Solar simulator detection method and system

Abstract

The invention discloses a solar simulator detection method and system, relates to the field of optical systems, and is used for solving the problem of detecting optical indexes of a solar simulator. The method comprises the following steps: enabling an image plane to be positioned on a light emitting side of the solar simulator, receiving emergent light and imaging to obtain a first light field distribution image; for any pixel of the first light field distribution image, the irradiance value of the light received at the position corresponding to the pixel on the image plane is obtained according to a preset relation and the gray value of the pixel, and the preset relation describes the relation between the gray value of each pixel of the image obtained by the image plane and the irradiance value of the light received at the position corresponding to each pixel on the image plane; and obtaining an optical index of emergent light of the solar simulator according to the irradiance value corresponding to each pixel of the first light field distribution image. The emergent light of the solar simulator is imaged, the irradiance condition of the emergent light of the solar simulator is obtained according to the gray value of each pixel of the image, and then the optical index of the emergent light of the solar simulator is obtained.

Description

Technical Field

[0001] The present invention relates to the field of optical systems, and in particular to a solar simulator detection method and system. Background Art

[0002] A solar simulator is an artificial light source device that can simulate the irradiance characteristics of sunlight, such as spectrum, light intensity, irradiance uniformity, and collimation. It is mainly used in laboratory environments to replace real sunlight for scientific research or product testing. Its core purpose is to reproduce the key parameters of sunlight under controllable conditions to meet the experimental needs of aerospace, photovoltaics, material aging, agriculture and other fields. For example: solar cell research and development and testing, performance evaluation of photovoltaic modules and systems, materials science research, environmental and climate simulation, calibration of optical devices and systems, aerospace, and sustainable development and energy transformation. Solar simulators not only provide key tools for scientific research and technological development, but also promote the advancement and application of solar energy technology, making important contributions to global energy transformation and environmental protection.

[0003] The optical indicators of a solar simulator are key factors in ensuring the accuracy, reliability, and repeatability of experimental results. Optical indicators such as irradiation intensity and irradiation non-uniformity. Detecting and controlling irradiation intensity ensures that experimental conditions are consistent with the real environment, while detecting and controlling irradiation non-uniformity ensures that test samples are evaluated under a uniform light intensity distribution. The necessity of these indicators is reflected in many fields such as solar cell testing, material research, and optical device calibration, and is of great significance to scientific research and industrial applications. By precisely controlling the optical indicators of a solar simulator, the quality of experimental data can be improved and the development and application of related technologies can be promoted. Summary of the Invention

[0004] The purpose of the present invention is to provide a solar simulator detection method and system, which can realize the detection of optical indicators of the solar simulator.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A solar simulator detection method, comprising:

[0007] The image plane is located on the light-emitting side of the solar simulator, receives the emitted light of the solar simulator and performs imaging, and obtains a first light field distribution image on the image plane;

[0008] For any pixel of the first light field distribution image, obtain an irradiance value of light received at a position corresponding to the pixel on the image plane according to a preset relationship and a grayscale value of the pixel, wherein the preset relationship describes a relationship between the grayscale value of each pixel in the image obtained on the image plane and the irradiance value of light received at a position corresponding to each pixel on the image plane;

[0009] The optical index of the outgoing light of the solar simulator is obtained according to the irradiance value corresponding to each pixel of the first light field distribution image.

[0010] In some implementations, obtaining the preset relationship includes:

[0011] Allowing light emitted from a preset light source to illuminate a test surface, and measuring irradiance values ​​at multiple positions on the test surface;

[0012] Positioning the image plane on the test surface, receiving the emitted light from the preset light source and performing imaging, and obtaining a second light field distribution image on the image plane;

[0013] The preset relationship is obtained according to the irradiance values ​​of the multiple positions and the grayscale values ​​of the pixels corresponding to the multiple positions in the second light field distribution image.

[0014] In some embodiments, the optical indicators of the output light of the solar simulator include irradiance distribution;

[0015] Acquiring a first light field distribution image on the image plane includes: acquiring multiple frames of the first light field distribution image;

[0016] The optical indicators of the output light of the solar simulator are obtained as follows:

[0017] For any pixel of the first light field distribution image, the average value of the irradiance values ​​corresponding to this pixel in the multiple frames of the first light field distribution image is obtained as the detected irradiance value of this pixel, and further based on the detected irradiance values ​​of each pixel of the first light field distribution image, the irradiance distribution of the output light of the solar simulator is obtained.

[0018] In some embodiments, the optical index of the output light of the solar simulator includes irradiance non-uniformity;

[0019] The optical indicators of the output light of the solar simulator are obtained as follows:

[0020] Obtaining a maximum irradiance value and a minimum irradiance value based on the irradiance values ​​corresponding to the pixels of the first light field distribution image, obtaining a first ratio of a difference between the maximum irradiance value and the minimum irradiance value and a sum of the maximum irradiance value and the minimum irradiance value, and using the first ratio to characterize the irradiance non-uniformity of the emergent light of the solar simulator;

[0021] Alternatively, the average value of the irradiance values ​​corresponding to each pixel of the first light field distribution image is obtained to obtain the average irradiance value. For any pixel of the first light field distribution image, the difference between the irradiance value corresponding to the pixel and the average irradiance value is obtained, and a second ratio to the average irradiance value is obtained. The second ratio of each pixel of the first light field distribution image is used to characterize the irradiance unevenness of the output light of the solar simulator.

[0022] In some embodiments, the optical index of the output light of the solar simulator includes irradiance instability;

[0023] Acquiring a first light field distribution image on the image plane includes: acquiring a plurality of frames of the first light field distribution image within a first preset time length;

[0024] The optical indicators of the output light of the solar simulator are obtained as follows:

[0025] For any pixel of the first light field distribution image, the average value and standard deviation of the irradiance value corresponding to this pixel in the multiple frames of the first light field distribution image are obtained, and a fourth ratio of the standard deviation to the average value is obtained. The fourth ratio is used to characterize the irradiance instability of the output light of the solar simulator within the first preset time length.

