A method, device, equipment and medium for detecting a photosensitive chip

Abstract

The present invention discloses a method, device, equipment and medium for detecting a photosensitive chip, including: obtaining N pictures taken by the photosensitive chip to be detected under preset conditions, where the exposure times of the N pictures are different; determining a first correlation relationship between the brightness value and the exposure time of each picture, and a second correlation relationship between the brightness values and the exposure times among the N pictures; if the deviation degree between the first correlation relationship and the second correlation relationship corresponding to at least M pictures among the N pictures is greater than a first preset threshold, determining that the photosensitive chip to be detected is unqualified. The present invention determines the first correlation relationship between the brightness value and the exposure time in each picture, and the second correlation relationship between the brightness values and the exposure times among the N pictures, and determines whether the brightness value and the exposure time of the photosensitive chip to be detected meet the requirements based on the deviation degree between the first correlation relationship and the second correlation relationship, that is, determines whether the photosensitive chip to be detected is qualified.

Description

Technical Field

[0001] The present invention relates to the technical field of photosensitive chips, and in particular, to a method, device, equipment and medium for detecting a photosensitive chip. Background Art

[0002] A camera module is a crucial electronic device for image capture, which can convert the optical signal of an object into a digital signal that can be read and stored, and mainly includes components such as a lens, a photosensitive chip, a motor, a filter, a circuit board, and a base. Among them, a photosensitive chip (which can also be called an image sensor chip) is the core device of the camera module, mainly used for sensing light and generating a digital picture through photoelectric conversion.

[0003] For a photosensitive chip, the more light the chip receives (for example, the longer the exposure time), the brighter the captured picture. However, how to determine whether the current chip is qualified based on the exposure time and brightness of the picture captured by the chip is an urgent problem to be solved. Summary of the Invention

[0004] Embodiments of the present application provide a method, device, equipment and medium for detecting a photosensitive chip, solve the technical problem in the prior art that it is impossible to determine whether the current chip is qualified based on the exposure time and brightness of the picture captured by the chip, and achieve the technical effect of identifying whether the current chip is qualified based on the exposure time and brightness of the picture captured by the chip.

[0005] In a first aspect, the present application provides a method for detecting a photosensitive chip, and the method includes:

[0006] Obtain N pictures captured by the photosensitive chip to be tested under preset conditions, and the exposure times of the N pictures are different; N is a positive integer greater than or equal to 2;

[0007] Determine the first correlation relationship between the brightness value and the exposure time of each picture, and the second correlation relationship between the brightness values and the exposure times among the N pictures;

[0008] If the deviation degree between the first correlation relationship and the second correlation relationship corresponding to at least M pictures among the N pictures is greater than a first preset threshold, determine that the photosensitive chip to be tested is unqualified; M is a positive integer less than or equal to N and greater than or equal to 1.

[0009] Further, during the process of the photosensitive chip to be tested capturing N pictures or before capturing N pictures, the method further includes:

[0010] According to the maximum exposure time of the photosensitive chip to be tested, determine the exposure time corresponding to each of the N pictures when the photosensitive chip to be tested captures the N pictures.

[0011] Further, before determining the first correlation relationship between the brightness value and the exposure time of each picture, the method further includes:

[0012] According to the detection requirements of the photosensitive chip to be tested, a target area is delimited in each picture;

[0013] According to the brightness value of the target area of each picture, determine the brightness value of each picture.

[0014] Furthermore, the target area of each picture is the central area.

[0015] Furthermore, determine the first correlation relationship between the brightness value and the exposure time of each picture, including:

[0016] According to the brightness value and exposure time of each picture, and the dark current value of the photosensitive chip to be tested, determine the first correlation relationship between the brightness value and the exposure time in each picture, and the first correlation relationship is related to the linear relationship.

[0017] Furthermore, determine the second correlation relationship between the brightness value and the exposure time among N pictures, including:

[0018] Fit the brightness value and exposure time among N pictures, and determine the second correlation relationship between the brightness value and the exposure time among N pictures, and the second correlation relationship is related to the linear relationship.

[0019] Furthermore, after obtaining N pictures, the method further includes:

[0020] Identify the target type channel of each picture;

[0021] Determine the third correlation relationship between the brightness value and the exposure time of the target type channel of each picture, and the fourth correlation relationship between the brightness value and the exposure time of the target type channel among N pictures;

[0022] If the deviation degree between the third correlation relationship and the fourth correlation relationship corresponding to the target type channel of at least P pictures among N pictures is greater than the second preset threshold, determine that the photosensitive chip to be tested is unqualified; P is a positive integer less than or equal to N and greater than or equal to 1.

[0023] In a second aspect, the present application provides a photosensitive chip detection device, the device includes:

[0024] A picture acquisition module, configured to acquire N pictures obtained by photographing the photosensitive chip to be tested under preset conditions, and the exposure times of the N pictures are different; N is a positive integer greater than or equal to 2;

[0025] A relationship determination module, configured to determine the first correlation relationship between the brightness value and the exposure time of each picture, and the second correlation relationship between the brightness value and the exposure time among N pictures;

[0026] A judgment module, configured to determine that the photosensitive chip to be tested is unqualified if the deviation degree between the first correlation relationship and the second correlation relationship corresponding to at least M pictures among N pictures is greater than a first preset threshold; M is a positive integer less than or equal to N and greater than or equal to 1.

