or more processes and / or structures. Figure 1 The functions specified in one or more boxes. These computer program instructions may also be loaded onto a computer or other programmable transmission device to cause a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable device for implementing the process. Figure 1 A process or multiple processes and / or structures illustrate the steps of the functions specified in one or more boxes.

[0176] The above-disclosed embodiments are merely preferred embodiments of this disclosure and should not be construed as limiting the scope of this disclosure. Therefore, any equivalent variations made in accordance with the claims of this disclosure shall still fall within the scope of this disclosure.

Claims

1. A method for testing diffractive optical elements, characterized in that, The testing method includes: When the light source and the diffractive optical element are located at the first position, the diffractive optical element emits a diffractive light beam into the transmission screen and forms a diffractive light beam pattern on the transmission screen; an image acquisition device acquires the diffractive light beam pattern to obtain first test information; the diffractive light beam pattern includes a plurality of diffractive light spots; the first test information includes: spot position information P of each of the diffractive light spots mn and spot brightness B mn ; When the light source and the diffractive optical element are in the second position, the diffracted beam emitted by the diffractive optical element enters the optical power meter; the optical power meter obtains second test information; the second test information includes: the optical power P of the central beam. C The central beam power P C The optical power of the central beam in the diffraction beam emitted by the diffraction optical element; When the light source and diffractive optical element are in the second position, the diffractive optical element is removed, allowing the laser emitted from the light source to enter the optical power meter; the optical power meter obtains third test information; the third test information includes: laser optical power P i The laser power P i The light power of the laser emitted by the light source; Based on the first test information, the second test information, and the third test information, the diffraction test results of the diffraction optical element are determined; The image acquisition device acquires the diffraction beam pattern to obtain first test information, including: Determine the peak position P of each of the diffraction spots. mn_max and peak brightness B mn_max ; According to the peak brightness B of the diffraction spot mn_max The selected region of the diffraction spot is determined by a preset selected ratio threshold δ; the spot brightness within the selected region is greater than δ. B mn_max ; Using the major axis of the region to be selected as the diameter D, determine the centroid O of the region to be selected. mn With the centroid O mn Centered on the circle, the circular region defined by the diameter D is the selected region of the diffraction spot; The brightness B of the diffraction spot is obtained by integrating the brightness of each pixel within the selected region of the diffraction spot. mn The centroid O mn The position information P of the diffraction spot mn .

2. The method according to claim 1, characterized in that, The centroid O of the region to be selected is determined by using the major axis of the region to be selected as the diameter D. mn With the centroid O mn Centered on a circle, the circular region defined by the diameter D is the selected region of the diffraction spot, including: Using the major axis of the first region to be selected as the first diameter D1, determine the first centroid O of the first region to be selected. mn1 ; With the first centroid O mn1 Centered on the circle, the circular region defined by the first diameter D1 is the second region to be selected; Using the major axis of the second region to be selected as the second diameter D2, determine the second centroid O of the second region to be selected. mn2 ; Repeat the above process until the second centroid O is reached. mn2 With the first mass O mn1 The spacing is less than a preset spacing threshold, with the second centroid O mn2 The circular region centered on the second diameter D2 is the selected region of the diffraction spot.

3. The method according to any one of claims 1-2, characterized in that, include: The diffraction test results include: zero-order light intensity R0; the zero-order light intensity R0 is calculated according to the following formula: Among them, B 00 B is the brightness of the diffraction spot at the center. mn The brightness of each of the diffraction spots is denoted as R0; the zero-order intensity R0 is used to represent the ratio of the brightness of the central diffraction spot to the sum of the brightness of all diffraction spots.

4. The method according to any one of claims 1-2, characterized in that, include: The diffraction test results include: spot uniformity U; the spot uniformity U is calculated according to the following formula: Among them, B max B represents the maximum spot brightness among all the diffraction spots. min The minimum spot brightness among all the diffraction spots.

5. The method according to any one of claims 1-2, characterized in that, include: The diffraction test results include: diffraction efficiency DE; the diffraction efficiency DE is calculated according to the following formula: Among them, B 00 B is the brightness of the diffraction spot at the center. mn P represents the brightness of each of the diffraction spots. C P is the optical power of the central beam. i The laser power is [value missing].

6. A testing device for diffractive optical elements, characterized in that, include: The first test information module is used to acquire the diffraction beam pattern formed by the diffraction beam emitted by the diffraction optical element entering the transmission screen when the light source and the diffraction optical element are in the first position, and obtain the first test information. The diffraction beam pattern includes a plurality of diffraction spots; the first test information includes: spot position information P of each of the diffraction spots. mn and spot brightness B mn ; The second test information module is used to obtain second test information of the diffracted beam emitted by the diffracted optical element when the light source and the diffracting optical element are in the second position; the second test information includes: the central beam optical power P. C The central beam power P C The optical power of the central beam in the diffraction beam emitted by the diffraction optical element; The third test information module is used to obtain third test information of the laser emitted by the light source when the light source and the diffractive optical element are in the second position; the third test information includes: laser power P. i The laser power P i The light power of the laser emitted by the light source; The diffraction test result determination module is used to determine the diffraction test result of the diffraction optical element based on the first test information, the second test information, and the third test information. The first test information module is further configured to determine the peak position P of each of the diffraction spots. mn_max and peak brightness B mn_max According to the peak brightness B of the diffraction spot mn_max The selected region of the diffraction spot is determined by a preset selected ratio threshold δ; the spot brightness within the selected region is greater than δ. B mn_max Using the major axis of the region to be selected as the diameter D, determine the centroid O of the region to be selected. mn With the centroid O mn Centered on a circle, a circular region defined by the diameter D is selected as the region of the diffraction spot; the spot brightness B is calculated by integrating the brightness of the diffraction spot based on the selected region. mn The centroid O mn The position information P of the diffraction spot mn .

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program adapted to be loaded and executed by a processor to cause a computer device having the processor to perform the method of any one of claims 1-5.

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