[0026] A solar simulator detection system, comprising:

[0027] An imaging device, configured to receive the emitted light from the solar simulator and perform imaging to obtain a first light field distribution image;

[0028] A processing device is communicatively connected to the imaging device and is used to obtain, for any pixel of the first light field distribution image, an irradiance value of light received at a position corresponding to the pixel on the image plane of the imaging device according to a preset relationship and the grayscale value of the pixel. The preset relationship describes the relationship between the grayscale value of each pixel of the image obtained by the imaging device and the irradiance value of light received at a position corresponding to each pixel on the image plane of the imaging device, and obtains the optical indicators of the output light of the solar simulator according to the irradiance values ​​corresponding to each pixel of the first light field distribution image.

[0029] In some embodiments, the field of view angle of the imaging device satisfies the following conditional formula: object ≥D,h object =2*L*tan(θ / 2);

[0030] Wherein, D represents the diameter of the light opening of the solar simulator, θ represents the field of view angle of the imaging device, and L represents the distance from the imaging device to the solar simulator.

[0031] In some embodiments, the magnification of the imaging device satisfies the following condition: β = h image / h object , h object =2*L*tan(θ / 2); where β represents the magnification of the imaging device, h image represents the smaller value between the length and width of the image plane of the imaging device, θ represents the field of view of the imaging device, and L represents the distance from the imaging device to the solar simulator.

[0032] In some embodiments, further comprising:

[0033] a cooling device, configured to dissipate heat from the imaging device;

[0034] A monitoring module is used to obtain the temperature of the imaging device, and is also used to control the cooling device to start when the temperature of the imaging device is greater than or equal to a first temperature value, and when the temperature of the imaging device is in the interval of [first temperature value, second temperature value], control the operating parameter value of the cooling device to change according to a preset linear relationship with the temperature of the imaging device, and the operating parameter value of the cooling device is in the interval of [first parameter value, second parameter value], and when the temperature of the imaging device is less than or equal to a third temperature value, control the cooling device to shut down, wherein the heat dissipation of the cooling device per unit time is related to the operating parameter value of the cooling device, the second temperature value is greater than the first temperature value, the third temperature value is less than the first temperature value, and the second parameter value is greater than the first parameter value.

[0035] In some embodiments, further comprising:

[0036] Bracket;

[0037] A pan-tilt platform is arranged on the bracket, the imaging device is arranged on the pan-tilt platform, and the pan-tilt platform is used to adjust the optical axis direction of the imaging device.

[0038] It can be seen from the above technical solution that the solar simulator detection method and system provided by the present invention include: placing the image plane on the light-emitting side of the solar simulator, receiving the emitted light of the solar simulator and performing imaging, and obtaining a first light field distribution image on the image plane; for any pixel of the first light field distribution image, obtaining the irradiance value of the light received at the corresponding position of the pixel on the image plane according to a preset relationship and the grayscale value of the pixel, and the preset relationship describes the relationship between the grayscale value of each pixel of the image obtained on the image plane and the irradiance value of the light received at the position corresponding to each pixel on the image plane; according to the irradiance value corresponding to each pixel of the first light field distribution image, the optical indicators of the emitted light of the solar simulator are obtained.

[0039] The beneficial effect of the present invention is that by imaging the output light of the solar simulator, the irradiance of the output light of the solar simulator is obtained according to the grayscale value of each pixel of the image, and then the optical index of the output light of the solar simulator is obtained, thereby realizing the detection of the optical index of the solar simulator. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0041] Figure 1 A flow chart of a solar simulator detection method provided by an embodiment;

[0042] Figure 2 A schematic diagram of a solar simulator detection system provided by an embodiment;

[0043] Figure 3 A response curve diagram of a sensor of an imaging device of a solar simulator detection system according to an embodiment;

[0044] Figure 4 The relationship between the operating parameter value of the cooling device of the solar simulator and the temperature of the imaging device in one embodiment;

[0045] Figure 5 A schematic diagram of a visual interface of a solar simulator detection system provided by an embodiment;

[0046] Figure 6 A schematic diagram of the architecture of a solar simulator detection system provided by an embodiment.

[0047] The reference numerals in the drawings of the specification include:

[0048] 100 - solar simulator, 101 - imaging device, 102 - filter element, 103 - monitoring module, 104 - cooling device, 105 - image acquisition card, 106 - processing device, 107 - visualization interface, 108 - storage device. DETAILED DESCRIPTION

[0049] In order to make the person skilled in the art better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by the person skilled in the art without creative work should belong to the protection scope of the present application.

[0050] Reference can be made to Figure 1 , Figure 1 A flow chart of a solar simulator detection method provided by an embodiment is shown in the figure. The solar simulator detection method comprises the following steps:

[0051] S11: The image plane is located on the light exit side of the solar simulator, the exit light of the solar simulator is received and imaged, and a first light field distribution image is obtained on the image plane.

[0052] On the light exit side of the solar simulator, the exit light of the solar simulator is received and imaged, and the obtained first light field distribution image is an image formed by the exit light of the solar simulator. The gray value of the first light field distribution image is related to the irradiance of the light received by the image plane, and the first light field distribution image can reflect the light field distribution of the exit light of the solar simulator, i.e. the irradiance distribution of the exit light of the solar simulator.

[0053] S12: For any pixel of the first light field distribution image, the irradiance value of the light received by the corresponding position of the pixel on the image plane is obtained according to a preset relationship and the gray value of the pixel, and the preset relationship describes the relationship between the gray value of each pixel of the image obtained by the image plane and the irradiance value of the light received by the corresponding position of the pixel on the image plane.

[0054] The gray value of any pixel of the first light field distribution image is related to the irradiance of the light received by the corresponding position of the pixel on the image plane. The preset relationship can be calibrated in advance, i.e. the relationship between the gray value of each pixel of the image obtained by the image plane and the irradiance value of the light received by the corresponding position of the pixel on the image plane.