[0027] In a third aspect, the present application provides an electronic device, including:

[0028] A processor;

[0029] A memory for storing executable instructions of the processor;

[0030] Wherein, the processor is configured to execute to implement a photosensitive chip detection method provided in the first aspect.

[0031] In a fourth aspect, the present application provides a non-transitory computer-readable storage medium, when the instructions in the storage medium are executed by the processor of the electronic device, enabling the electronic device to execute and implement a photosensitive chip detection method provided in the first aspect.

[0032] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0033] In the embodiments of the present application, by processing N pictures taken by the photosensitive chip to be tested, the first correlation relationship between the brightness value and the exposure time in each picture is determined, and the second correlation relationship between the brightness values and the exposure time among the N pictures is determined. Based on the deviation degree between the first correlation relationship and the second correlation relationship, it is determined whether the brightness value and the exposure time of the photosensitive chip to be tested meet the requirements, that is, it is determined whether the photosensitive chip to be tested is qualified. Using this method to detect the photosensitive chip before it leaves the factory can improve the stability of the photosensitive chip during subsequent use and improve the sensitivity of the photosensitive chip to brightness and exposure time. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0035] Figure 1 It is a schematic flowchart of a photosensitive chip detection method provided by the present application;

[0036] Figure 2 It is a schematic diagram of the target area determined in the picture in the present application;

[0037] Figure 3 It is a schematic diagram of the channel distribution of the pictures taken by a certain model of photosensitive chip in the present application;

[0038] Figure 4 It is a schematic diagram of the target area determined in the picture corresponding to the R channel in this application;

[0039] Figure 5 It is a schematic diagram of the relationship between the brightness value and the exposure time among 33 pictures corresponding to the R channel in this application;

[0040] Figure 6 It is a schematic diagram of the structure of a photosensitive chip detection device provided by this application;

[0041] Figure 7 It is a schematic diagram of the structure of an electronic device provided by this application. Specific embodiments

[0042] By providing a photosensitive chip detection method in the embodiments of this application, the technical problem in the prior art that it is impossible to determine whether the current chip is qualified based on the exposure time and brightness of the pictures taken by the chip is solved.

[0043] The technical solution of the embodiments of this application to solve the above technical problem is generally as follows:

[0044] A photosensitive chip detection method, the method includes: obtaining N pictures taken by a photosensitive chip to be measured under preset conditions, and the exposure times of the N pictures are different; N is a positive integer greater than or equal to 2; determining the first correlation relationship between the brightness value and the exposure time of each picture, and the second correlation relationship between the brightness values and the exposure times among the N pictures; if the deviation degree between the first correlation relationship and the second correlation relationship corresponding to at least M pictures among the N pictures is greater than the first preset threshold, determining that the photosensitive chip to be measured is unqualified; M is a positive integer less than or equal to N and greater than or equal to 1.

[0045] In the embodiments of this application, by processing N pictures taken by the photosensitive chip to be measured, the first correlation relationship between the brightness value and the exposure time in each picture and the second correlation relationship between the brightness values and the exposure times among the N pictures are determined. Based on the deviation degree between the first correlation relationship and the second correlation relationship, it is determined whether the brightness value and the exposure time of the photosensitive chip to be measured meet the requirements, that is, it is determined whether the photosensitive chip to be measured is qualified. Using this method to detect the photosensitive chip before it leaves the factory can improve the stability of the photosensitive chip during subsequent use and improve the sensitivity of the photosensitive chip to brightness and exposure time.

[0046] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings of the specification and specific embodiments.

[0047] First, it should be noted that the term "and / or" appearing in this article is merely a description of the association relationship between associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. Additionally, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0048] This application provides a Figure 1 photosensitive chip detection method as shown below. The method includes:

[0049] Step S11: Obtain N pictures taken by the photosensitive chip to be tested under preset conditions, where the exposure times of the N pictures are different; N is a positive integer greater than or equal to 2.

[0050] Step S12: Determine the first association relationship between the brightness value and the exposure time of each picture, and the second association relationship between the brightness values and the exposure times among the N pictures.

[0051] Step S13: If the deviation degree between the first association relationship and the second association relationship corresponding to at least M pictures among the N pictures is greater than the first preset threshold, determine that the photosensitive chip to be tested is unqualified; M is a positive integer less than or equal to N and greater than or equal to 1.

[0052] Regarding step S11, obtain N pictures taken by the photosensitive chip to be tested under preset conditions, where the exposure times of the N pictures are different; N is a positive integer greater than or equal to 2.

[0053] When taking N pictures with the photosensitive chip to be tested, the photosensitive chip to be tested can be placed under preset conditions for shooting. The preset conditions can include environmental parameters and chip parameters.

[0054] Among them, the environmental parameters can include light source model, light source color temperature, and light source brightness.

