Method of searching for exposure time and quantum efficiency measurement system

Abstract

The application provides a method for searching exposure time and a quantum efficiency measuring system, comprising: a data processing module configured to configure fixed parameters of an image acquisition module and wavelengths of a wavelength configuration device; the image acquisition module is controlled to determine a candidate exposure time set according to a search step and an initial value of exposure time; after the wavelengths of the wavelength configuration device are configured, single-band light configured by the wavelength configuration device is received through an optical fiber bundle; a target exposure time is selected from the candidate exposure time set multiple times; images are captured multiple times under the environment of the wavelength of the wavelength configuration device; if the images do not occur light cutoff and satisfy a preset image saturation constraint condition and an image linearity constraint condition, the target exposure time is taken as a set of exposure times corresponding to the current wavelength; and a set of exposure times corresponding to the wavelength of each wavelength configuration device is searched until a set of exposure times corresponding to the wavelength of each wavelength configuration device is searched. The method is used to accurately search for exposure time meeting the linearity requirement.

Description

Technical Field

[0001] This invention relates to the field of image sensor testing technology, and in particular to a method for searching exposure time and a quantum efficiency measurement system. Background Technology

[0002] Quantum efficiency (QE) is a parameter describing a pixel's ability to convert photons into electrons, and it's a crucial parameter for evaluating the performance of an image sensor. A higher quantum efficiency indicates a stronger photoelectric conversion capability at a given wavelength, resulting in better low-light performance. As an evaluation parameter for image sensors, quantum efficiency measures the ability of a pixel to convert photons into electrical charges, reflecting how weak the light source can be. The less light required for an image sensor to collect useful imaging data, the higher its quantum efficiency. In practice, the number of photons can be calculated from parameters such as exposure time difference, actual optical power, and pixel size, while the number of electrons can be obtained from the mean difference of the image density (DN) and the conversion gain. Except for the exposure time difference and the mean difference of the image DN (sensor's output brightness value), the other parameters can be directly measured. Given the strong correlation between the mean difference of image density (DN) and the exposure time difference, and considering the linearity constraints often present in the selection of exposure time, the key to calculating QE lies in obtaining an exposure time that meets the linearity requirements. However, not all exposure times can achieve this. Specifically, due to the influence of dark current, noise interference, and whether charge has reached saturation, it cannot be guaranteed that the image sensor is in the linear region. Furthermore, the response capability to the light field varies for different test bands, sensor types, and processes, making it impossible to guarantee that the exposure time will always meet the linearity requirements. Therefore, it is impossible to accurately measure the quantum efficiency of the image sensor. Thus, there is an urgent need to provide a scheme for measuring the quantum efficiency of image sensors to improve upon these problems. Summary of the Invention

[0003] The purpose of this invention is to provide a method for searching exposure time and a quantum efficiency measurement system, for accurately searching for exposure time that meets linearity requirements, thereby accurately measuring the quantum efficiency of an image sensor.

[0004] Secondly, the present invention provides a method for searching exposure time, the method comprising: configuring fixed parameters of the image acquisition module, the fixed parameters including minimum image mean difference, search step size, initial exposure time value and saturation correction coefficient, and configuring the wavelength of the wavelength configuration device; controlling the image acquisition module to determine a set of candidate exposure times according to the search step size and the initial exposure time value; after the wavelength of the wavelength configuration device is configured, receiving single-band light configured by the wavelength configuration device through an optical fiber bundle; selecting target exposure times multiple times from the set of candidate exposure times; capturing images multiple times under the current wavelength of the wavelength configuration device; determining that the images have not experienced light cutoff and meet preset image saturation constraint conditions and image linearity constraint conditions; then using the target exposure time as a set of exposure times searched corresponding to the current wavelength of the wavelength configuration device, until a set of exposure times corresponding to the wavelengths of each wavelength configuration device is found, and a set of exposure times includes three target exposure times.

[0005] The beneficial effects of the method for searching exposure time provided by this invention are as follows: This embodiment avoids unnecessary search processes by adding cutoff constraints, saturation constraints, and linear constraints. Furthermore, the iterative correction of the search step size and exposure time ensures that the search process steadily progresses towards meeting linearity requirements, greatly improving search efficiency. In addition, this embodiment, combined with relevant data processing modules and other hardware devices, can automate the quantum efficiency testing process. Therefore, this embodiment no longer requires manually configuring exposure times to obtain a set of exposure times corresponding to the wavelengths of each wavelength configuration device that meet linearity requirements. It can be directly applied to an automated quantum efficiency testing system, greatly improving testing efficiency.