[0055] S13: The optical index of the exit light of the solar simulator is obtained according to the irradiance values corresponding to each pixel of the first light field distribution image.

[0056] The optical index of the exit light of the solar simulator refers to the data reflecting the optical performance of the exit light of the solar simulator.

[0057] The solar simulator detection method of this embodiment images the outgoing light of the solar simulator, obtains the irradiance of the outgoing light of the solar simulator based on the grayscale value of each pixel of the image, and then obtains the optical indicators of the outgoing light of the solar simulator, thereby realizing the detection of the optical indicators of the solar simulator.

[0058] In some embodiments, obtaining the preset relationship includes the following steps:

[0059] S21: irradiating a test surface with light emitted from a preset light source, and measuring irradiance values ​​at multiple positions on the test surface.

[0060] S22: placing the image plane on the test plane, receiving the emitted light from the preset light source and performing imaging, and obtaining a second light field distribution image on the image plane.

[0061] S23: Obtaining the preset relationship according to the irradiance values ​​of the multiple positions and the grayscale values ​​of the pixels corresponding to the multiple positions in the second light field distribution image.

[0062] Light emitted from a predetermined light source is directed onto a test surface. Multiple locations are selected on the test surface, and the irradiance is measured at each location to obtain an irradiance value at each location. For each of the multiple locations selected on the test surface, a pixel corresponding to the location is determined in the second light field distribution image, and a grayscale value of the pixel corresponding to the location is obtained. Furthermore, a predetermined relationship is obtained based on the irradiance values ​​corresponding to the multiple locations on the test surface and the grayscale values ​​of the pixels corresponding to the multiple locations in the second light field distribution image.

[0063] Irradiance, also known as irradiance intensity, refers to the radiant power received per unit area. It is used to describe the energy distribution of light or other electromagnetic radiation. Its SI unit is watts per square meter (W / m²). In some embodiments, a radiometer can be used to measure irradiance at any location. A standard radiometer can be used. The preset light source can use a light source with a uniform irradiance distribution of the emitted light, which can be referred to as a standard uniform light source.

[0064] In some embodiments, the optical indicators of the output light of the solar simulator include irradiance distribution. Obtaining the first light field distribution image on the image plane includes: obtaining multiple frames of the first light field distribution image. Obtaining the optical indicators of the output light of the solar simulator includes: for any pixel of the first light field distribution image, obtaining the average value of the irradiance values ​​corresponding to the pixel in the multiple frames of the first light field distribution image as the detected irradiance value of the pixel, and further obtaining the irradiance distribution of the output light of the solar simulator based on the detected irradiance values ​​of each pixel of the first light field distribution image.

[0065] For any pixel in the obtained multiple frames of the first light field distribution image, the irradiance values ​​corresponding to that pixel in the multiple frames of the first light field distribution image are averaged, and the obtained average value is used as the detected irradiance value of that pixel. Furthermore, by obtaining the detected irradiance values ​​for each pixel, the irradiance distribution of the output light from the solar simulator can be obtained. Multiple frames of the first light field distribution image can be obtained for the output light from the solar simulator through the image plane within a preset time period.

[0066] For example, the average irradiance value for pixel (x, y) may be calculated according to the following formula:

[0067] ;

[0068] in, Indicates the average value of the irradiance value corresponding to the pixel (x, y), E t (x, y) represents the irradiance value corresponding to the pixel (x, y) of the t-th frame of the first light field distribution image, and n represents the number of n frames of the first light field distribution image.

[0069] In some embodiments, the optical index of the output light of the solar simulator includes irradiance unevenness. Obtaining the optical index of the output light of the solar simulator includes: obtaining a maximum irradiance value and a minimum irradiance value according to the irradiance values ​​corresponding to each pixel of the first light field distribution image, obtaining a first ratio of the difference between the maximum irradiance value and the minimum irradiance value, and the sum of the maximum irradiance value and the minimum irradiance value, and characterizing the irradiance unevenness of the output light of the solar simulator with the first ratio. According to the irradiance values ​​corresponding to each pixel of the first light field distribution image, find the maximum irradiance value and the minimum irradiance value therein, and obtain a first ratio, the first ratio being the ratio of the difference between the maximum irradiance value and the minimum irradiance value and the sum of the maximum irradiance value and the minimum irradiance value, and characterizing the irradiance unevenness of the output light of the solar simulator with the first ratio.

[0070] In some embodiments, obtaining a first light field distribution image on the image plane includes: obtaining multiple frames of the first light field distribution image. Obtaining the optical index of the output light of the solar simulator includes: for any pixel of the first light field distribution image, obtaining the average value of the irradiance values ​​corresponding to the pixel in the multiple frames of the first light field distribution image as the detected irradiance value of the pixel; obtaining the maximum irradiance value and the minimum irradiance value based on the detected irradiance values ​​of each pixel, obtaining the difference between the maximum irradiance value and the minimum irradiance value, and obtaining a third ratio of the sum of the maximum irradiance value and the minimum irradiance value, and using the third ratio to characterize the irradiance unevenness of the output light of the solar simulator. For any pixel in the multiple frames of the first light field distribution image obtained, average the irradiance values ​​corresponding to the pixel in the multiple frames of the first light field distribution image, and use the obtained average value as the detected irradiance value of the pixel. According to the detected irradiance values ​​of each pixel, a maximum irradiance value and a minimum irradiance value are obtained, and a third ratio is obtained. The third ratio is used to characterize the irradiance non-uniformity of the emergent light of the solar simulator.

[0071] For example, it can be calculated according to the following formula:

[0072] ;

[0073] Where H represents the irradiation non-uniformity, Indicates the maximum irradiance value among the detected irradiance values ​​of each pixel. Indicates the minimum irradiance value among the detected irradiance values ​​of each pixel.

[0074] In some embodiments, obtaining the optical index of the output light of the solar simulator includes: obtaining the average value of the irradiance values ​​corresponding to each pixel of the first light field distribution image to obtain the average irradiance value; for any pixel of the first light field distribution image, obtaining the difference between the irradiance value corresponding to the pixel and the average irradiance value; and obtaining a second ratio of the irradiance value to the average irradiance value; the second ratio of each pixel of the first light field distribution image is used to characterize the irradiance unevenness of the output light of the solar simulator. For example, it can be calculated according to the following formula: H(x,y)=(E(x,y)–E avg ) / E avg ×100%, where H(x,y) represents the irradiance unevenness of the pixel (x,y) on the image plane, E(x,y) represents the irradiance value corresponding to the pixel (x,y), and E avg Indicates the average irradiance value. For example, the non-uniformity value can be mapped to a color gradient to display the irradiance non-uniformity, such as: blue represents below the average value, green represents close to the average value, and red represents above the average value.

[0075] Irradiance nonuniformity describes the differences in the distribution of light intensity across a test surface and is a key performance indicator for solar simulators, optical systems, or lighting equipment. Excessive irradiance nonuniformity can distort experimental or test results, such as errors in photovoltaic cell efficiency measurements or uneven material aging tests.

[0076] In some embodiments, the optical indicators of the output light of the solar simulator include irradiation instability; obtaining the first light field distribution image on the image plane includes: obtaining multiple frames of the first light field distribution image within a first preset time length; obtaining the optical indicators of the output light of the solar simulator includes: for any pixel of the first light field distribution image, obtaining the average value and standard deviation of the irradiance values ​​corresponding to this pixel of the multiple frames of the first light field distribution image, obtaining a fourth ratio of the standard deviation to the average value, and using the fourth ratio to characterize the irradiation instability of the output light of the solar simulator within the first preset time length.

[0077] For example, it can be calculated according to the following formula:

[0078] ;

[0079] Among them, J(x,y) represents the irradiance instability of the position of the pixel (x,y) on the image plane. represents the average value of the irradiance values ​​corresponding to the pixels (x, y) of the multiple frames of the first light field distribution image obtained within the first preset time length, The standard deviation of the irradiance values ​​corresponding to the pixels (x, y) of the multiple frames of the first light field distribution image obtained within the first preset time period.

[0080] This embodiment also provides a solar simulator detection system, including:

[0081] An imaging device, configured to receive the emitted light from the solar simulator and perform imaging to obtain a first light field distribution image;

[0082] A processing device is communicatively connected to the imaging device and is used to obtain, for any pixel of the first light field distribution image, an irradiance value of light received at a position corresponding to the pixel on the image plane of the imaging device according to a preset relationship and the grayscale value of the pixel. The preset relationship describes the relationship between the grayscale value of each pixel of the image obtained by the imaging device and the irradiance value of light received at a position corresponding to each pixel on the image plane of the imaging device, and obtains the optical indicators of the output light of the solar simulator according to the irradiance values ​​corresponding to each pixel of the first light field distribution image.

[0083] The solar simulator detection system of this embodiment images the emitted light of the solar simulator, obtains the irradiance of the emitted light of the solar simulator according to the grayscale value of each pixel of the image, and then obtains the optical index of the emitted light of the solar simulator, thereby realizing the detection of the optical index of the solar simulator. Figure 2 , Figure 2 This is a schematic diagram of a solar simulator detection system provided by an embodiment. The imaging device 101 is disposed on the light-emitting side of the solar simulator 100 , and the processing device 106 is communicatively connected to the imaging device 101 .

[0084] In some embodiments, the field of view angle of the imaging device 101 satisfies the following condition: object ≥D,h object =2*L*tan(θ / 2); where D represents the diameter of the light port of the solar simulator, θ represents the field of view of the imaging device, and L represents the distance from the imaging device to the solar simulator. The light port of the solar simulator 100 is the light outlet of the solar simulator 100, and light is output from the light port of the solar simulator 100. The field of view of the imaging device 101 satisfies the above conditions so that the light emitted by the solar simulator 100 is completely within the field of view of the imaging device 101. In some embodiments, it can be h object >D, so as to avoid cutting the edge of the spot of the light emitted by the solar simulator 100 when the edge of the image needs to be cut due to distortion or installation error of the lens of the imaging device 101. This can provide a buffer area for later image correction (such as dedistortion and flat field compensation) and ensure that the uniform center area of ​​the spot of the light emitted by the solar simulator 100 is completely within the effective range of the sensor of the imaging device 101. In some embodiments, h object ≥D (1 + 10%), so that h object At least 10% margin should be reserved compared to D.

[0085] In some embodiments, the magnification of the imaging device 101 satisfies the following condition: β = h image / h object , h object =2*L*tan(θ / 2); where h image represents the smaller value between the length and width of the image plane of the imaging device, θ represents the field of view of the imaging device, and L represents the distance from the imaging device to the solar simulator.

[0086] In some embodiments, the pixel size of the image plane of the imaging device 101 satisfies the following condition: a≤(β×s) / N, where a represents the pixel size of the image plane of the imaging device, β represents the magnification of the imaging device, s represents the size of the area to be detected in the exit spot of the solar simulator, and N is a positive integer greater than or equal to 20.

[0087] Exemplarily, the main technical indicators of a solar simulator are shown in Table 1 as follows:

[0088] Table 1

[0089]

[0090] The diameter of the light passage of the solar simulator is 120 mm, and considering a 10% margin, the imaging device is required to have h object = 132 mm. Assuming that the sensor of the imaging device selects a 1-inch sensor with a size of 14.1 mm x 8.5 mm, then: β = h image / h object = 8.5 / 132 ≈ 0.064. Assuming that the details of a 2 mm area in the exit light spot of the solar simulator are required to be resolved, then: β x 2 mm = 0.064 x 2 mm = 0.128 mm = 128 μm, that is, the 2 mm area in the exit light spot of the solar simulator corresponds to a 128 μm area in the sensor of the imaging device. Assuming that the pixel size of the sensor is 3.45 μm x 3.45 μm, then each 2 mm light spot is covered by about 37 pixels, which can meet the general uniformity detection requirements.