[0006] Optionally, the image acquisition module selects a target exposure time multiple times from the set of candidate exposure times, captures images multiple times under the current wavelength of the wavelength configuration device, and determines that the image does not experience light cutoff and meets preset image saturation and linearity constraints. If the image meets these constraints, the target exposure time is selected as a set of exposure times corresponding to the current wavelength of the wavelength configuration device. This process continues until a set of exposure times corresponding to the wavelengths of each wavelength configuration device is found. Each set of exposure times includes three target exposure times:

[0007] The image acquisition module repeatedly executes the search process until a set of exposure times corresponding to the current wavelength of the wavelength configuration device is determined from the set of candidate exposure times. Then, the data processing module reconfigures the wavelength of the wavelength configuration device and re-executes the search process until a set of exposure times corresponding to the wavelengths of each wavelength configuration device is found. The search process includes:

[0008] A second set of target exposure times is determined from the set of candidate exposure times. The second set of target exposure times includes a first target exposure time, a second target exposure time, and a third target exposure time. The difference between the first target exposure time, the third target exposure time, and the second target exposure time is the search step size. The first target exposure time is used as the reference time.

[0009] Acquire a first image generated at a first target exposure time, a second image generated at a second target exposure time, and a third image generated at a third exposure time. Obtain the image mean of the first image, the image mean of the second image, and the image mean of the third image, as well as the image mean at the maximum and minimum exposure times. Calculate the difference between the image mean values ​​at the maximum and minimum exposure times. Determine if the difference satisfies the light cutoff constraint, and if the image mean values ​​of the second and third images satisfy the image saturation and image linearity constraints. Then, use the second set of target exposure times as the set of exposure times searched that correspond to the wavelength of the current wavelength configuration device.

[0010] Optionally, if the image acquisition module determines that the image mean difference satisfies the light cutoff constraint, and the image mean of the second image and the image mean of the third image satisfy the image saturation constraint and the image linearity constraint, then the second pair of exposure times is used as a set of exposure times searched and corresponding to the wavelength of the current wavelength configuration device, including:

[0011] When the difference between the image mean values ​​at the maximum and minimum exposure times satisfies the light cutoff constraint, it is determined whether the image mean values ​​of the second and third images are less than or equal to a set image saturation threshold. When they are less than or equal to the set image saturation threshold, it is determined whether the linearity of the difference between the image mean values ​​of the second and third images falls within a set linear range. If so, the second pair of exposure times is used as a set of exposure times that are searched and correspond to the wavelength of the current wavelength configuration device.

[0012] Optionally, controlling the image acquisition module to determine whether the difference between the image mean values ​​at the maximum and minimum exposure times satisfies the light cutoff constraint includes: acquiring the mean values ​​of each channel at the maximum and minimum exposure times; calculating the difference between the image mean values ​​of each channel at the maximum and minimum exposure times; and determining that the difference between the mean values ​​of each channel has not reached the image cutoff state.

[0013] Optionally, if the linearity of the difference between the image mean of the second image and the linearity of the image mean of the third image do not fall within the set linear interval, the image acquisition module is controlled to reduce the search step size or reduce the first exposure time before returning to the execution of determining the third set of target exposure times from the set of candidate exposure times.

[0014] Optionally, the set image saturation threshold is approximately equal to the image saturation value.

[0015] Optionally, after obtaining the three sets of exposure times, the image acquisition module further includes:

[0016] The data processing module calculates the quantum efficiency based on three sets of exposure times corresponding to the wavelength of each wavelength configuration device.

[0017] Thirdly, the present invention provides a quantum efficiency measurement system, which includes a data processing module, an image acquisition module, and a wavelength configuration device.

[0018] The data processing module is used to configure the fixed parameters of the image acquisition module. The fixed parameters include the minimum image mean difference, the search step size, the initial exposure time, and the saturation correction coefficient.