[0091] In summary, the imaging device can select a face array black and white camera, a global shutter, support automatic exposure, manual exposure and one-key exposure mode, can capture the instantaneous changes of the light spot at high speed, avoid the distortion of the rolling shutter, the pixel size is 3.45 μm x 3.45 μm, the resolution is 4096 x 2460, the data interface is compatible with Fast Ethernet (100 Mbit / s), and can refer to Figure 3 , Figure 3 FIG. 7 is a response curve diagram of the sensor of the imaging device of the solar simulator detection system according to an embodiment, in which the horizontal axis represents the wavelength in nm, and the vertical axis represents the quantum efficiency (QE), that is, the efficiency of converting incident photons into electrons at a specific wavelength, which can directly reflect the sensitivity of the sensor to light.

[0092] The lens of imaging device 101 directly impacts image quality, measurement accuracy, and system stability. Selection criteria are primarily based on the following: 1) To detect irradiance non-uniformity in the solar simulator 100, a low-distortion, high-resolution, and wide-spectrum transmittance lens is required. 2) To detect the light intensity distribution of the solar simulator 100, the high light intensity of the solar simulator 100 requires a wide dynamic range. Therefore, an aperture-adjustable lens with an F / 2.8 to F / 16 aperture is selected to improve depth of field and edge sharpness while avoiding overexposure. 3) The lens mount type should be a C-mount, a popular mount for industrial cameras. 4) The lens resolution (Modulation Transformer Function, MTF) should match the camera pixel size. 5) A multi-coated lens should be selected to reduce strong light reflections. 6) A metal barrel lens should be selected to avoid thermal drift during long-term operation. 7) The thin lens formula 1 / f = 1 / u + 1 / v should be used, where f represents the focal length of the lens, u represents the distance from the solar simulator to the lens (i.e., the object distance), and v represents the distance from the lens to the sensor (i.e., the image distance). If u = 400mm, and the magnification relationship is β = v / u, then v = β * u. If a complementary metal oxide semiconductor (CMOS) camera is used, and the camera parameters indicate β = 0.064, then v = 0.064 × 400 = 25.6mm, 1 / f = 1 / 400 + 1 / 25.6 = 0.0025 + 0.0390625 = 0.0415625, and f = 1 / 0.0415625 ≈ 24.06 mm. Based on the above, choose an industrial lens.

[0093] In some embodiments, a filter element 102 is provided on the light incident side of the imaging device 101. The filter element 102 is used to adjust the light intensity incident on the sensor of the imaging device 101 so that the light intensity received by the sensor is within the linear response range of the sensor to avoid saturation. The saturation light intensity is represented by I sat = (FWC×E photon ) / (QE×t EXP ×A), where I sat represents the saturation light intensity of the sensor, FWC represents the full well capacity, and E photon represents photon energy, QE represents quantum efficiency, t EXP represents the exposure time, and A represents the pixel area. For example, the full well capacity FWC = 51000e - , quantum efficiency QE=50%, pixel area A=3.45μm×3.45μm, photon energy E at a wavelength of 550nm photon About 3.61×10 -19 J, exposure time t EXP is 10ms, calculate I satAbout 3.1×105W / m 2 If the irradiance of the solar simulator 100 is 1353 W / m 2 , theoretically no filter element is needed. If the lens focusing increases the light intensity by 100 times, a filter element is required to attenuate the irradiated light intensity to about 50%. The filter element 102 can use a coated ND filter with uniform optical density. In summary, a neutral density filter can be selected. The material is a quartz glass substrate, the use band is 190nm ~ 2600nm, and the surface is coated with a durable metal film layer, which effectively avoids damage to the glass in a high temperature environment. The filter can evenly attenuate the light intensity in a wide spectral region and has a variety of transmittance options.

[0094] In some embodiments, the imaging device 101 may use a complementary metal oxide semiconductor (CMOS) camera, which is an imaging device based on a complementary metal oxide semiconductor (CMOS) sensor. Compared with traditional charge coupled device (CCD) cameras, CMOS cameras have the advantages of low power consumption, high integration, and low cost. With technological advancements, the imaging quality of CMOS cameras has approached or even surpassed that of CCD cameras.

[0095] In some embodiments, the solar simulator detection system further includes: an image acquisition card 105, which is communicatively connected to the imaging device 101. When selecting the image acquisition card 105, a comprehensive evaluation is required based on the camera interface, performance requirements, software compatibility, etc. The following key points can be considered when selecting the image acquisition card 105: 1) The camera data interface type is Gigabit Ethernet; 2) The camera resolution is 4096×2460, the maximum frame rate at full resolution can reach 11.6fps, the bit depth is Mono 8, and the redundancy factor is 1.2. Therefore, the following is true: single-frame data volume = (width×height×bit depth) / 8 = (4096×2460×8) / 8, original bandwidth (bps) = single-frame data volume × frame rate × 8, actual bandwidth requirement (Gbps) = original bandwidth × redundancy factor ≈ 1Gbps. 3) Software compatibility: MVS or third-party software supports the GigE Vision protocol. The Hikvision MV-GE1004 4-channel GigE capture card is a good choice. It features onboard cache, enabling on-card image processing and significantly reducing CPU load. It also supports lossless decompression of camera images, enabling lossless image transmission at higher frame rates.

[0096] In some embodiments, the imaging device 101 is provided with a heat sink to increase the surface area of ​​the imaging device 101 for natural heat dissipation. In some embodiments, a thermal pad is provided between the surface of the imaging device 101 and the heat sink to reduce the thermal resistance between the surface of the imaging device 101 and the heat sink. The thermal pad ensures a tight fit between the heat sink and the surface of the imaging device 101, significantly reducing interfacial thermal resistance. The thermal pad can be attached to the heat-generating area of ​​the imaging device 101 housing, with the heat sink pressed tightly against the pad to ensure there are no bubbles or gaps. Heat generated by sensors within the imaging device 101 is conducted through the housing to the thermal pad, and then to the heat sink, where it is further dissipated into the air through natural convection and thermal radiation. The thermal pad can be made of a thermally conductive silicone sheet, a substrate-free thermally conductive material containing a high-quality, low-modulus filler compound. It has excellent conformability, low hardness, and electrical insulation. The thermally conductive silicone sheet has a weak adhesive on both sides and a protective film on both sides, making it very easy to process and assemble while maintaining excellent thermal conductivity. The material has natural adhesive properties on both sides, allowing for excellent adhesion to adjacent component surfaces. For example, a 1mm thick, 203mm x 406mm thermally conductive silicone sheet can be used. Installing a heat sink can be considered a passive cooling method.

[0097] In some embodiments, the solar simulator detection system further includes a cooling device 104 for dissipating heat from the imaging device 101. The provision of the cooling device 104 can be considered as an active cooling method.

[0098] In some embodiments, the solar simulator detection system further comprises:

[0099] A cooling device 104, configured to dissipate heat from the imaging device 101;

[0100] The monitoring module 103 is configured to obtain the temperature of the imaging device 101 and to control the cooling device 104 to start when the temperature of the imaging device 101 is greater than or equal to a first temperature value, and to control the operating parameter value of the cooling device 104 to change according to a preset linear relationship with the temperature of the imaging device 101 when the temperature of the imaging device 101 is within the interval [first temperature value, second temperature value], and to control the cooling device 104 to shut down when the temperature of the imaging device 101 is less than or equal to a third temperature value, wherein the amount of heat dissipated by the cooling device 104 per unit time is related to the operating parameter value of the cooling device 104, the second temperature value is greater than the first temperature value, the third temperature value is less than the first temperature value, and the second parameter value is greater than the first parameter value. The monitoring module 103 monitors the temperature of the imaging device 101 and controls the cooling device 104 accordingly based on the temperature of the imaging device 101.

[0101] In some embodiments, the preset linear relationship indicates a linear relationship in which the operating parameter value of the cooling device 104 and the temperature of the imaging device 101 are positively correlated. That is, when the temperature of the imaging device 101 is within the interval [first temperature value, second temperature value], the higher the temperature of the imaging device 101, the larger the operating parameter value of the cooling device 104 is controlled to be. In some embodiments, the amount of heat dissipated by the cooling device 104 per unit time is positively correlated with the operating parameter value of the cooling device 104. That is, the larger the operating parameter value of the cooling device 104, the greater the amount of heat dissipated by the cooling device 104 per unit time.

[0102] In some embodiments, the monitoring module 103 is further configured to control the operating parameter value of the cooling device 104 to be the first parameter value when the temperature of the imaging device 101 is in the interval [third temperature value, first temperature value]. In some embodiments, the monitoring module 103 is further configured to control the operating parameter value of the cooling device 104 to be the second parameter value when the temperature of the imaging device 101 is in the interval [second temperature value, fourth temperature value], wherein the fourth temperature value is greater than the second temperature value. In some embodiments, the monitoring module 103 is further configured to control the imaging device 101 to stop operating when the temperature of the imaging device 101 is greater than the fourth temperature value. For example, reference may be made to Figure 4 , Figure 4 This figure shows the relationship between the operating parameter values ​​of the cooling device and the temperature of the imaging device of a solar simulator according to one embodiment. The horizontal axis represents the temperature of the imaging device 101 (in degrees Celsius), and the vertical axis represents the operating parameter values ​​of the cooling device 104. L represents the first temperature value, H represents the second temperature value, G represents the fourth temperature value, and (L-3) represents the third temperature value. The first operating parameter value of the cooling device 104 is 20%, and the second operating parameter value is 100%.

[0103] In this embodiment, the cooling device 104 is not limited to a fan and can be used, but is not limited to, a fan. Operating parameters for the fan include fan speed or air volume per unit time. The cooling device 104 can be located near the imaging device 101. For example, a small DC fan can be used. A low-vibration type should be selected to avoid affecting the imaging device 101, and the airflow should cover the main heat-generating areas of the imaging device 101, such as sensors. The fan can be the Noctua NF-A4×10 PWM, a quiet, reliable, and ultra-thin cooling fan. It measures 40mm×40mm×10mm, has an all-metal frame, is heat-resistant, has a 4-pin PWM interface that supports dynamic speed regulation, and has a DC12V power supply voltage with a current / power consumption of 0.05A / 0.6W. The magnetically stabilized SSO2 bearings offer low noise and long life, and come with four silicone shock-absorbing pads to reduce resonance noise.

[0104] In this embodiment, the temperature of the imaging device 101 is monitored and the cooling strategy is dynamically adjusted or the overheat protection mechanism is triggered based on the feedback temperature. In some embodiments, the temperature of the imaging device 101 can also be used as a data compensation reference to provide a temperature parameter for the image processing algorithm to correct signal noise or dark current drift caused by temperature changes.

[0105] In some embodiments, the solar simulator detection system further comprises: a support; a pan / tilt mounted on the support, the imaging device 101 mounted on the pan / tilt, and the pan / tilt for adjusting the optical axis of the imaging device 101. The support must comprehensively consider stability, compatibility, adjustment accuracy, and environmental adaptability. A tripod may be used, but is not limited to. When selecting a support, consider the following: 1) Stability and load-bearing capacity. The tripod's load-bearing capacity should be ≥ (camera weight + optical accessories weight + cooling mechanism weight, etc.) × 1.5. Material Selection: Carbon fiber is lightweight and vibration-resistant, suitable for high-precision laboratory environments, but is relatively expensive. Aluminum alloy is economical and durable, suitable for static or budget-constrained environments, but is heavier. Structural Design: Choose a tripod with a center column hook or a weighted attachment to enhance resistance to wind and ground vibration. 2) Height and Adjustment Range: The maximum height of the tripod should be close to the experimenter's comfortable operating height to avoid frequent bending. Tripods without a center column or with a removable center column are preferred to reduce shaking caused by extending the center column. 4) Environmental Adaptability. Corrosion Resistance: Choose a rust-resistant material. Temperature tolerance: Carbon fiber exhibits minimal deformation in extreme temperatures, making it suitable for wide temperature environments. 5) Compatibility and expandability: The tripod's top should include 1 / 4" to 3 / 8" screw holes to accommodate optical platform adapters or other instruments. If simultaneous multi-camera inspection is required, the tripod should support cross-arm or multi-panel assembly.