[0019] The data processing module is also used to configure the wavelength of the wavelength configuration device;

[0020] The image acquisition module receives control commands from the data processing module, determines a set of candidate exposure times based on the search step size and the initial exposure time value, receives single-band light configured by the wavelength configuration device via an optical fiber bundle, selects target exposure times multiple times from the set of candidate exposure times, captures images multiple times under the current wavelength of the wavelength configuration device, determines whether the images have experienced light cutoff and meet preset image saturation and linearity constraints, and then uses the target exposure time as a set of exposure times corresponding to the current wavelength of the wavelength configuration device, until a set of exposure times corresponding to the wavelengths of each wavelength configuration device is found. Each set of exposure times includes three target exposure times.

[0021] Optionally, the image acquisition module is specifically used for:

[0022] The image acquisition module repeatedly executes the search process until a set of exposure times corresponding to the current wavelength of the wavelength configuration device is determined from the set of candidate exposure times. Then, the data processing module reconfigures the wavelength of the wavelength configuration device and re-executes the search process until three sets of exposure times are obtained. The search process includes:

[0023] A second set of target exposure times is determined from the set of candidate exposure times. The second set of target exposure times includes a first target exposure time, a second target exposure time, and a third target exposure time. The difference between the first target exposure time, the third target exposure time, and the second target exposure time is the search step size. The first target exposure time is used as the reference time.

[0024] Acquire a first image generated at a first target exposure time, a second image generated at a second target exposure time, and a third image generated at a third exposure time. Acquire the image mean of the first image, the image mean of the second image, and the image mean of the third image, as well as the image mean at the maximum and minimum exposure times. Calculate the difference between the image mean values ​​at the maximum and minimum exposure times. Determine if the difference satisfies the light cutoff constraint, and if the image mean values ​​of the second and third images satisfy the image saturation and image linearity constraints. If so, use the second set of target exposure times as the set of exposure times searched and corresponding to the wavelength of the current wavelength configuration device. Otherwise, return to the previous step to determine the third set of target exposure times from the set of candidate exposure times.

[0025] The data processing module is also used to calculate the quantum efficiency based on the three sets of exposure times.

[0026] Optionally, if the linearity of the image mean difference of the second image and the image mean of the third image does not fall within the set linear interval, the image acquisition module is further configured to: reduce the search step size or reduce the first exposure time before returning to perform the determination of the third set of target exposure times from the set of candidate exposure times.

[0027] Thirdly, the present invention also provides a computer-readable storage medium comprising a computer program that, when executed, causes the data processing module to perform the method described in any embodiment of the second aspect. Attached Figure Description

[0028] Figure 1 A schematic diagram of the architecture of the quantum efficiency measurement system provided by the present invention;

[0029] Figure 2 This invention provides a flowchart illustrating a method for searching exposure time.

[0030] Figure 3 A schematic diagram of the search step size determination method provided by the present invention;

[0031] Figure 4A schematic diagram of the specific method for determining whether the mean difference of an image satisfies the light cutoff condition provided by the present invention;

[0032] Figure 5 A schematic diagram illustrating the specific method for determining whether the mean difference of an image satisfies the image saturation condition provided by the present invention.

[0033] Figure 6 This is a schematic diagram illustrating the specific method for determining whether the mean difference of an image satisfies the linearity constraint conditions provided by the present invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art. The terms "comprising" and similar expressions used herein mean that the element or object preceding the word covers the element or object listed following the word and its equivalents, but do not exclude other elements or objects.

[0035] like Figure 1 As shown in the diagram, the quantum efficiency measurement system architecture mainly consists of a data processing module 100, a light source 400, a wavelength configuration device 200, and an image acquisition module 300.

[0036] The data processing module 100 is used to configure the fixed parameters of the image acquisition module. The fixed parameters include the minimum image mean difference, the search step size, the initial value of the exposure time, and the saturation correction coefficient.

[0037] The data processing module 100 is also used to configure the wavelength of the wavelength configuration device.

[0038] The light source can be a xenon lamp, used to generate a broadband light source.

[0039] The wavelength configuration device 200 is used to configure a broadband light source input to the wavelength configuration device 200 to generate single-band light. The wavelength configuration device can be a monochromator.

[0040] The image acquisition module 300 receives control commands from the data processing module and determines a set of candidate exposure times based on the search step size and the initial exposure time value. After the wavelength of the wavelength configuration device is configured, it receives the single-band light configured by the wavelength configuration device through an optical fiber bundle, selects the target exposure time multiple times from the set of candidate exposure times, and captures images multiple times under the current wavelength of the wavelength configuration device. If the image does not experience light cutoff and meets the preset image saturation constraint and image linearity constraint, the target exposure time is taken as a set of exposure times corresponding to the current wavelength of the wavelength configuration device. This process continues until a set of exposure times corresponding to the wavelengths of each wavelength configuration device is found. Each set of exposure times includes three target exposure times.

[0041] The data processing module 100 is also used to calculate the quantum efficiency based on three sets of exposure times corresponding to the wavelength of each wavelength configuration device.

[0042] It should be understood that the image acquisition module 300 in this embodiment includes an image sensor, such as a complementary metal-oxide-semiconductor (CMOS) sensor or a charge-coupled device (CCD) sensor. The image sensor is used to sense an image formed by the intensity of red, green, and blue light. The image acquisition module 300 also includes readout electronic circuitry to read the sensed information from the image sensor. Additionally, the image acquisition module 300 includes a memory, such as a dynamic random access memory (DRAM), to store data required during execution, such as fixed parameters, variables, and data tables.

[0043] Based on the above system architecture, specifically, as follows: Figure 2 As shown, the present invention provides a method for searching exposure time, which can be executed by the data processing module of the above system, and the method includes:

[0044] S201, the data processing module configures the fixed parameters of the image acquisition module, the fixed parameters including the minimum image mean difference, search step size, initial exposure time and saturation correction coefficient, and the wavelength of the wavelength configuration device.

[0045] S202, the data processing module controls the image acquisition module to determine a set of candidate exposure times based on the search step size and the initial value of the exposure time. After the wavelength of the wavelength configuration device is configured, the single-band light configured by the wavelength configuration device is received through the optical fiber bundle. The target exposure time is selected multiple times from the set of candidate exposure times. Images are captured multiple times under the current wavelength of the wavelength configuration device. If it is determined that the image has not experienced light cutoff and meets the preset image saturation constraint condition and image linearity constraint condition, then the target exposure time is taken as a set of exposure times corresponding to the current wavelength of the wavelength configuration device. This process continues until a set of exposure times corresponding to the wavelengths of each wavelength configuration device is found. Each set of exposure times includes three target exposure times.

[0046] It should be understood that, for each image captured under the current wavelength, it can be determined whether the image has not experienced light cutoff and meets the preset image saturation constraint and image linearity constraint. If no light cutoff has occurred and the preset image saturation constraint and image linearity constraint are met, then no more images will be captured.

[0047] In S202, the image acquisition module repeatedly executes the search process until a set of exposure times corresponding to the wavelength of the current wavelength configuration device is determined from the set of candidate exposure times. Then, the data processing module reconfigures the wavelength of the wavelength configuration device and re-executes the search process until a set of exposure times corresponding to the wavelengths of each wavelength configuration device is found. The search process includes:

[0048] First, the average image values ​​at the maximum and minimum exposure times are obtained, and the difference between the average image values ​​at the maximum and minimum exposure times is calculated. If the difference between the average image values ​​meets the light cutoff condition, the search stops, and the wavelength of the light is reconfigured. Then, the average image values ​​at the maximum and minimum exposure times are obtained again, and so on, for judgment. If the difference between the average image values ​​does not meet the light cutoff condition, then a second set of target exposure times is determined from the set of candidate exposure times. The second set of target exposure times includes the first target exposure time, the second target exposure time, and the third target exposure time. The difference between the first target exposure time, the third target exposure time, and the second target exposure time is the search step size, and the first target exposure time is used as the reference time. Next, the first image generated at the first target exposure time, the second image generated at the second target exposure time, and the third image generated at the third exposure time are acquired. The average values ​​of the first, second, and third images are obtained. It is determined whether the average values ​​of the second and third images satisfy the image saturation constraint. If the image saturation constraint is not satisfied, the wavelength of the next set of light is configured, and the average values ​​of the images at the maximum and minimum exposure times are re-acquired. This process is repeated. If the image saturation constraint is satisfied, the average values ​​of the first, second, and third images are further determined to satisfy the image linearity constraint. If satisfied, the second set of target exposure times is used as the set of exposure times corresponding to the wavelength of the current wavelength configuration device. If the image linearity constraint is not satisfied, the search step size or the first exposure time is adjusted. If the number of search iterations reaches the maximum threshold or the search step size reaches the minimum threshold, the current search is terminated, and the default array of three exposure times is used as a reference value. Then, the next set of wavelengths is configured, and the search process for the exposure time of the next set of wavelengths begins. This process is repeated. It is worth noting that after finding a set of exposure times that meet the requirements under a certain wavelength, the parameters need to be reset. The parameter reset includes resetting all three exposure time values ​​to their initial values ​​and resetting the search step size to its initial step size.