[0106] The optical axis of the imaging device 101 is adjusted using a gimbal to ensure strict alignment between the optical axis of the solar simulator 100 and the optical axis of the sensor of the imaging device 101. The gimbal can be, but is not limited to, a three-dimensional geared gimbal or a spherical gimbal. In some embodiments, the gimbal is compatible with quick-release plates, ensuring that it supports Arca-Swiss or Manfrotto quick-release systems for quick camera installation and removal. Aluminum alloy tripods and fluid gimbals are available.

[0107] In some embodiments, the solar simulator detection system also includes a visualization interface 107. As the core hub of human-computer interaction, the design of the visualization interface 107 needs to take into account functionality, ease of use, and scalability. According to application requirements, the main functions of the visualization interface 107 are: configuration of the parameters of the imaging device 101; real-time communication with the monitoring module 103, control of the working status of the cooling device 104 as needed, real-time display of temperature values, and the ability to set parameters such as the starting temperature and full-speed temperature of the cooling device 104; real-time visualization of optical parameters of the solar simulator, providing visualization tools such as irradiance distribution diagrams, irradiation non-uniformity thermal maps, and irradiation instability waveform diagrams; supporting automatic generation of detection reports, including measurement results, error analysis, and performance evaluation; possessing self-diagnosis capabilities, capable of detecting hardware failures and software anomalies, and providing fault prompts and solution suggestions. For example, you can refer to Figure 5 , Figure 5 This is a schematic diagram of a visual interface of a solar simulator detection system provided by an embodiment. In some implementations, the solar simulator detection system may further include a storage device 108 for storing data.

[0108] The processing method and process for the processing device 106 to obtain the optical indicators of the output light of the solar simulator 100 based on the first light field distribution image obtained by the imaging device 101 can all refer to the above-mentioned implementation method described in relation to the solar simulator detection method, and will not be repeated here. The software design of the solar simulator detection system of this embodiment plays a decisive role, and its functions mainly include the following aspects: 1) Camera drive and configuration: such as exposure time, gain, frame rate, resolution, etc. 2) Optical performance analysis: irradiance distribution is a spatial distribution calculated based on the grayscale value of the image; non-uniformity analysis is to calculate the standard deviation / mean of the image area; instability analysis is to calculate the irradiance change between frames. 3) Temperature control: temperature data is acquired and displayed in real time through the RS485 interface, and the starting temperature and full-speed temperature of the cooling device can be configured to achieve linear speed control of the cooling device. 4) Visual interface: real-time display of the original camera image and key parameters of the solar simulator, display of the irradiance distribution in the form of a heat map, color mapping to display the non-uniformity heat map, time series change curve to display the instability waveform, etc. 5) Test report generation: supports multiple formats of output, including data statistics such as irradiation intensity, irradiation non-uniformity, irradiation instability, etc., automatically adds time records and test conditions, etc. Figure 6 , Figure 6 This is a schematic diagram of the architecture of a solar simulator detection system provided in one embodiment. In summary, the imaging device-based solar simulator detection system of this embodiment can comprehensively evaluate the optical performance of the solar simulator through high-precision, high-resolution, and high-temporal-resolution detection methods to ensure that it meets the needs of scientific research and industrial applications.

[0109] For the image acquired by the imaging device 101, data preprocessing may be performed first, including dark current correction and flat field correction. The dark current correction may eliminate the dark current and noise of the imaging device 101, and the flat field correction may eliminate pixel response non-uniformity.

[0110] Dark current correction is expressed as:

[0111] ;

[0112] Among them, I dark (x, y) represents the dark current value of pixel (x, y), t represents the t-th frame image, and n represents the n-th frame image. dark (x, y) is obtained according to a dark field image, which is an image acquired by the imaging device 101 under no light conditions.

[0113] The flat field correction is expressed as:

[0114] ;

[0115] ;

[0116] ;

[0117] Among them, I flat (x, y) represents the flat field current value of pixel (x, y), t represents the t-th frame image, n represents the n-th frame image, mean() represents the mean function, I raw (x,y) represents the grayscale value of the pixel (x,y) in the original image, and I(x,y) represents the grayscale value of the pixel (x,y) in the corrected image. flat (x, y) is obtained according to a flat-field image. The flat-field image is an image obtained by the imaging device 101 of a uniform light source. The uniform light source is a light source with a uniform irradiance distribution of the emitted light.

[0118] E(x,y) = k * I(x,y), where E(x,y) represents the irradiance value corresponding to the pixel (x,y) and k represents the coefficient.

[0119] The solar simulator can be a collimated light that produces a spectrum close to AM1.5G. The solar simulator detection method and system of this embodiment can quantify the unevenness of the light spot by imaging the output light of the solar simulator and analyzing the spatial distribution of the image; by continuously imaging the output light of the solar simulator and calculating the fluctuation of the irradiance through time series images. In view of the high irradiance characteristics of the solar simulator, the dynamic range and high frame rate acquisition capability of the imaging device are optimized to solve the problem of easy saturation or slow response of traditional sensors. In view of the influence of dark current, noise and other factors of the imaging device, a real-time calibration algorithm is designed, and a temperature monitoring module is integrated to improve the long-term stability of the detection system.

[0120] The solar simulator detection method and system of this embodiment images the solar simulator's emitted light and calculates its unevenness and instability through spatial-temporal analysis. Compared to traditional detection technologies, this method and system offers greater integration, faster detection speeds, lower costs, and improved spatial resolution. In particular, the core image processing technology and algorithms significantly reduce system complexity and costs while ensuring detection accuracy, leading to more standardized detection processes in specific areas such as photovoltaic module testing and spacecraft thermal vacuum testing.