[0049] It should be understood that the search step size can be based on, for example... Figure 3The method flow shown determines an appropriate value. First, the data processing module configures the exposure time of the image acquisition module to the initial value t0, obtaining the image mean Mean0 = f(t0). Then, the image acquisition module configures the exposure time to the second exposure time t1 = t0 + ExpTimeStep, obtaining the image mean Mean1 = f(t1). The image mean difference MeanDelta0 = Mean1 - Mean0 is calculated, i.e., MeanDelta0 = f(t0 + ExpTimeStep) - f(t0). If the image mean difference MeanDelta0 is less than the minimum mean difference, the search step size ExpTimeStep is multiplied by a correction coefficient. If the image mean difference MeanDelta0 is greater than or equal to the minimum mean difference, then the search step size can be used.

[0050] For example, such as Figure 4 As shown, the specific process for determining whether the image mean difference meets the light cutoff condition includes: First, configuring the exposure time of the image acquisition module to the minimum exposure time, exemplified by 10ms. Then, obtaining the mean values ​​of each image channel. Next, configuring the CIS exposure time to the maximum exposure time, recalculating the mean difference of each channel image, and determining whether the mean difference of each image channel has reached the cutoff value. If not, continuing the search for exposure time; if yes, stopping the search for exposure time under that single-band light. For example, the cutoff value for 10-bit data types is 5DN, the cutoff value for 12-bit data types is 20DN, and the cutoff value for other data types is 10DN.

[0051] Another example is setting an image saturation threshold that approximates the image saturation value. For example... Figure 5 As shown, the specific process for determining whether the image mean meets the image saturation condition includes: First, the data processing module configures the first exposure time of the image acquisition module as the initial value t0, obtaining the image mean Mean0 = f(t0). Then, the image acquisition module configures the second exposure time t1 = t0 + ExpTimeStep, and the third exposure time t2 = t0 + ExpTimeStep, where ExpTimeStep is the current search step size. Next, the second image mean Mean1 = f(t1) and the third image mean Mean2 = f(t2) are obtained. If the maximum value between the second and third image means is less than or equal to 0.95 multiplied by the image saturation value, the search for the exposure time under that single-band light continues; otherwise, the search for the exposure time under that single-band light stops. It is worth noting that 0.95 is an adjustable parameter, and the constraint can be relaxed according to actual needs; this embodiment does not limit this.

[0052] Other possible embodiments, such as Figure 6As shown, the specific process for determining whether the difference in image means satisfies the linearity constraint includes: First, the data processing module configures the exposure time of the image acquisition module as the first exposure time t0, obtaining the first image mean Mean0 = f(t0). Then, the image acquisition module configures the exposure time as the second exposure time t1 = t0 + ExpTimeStep, and the third exposure time t2 = t0 + ExpTimeStep, where ExpTimeStep is the current search step size. Next, the second image mean Mean1 = f(t1) and the third image mean Mean2 = f(t2) are obtained. Finally, the linearity between Mean0, Mean1, and Mean2 is calculated. If the linearity of Mean0, Mean1, and Mean2 does not fall within the set linear interval, for example, if the linearity of the image mean among Mean0, Mean1, and Mean2 is greater than or equal to 1 + linear interval, the value of the updated first exposure time is returned, i.e., t0 = t0 + ExpTimeStep. Otherwise, if the linearity of the image mean among Mean0, Mean1, and Mean2 is less than 1 - linear interval, the search step size is adjusted, i.e., the updated search step size ExpTimeStep, ExpTimeStep = ExpTimeStep / 2, and the second and third exposure times are reconfigured, and then the search for exposure time under this single-band light continues. Alternatively, if the linearity of the image mean among Mean0, Mean1, and Mean2 is less than 1 + linear interval but greater than or equal to 1 - linear interval, the first, second, and third exposure times are used as a set of exposure times for that wavelength. The search for exposure times under other wavelengths under single-band light can then continue or the search can be stopped.

[0053] In summary, the beneficial effects of the method for searching exposure time provided by this invention are as follows: This embodiment avoids unnecessary search processes by adding cutoff constraints, saturation constraints, and linear constraints. Furthermore, the iterative correction of the search step size and exposure time ensures that the search process steadily progresses towards meeting the linearity requirements, greatly improving search efficiency. In addition, this embodiment, combined with relevant data processing modules and other hardware devices, can automate the quantum efficiency testing process. Therefore, this embodiment no longer requires manually configuring exposure times to obtain three sets of exposure times that meet the linearity requirements, and can be directly applied to an automated quantum efficiency testing system, greatly improving testing efficiency.

[0054] While embodiments of the present invention have been described in detail above, it will be apparent to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations fall within the scope and spirit of the invention as set forth in the claims. Furthermore, the invention described herein may have other embodiments and can be implemented or carried out in various ways.

Claims

1. A method for searching exposure time, applied to a data processing module in a quantum efficiency measurement system, the quantum efficiency measurement system comprising a data processing module, an image acquisition module, and a wavelength configuration device, characterized in that, include: Configure the fixed parameters of the image acquisition module, including the minimum image mean difference, search step size, initial exposure time and saturation correction coefficient, and configure the wavelength of the wavelength configuration device; The image acquisition module determines a set of candidate exposure times based on the search step size and the initial value of the exposure time. After the wavelength of the wavelength configuration device is configured, it receives the single-band light configured by the wavelength configuration device through the fiber optic bundle, selects the target exposure time multiple times from the set of candidate exposure times, and captures images multiple times under the current wavelength of the wavelength configuration device. If the image does not experience light cutoff and meets the preset image saturation constraint condition and the image linearity constraint condition, then the target exposure time is used as a set of exposure times corresponding to the current wavelength of the wavelength configuration device. This process continues until a set of exposure times corresponding to the wavelengths of each wavelength configuration device is found. Each set of exposure times includes three target exposure times. The process of determining whether the image meets the preset image saturation constraint conditions includes: the data processing module configures the exposure time of the image acquisition module as the second exposure time and the third exposure time, and obtains the average value of the second image and the average value of the third image accordingly. If the maximum value of the average value of the second image and the average value of the third image is greater than the set image saturation threshold, the search for the exposure time under the single-band light is stopped.

2. The method according to claim 1, characterized in that, The image acquisition module selects a target exposure time multiple times from a set of candidate exposure times, captures multiple images under the current wavelength of the wavelength configuration device, and determines whether the images have not experienced light cutoff and meet preset image saturation and linearity constraints. If so, the target exposure time is selected as a set of exposure times corresponding to the current wavelength of the wavelength configuration device, until a set of exposure times corresponding to the wavelengths of each wavelength configuration device is found. This process continues until a set of exposure times corresponding to the wavelengths of each wavelength configuration device is found, including: The image acquisition module repeatedly executes the search process until a set of exposure times corresponding to the current wavelength of the wavelength configuration device is determined from the set of candidate exposure times. Then, the data processing module reconfigures the wavelength of the wavelength configuration device and re-executes the search process until a set of exposure times corresponding to the wavelengths of each wavelength configuration device is found. The search process includes: A second set of target exposure times is determined from the set of candidate exposure times. The second set of target exposure times includes a first target exposure time, a second target exposure time, and a third target exposure time. The difference between the first target exposure time, the second target exposure time, and the third target exposure time is the search step size. The first target exposure time is used as the reference time. A first image generated at a first target exposure time, a second image generated at a second target exposure time, and a third image generated at a third exposure time are acquired. The image mean of the first image, the image mean of the second image, and the image mean of the third image are acquired, as well as the image mean at the maximum exposure time and the minimum exposure time. The image mean difference between the image mean at the maximum exposure time and the minimum exposure time is calculated. If the image mean difference satisfies the light cutoff constraint, the image mean of the second image and the image mean of the third image satisfy the image saturation constraint, and the image mean of the first image, the image mean of the second image, and the image mean of the third image satisfy the image linearity constraint, then the second set of target exposure times is taken as the set of exposure times searched that correspond to the wavelength of the current wavelength configuration device.