[0121] The above is a detailed introduction to the solar simulator detection method and system provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only intended to help understand the method and core ideas of the present invention. It should be pointed out that, for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the scope of protection of the present invention.

Claims

1. A solar simulator detection method, characterized in that: include: The image plane is located on the light-emitting side of the solar simulator, receives the emitted light of the solar simulator and performs imaging, and obtains a first light field distribution image on the image plane; For any pixel of the first light field distribution image, obtain an irradiance value of light received at a position corresponding to the pixel on the image plane according to a preset relationship and a grayscale value of the pixel, wherein the preset relationship describes a relationship between the grayscale value of each pixel in the image obtained on the image plane and the irradiance value of light received at a position corresponding to each pixel on the image plane; The optical index of the emergent light of the solar simulator is obtained according to the irradiance value corresponding to each pixel of the first light field distribution image.

2. The solar simulator detection method according to claim 1, characterized in that: Obtaining the preset relationship includes: Allowing light emitted from a preset light source to illuminate a test surface, and measuring irradiance values ​​at multiple positions on the test surface; Positioning the image plane on the test surface, receiving the emitted light from the preset light source and performing imaging, and obtaining a second light field distribution image on the image plane; The preset relationship is obtained according to the irradiance values ​​of the multiple positions and the grayscale values ​​of the pixels corresponding to the multiple positions in the second light field distribution image.

3. The solar simulator detection method according to claim 1, characterized in that: The optical indicators of the output light of the solar simulator include irradiance distribution; Acquiring a first light field distribution image on the image plane includes: acquiring multiple frames of the first light field distribution image; The optical indicators of the output light of the solar simulator are obtained as follows: For any pixel of the first light field distribution image, the average value of the irradiance values ​​corresponding to this pixel in the multiple frames of the first light field distribution image is obtained as the detected irradiance value of this pixel, and further based on the detected irradiance values ​​of each pixel of the first light field distribution image, the irradiance distribution of the output light of the solar simulator is obtained.

4. The solar simulator detection method according to claim 1, characterized in that: The optical indicators of the output light of the solar simulator include irradiance unevenness; The optical indicators of the output light of the solar simulator are obtained as follows: Obtaining a maximum irradiance value and a minimum irradiance value based on the irradiance values ​​corresponding to the pixels of the first light field distribution image, obtaining a first ratio of a difference between the maximum irradiance value and the minimum irradiance value and a sum of the maximum irradiance value and the minimum irradiance value, and using the first ratio to characterize the irradiance non-uniformity of the emergent light of the solar simulator; Alternatively, the average value of the irradiance values ​​corresponding to each pixel of the first light field distribution image is obtained to obtain the average irradiance value. For any pixel of the first light field distribution image, the difference between the irradiance value corresponding to the pixel and the average irradiance value is obtained, and a second ratio to the average irradiance value is obtained. The second ratio of each pixel of the first light field distribution image is used to characterize the irradiance unevenness of the output light of the solar simulator.

5. The solar simulator detection method according to claim 1, characterized in that: The optical indicators of the output light of the solar simulator include irradiance instability; Acquiring a first light field distribution image on the image plane includes: acquiring a plurality of frames of the first light field distribution image within a first preset time length; The optical indicators of the output light of the solar simulator are obtained as follows: For any pixel of the first light field distribution image, the average value and standard deviation of the irradiance value corresponding to this pixel in the multiple frames of the first light field distribution image are obtained, and a fourth ratio of the standard deviation to the average value is obtained. The fourth ratio is used to characterize the irradiance instability of the output light of the solar simulator within the first preset time length.

6. A solar simulator detection system, characterized in that: include: An imaging device, configured to receive the emitted light from the solar simulator and perform imaging to obtain a first light field distribution image; A processing device is communicatively connected to the imaging device and is used to obtain, for any pixel of the first light field distribution image, an irradiance value of light received at a position corresponding to the pixel on the image plane of the imaging device according to a preset relationship and the grayscale value of the pixel. The preset relationship describes the relationship between the grayscale value of each pixel of the image obtained by the imaging device and the irradiance value of light received at a position corresponding to each pixel on the image plane of the imaging device, and obtains the optical indicators of the output light of the solar simulator according to the irradiance values ​​corresponding to each pixel of the first light field distribution image.

7. The solar simulator detection system according to claim 6, characterized in that: The field of view angle of the imaging device satisfies the following conditional formula: object ≥D,h object =2*L*tan(θ / 2); wherein D represents the diameter of the light opening of the solar simulator, θ represents the field of view angle of the imaging device, and L represents the distance from the imaging device to the solar simulator.

8. The solar simulator detection system according to claim 6, characterized in that: The magnification of the imaging device satisfies the following condition: β = h image / h object , h object =2*L*tan(θ / 2); where β represents the magnification of the imaging device, h image represents the smaller value between the length and width of the image plane of the imaging device, θ represents the field of view of the imaging device, and L represents the distance from the imaging device to the solar simulator.

9. The solar simulator detection system according to claim 6, characterized in that: Also includes: a cooling device, configured to dissipate heat from the imaging device; A monitoring module is used to obtain the temperature of the imaging device, and is also used to control the cooling device to start when the temperature of the imaging device is greater than or equal to a first temperature value, and when the temperature of the imaging device is in the interval of [first temperature value, second temperature value], control the operating parameter value of the cooling device to change according to a preset linear relationship with the temperature of the imaging device, and the operating parameter value of the cooling device is in the interval of [first parameter value, second parameter value], and when the temperature of the imaging device is less than or equal to a third temperature value, control the cooling device to shut down, wherein the heat dissipation of the cooling device per unit time is related to the operating parameter value of the cooling device, the second temperature value is greater than the first temperature value, the third temperature value is less than the first temperature value, and the second parameter value is greater than the first parameter value.

10. The solar simulator detection system according to any one of claims 6 to 9, characterized in that: Also includes: Bracket; A pan-tilt platform is arranged on the bracket, the imaging device is arranged on the pan-tilt platform, and the pan-tilt platform is used to adjust the optical axis direction of the imaging device.

Images