3. The method according to claim 2, characterized in that, The image acquisition module determines that the image mean difference satisfies the light cutoff constraint, and that the image mean of the first image, the image mean of the second image, and the image mean of the third image satisfy the image saturation constraint and the image linearity constraint. Then, the second set of target exposure times is taken as the set of exposure times searched and corresponding to the wavelength of the current wavelength configuration device, including: When the difference between the image mean values ​​at the maximum and minimum exposure times satisfies the light cutoff constraint, it is determined whether the image mean values ​​of the second and third images are less than or equal to a set image saturation threshold. When they are less than or equal to the set image saturation threshold, it is determined whether the linearity of the image mean values ​​of the first, second, and third images falls within a set linear range. If so, the second set of target exposure times is taken as a set of exposure times that corresponds to the wavelength of the current wavelength configuration device.

4. The method according to claim 3, characterized in that, Controlling the image acquisition module to determine whether the difference between the image mean values ​​at the maximum and minimum exposure times satisfies the light cutoff constraint includes: Obtain the average values ​​of each channel at the maximum and minimum exposure times; Calculate the difference between the image mean values ​​at the maximum and minimum exposure times for each channel of the image, and determine whether the difference between the mean values ​​of each channel of the image has reached the image cutoff state.

5. The method according to claim 3, characterized in that, If the linearity of the mean values ​​of the first, second, and third images does not fall within the set linear range, the image acquisition module is controlled to return to the point where it adjusts the search step size and the value of the first target exposure time before continuing to search for the target exposure time.

6. The method according to claim 3, characterized in that, The set image saturation threshold is approximately equal to the image saturation value.

7. The method according to claim 3, characterized in that, After the image acquisition module obtains a set of exposure times corresponding to the wavelengths of each wavelength configuration device, it also includes: The data processing module calculates the quantum efficiency based on a set of exposure times corresponding to the wavelength of each wavelength configuration device.

8. A quantum efficiency measurement system, characterized in that, The quantum efficiency measurement system includes a data processing module, an image acquisition module, and a wavelength configuration device; The data processing module is used to configure the fixed parameters of the image acquisition module. The fixed parameters include the minimum image mean difference, the search step size, the initial value of the exposure time, and the saturation correction coefficient. The data processing module is also used to configure the wavelength of the wavelength configuration device; The image acquisition module receives control commands from the data processing module, determines a set of candidate exposure times based on the search step size and the initial exposure time value, and receives single-band light configured by the wavelength configuration device through an optical fiber bundle after the wavelength configuration device has been configured. It selects a target exposure time multiple times from the set of candidate exposure times, captures images multiple times under the current wavelength of the wavelength configuration device, and determines if the image does not experience light cutoff and meets preset image saturation and linearity constraints. If so, the target exposure time is selected as a set of exposure times corresponding to the current wavelength of the wavelength configuration device, until a set of exposure times corresponding to the wavelengths of each wavelength configuration device is found. Each set of exposure times includes three target exposure times. The process of determining if the image meets the preset image saturation constraints includes: the data processing module configures the exposure time of the image acquisition module as a second and third exposure time, and obtains the average value of the second and third images accordingly. If the maximum value of the second and third image averages is greater than a set image saturation threshold, the search for the exposure time under that single-band light is stopped.

9. The system according to claim 8, characterized in that, The image acquisition module is specifically used for: The image acquisition module repeatedly executes the search process until a set of exposure times corresponding to the current wavelength of the wavelength configuration device is determined from the set of candidate exposure times. Then, the data processing module reconfigures the wavelength of the wavelength configuration device and re-executes the search process until a set of exposure times corresponding to the wavelengths of each wavelength configuration device is found. The search process includes: A second set of target exposure times is determined from the set of candidate exposure times. The second set of target exposure times includes a first target exposure time, a second target exposure time, and a third target exposure time. The difference between the first target exposure time, the third target exposure time, and the second target exposure time is the search step size. The first target exposure time is used as the reference time. Acquire a second image generated at the second target exposure time and a third image generated at the third exposure time; acquire the image mean of the second image and the image mean of the third image; acquire the image mean at the maximum exposure time and the minimum exposure time; calculate the difference between the image mean at the maximum exposure time and the minimum exposure time; determine if the difference between the image mean satisfies the light cutoff constraint condition, and if the image mean of the second image and the image mean of the third image satisfy the image saturation constraint condition and the image linearity constraint condition, then take the second set of target exposure times as the set of exposure times searched that corresponds to the wavelength of the current wavelength configuration device; The data processing module is also used to calculate the quantum efficiency of the image acquisition module at the wavelength of each wavelength configuration device according to a set of exposure times corresponding to the wavelengths of each wavelength configuration device.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the method of any one of claims 1 to 7.

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