[0055] Under normal circumstances, the light source model can be a uniform flat light source. The uniform flat light source has a good planar light-emitting effect, enabling the light source to cover the photosensitive range of the photosensitive chip to be tested. All N pictures obtained by using the photosensitive chip to be tested to shoot the uniform flat light source can be pure white pictures. Using the uniform flat light source can make the brightness of the pictures taken by the photosensitive chip uniform, thereby avoiding large brightness differences in different parts of the pictures, reducing the contingency of the calculated brightness values in the subsequent steps of calculating the picture brightness, and accurately reflecting the photosensitive situation of the chip.

[0056] The light source color temperature can be selected according to the color temperature of natural light. For example, 5100K close to natural light can be adopted. Under the condition of natural sunlight on a sunny day, the color temperature is approximately 5100K. Using the photosensitive chip to shoot at a color temperature of 5100K can make the photosensitive chip more conform to the actual usage scenario.

[0057] The light source brightness in this embodiment refers to the brightness of the picture obtained by the photosensitive chip after shooting under a certain exposure time, and can also be called the pixel value or grayscale value of the picture. Generally, the longer the exposure time of the photosensitive chip, the more light the photosensitive chip receives, and the brighter the captured picture (i.e., the larger the pixel value). The light source brightness when the photosensitive chip under test reaches light saturation at the maximum exposure time is denoted as the limit brightness of the photosensitive chip under test. The light source brightness can be any brightness value less than or equal to the limit brightness, and can be specifically selected according to the actual situation. The photosensitive chip under test reaching light saturation means that as the amount of light received by the photosensitive chip under test increases, the output image brightness no longer changes. For example, the maximum exposure time of a certain photosensitive chip is 33 ms, and the limit brightness corresponding to the picture taken in the continuous exposure state of 33 ms is 1023 (i.e., 2 10 -1).

[0058] Of course, in the actual operation process, the environmental parameters can be adjusted according to the different parameters of the photosensitive chip under test, and this embodiment does not limit this.

[0059] The parameters of the photosensitive chip can include digital gain, analog gain, and exposure time.

[0060] The digital gain mainly adjusts the pulse amplitude input to the digital-to-analog conversion. If its value is too small, the increase in lost error codes will be caused; however, if the amplitude is too large, due to severe clipping of the data pulse and the increase in noise pulses, the signal-to-noise ratio of the digital signal will also deteriorate, and the increase in interference error codes will also be caused. The digital gain can be adjusted according to the different parameters of the photosensitive chip under test, and this embodiment does not limit this. For example, for a certain photosensitive chip, its corresponding digital gain can be set to 1 times.

[0061] The analog gain mainly adjusts the signal strength of the linearly amplified input, and its magnitude affects the value of the output power. Within a certain range, a larger input value is beneficial to improving the output signal-to-noise ratio, and the output power will also increase proportionally. However, when the input is too large, the increase in the output power becomes slow, and the distortion rises sharply. The analog gain can be adjusted according to the different parameters of the photosensitive chip under test, and this embodiment does not limit this. For example, for a certain photosensitive chip, the analog gain can be set to the maximum magnification of the photosensitive chip under test (such as 8 times).

[0062] The exposure time can be determined according to the maximum exposure time of the photosensitive chip under test, and can specifically be any exposure time less than or equal to the maximum exposure time. For example, the maximum exposure time of a certain photosensitive chip under test is 33 ms, and the exposure time selected when taking pictures can be any exposure time less than or equal to 33 ms. For example, it can be 1 ms, 1.4 ms, 3 ms, 8 ms, 33 ms, etc., and this embodiment does not limit this.

[0063] For this embodiment, when using the photosensitive chip to be tested to take N pictures, the exposure time corresponding to each picture is different, and the exposure time of each picture does not exceed the maximum exposure time of the photosensitive chip to be tested. That is to say, during the process of using the photosensitive chip to be tested to take N pictures or before taking N pictures, the exposure time corresponding to each of the N pictures when using the photosensitive chip to be tested to take N pictures can be determined according to the maximum exposure time of the photosensitive chip to be tested. As long as the exposure times of the N pictures are not equal to each other, the relationship between the exposure times of the N pictures can be a regular sequence (such as an arithmetic sequence) or an irregular sequence.

[0064] For example, according to the exposure times of the N pictures respectively, the N pictures are sorted in ascending order. The exposure times of the sorted N pictures can be an arithmetic sequence or a non - arithmetic sequence, and can be specifically set according to the actual situation.

[0065] When the maximum exposure time of the photosensitive chip to be tested is 33 ms and N is 33, when the exposure times of the 33 sorted pictures are an arithmetic sequence, the exposure times can be: 1 ms, 2 ms... 32 ms, 33 ms in sequence, or can also be: 0.5 ms, 1.5 ms... 31.5 ms, 32.5 ms in sequence.

[0066] When the maximum exposure time of the photosensitive chip to be tested is 33 ms and N is 33, when the exposure times of the 33 sorted pictures are a non - arithmetic sequence, the exposure times can be: 1 ms, 1.5 ms, 2.5 ms, 2.6 ms... 29 ms, 30 ms in sequence (where the ellipsis indicates that the exposure times can be arbitrarily taken in ascending order, and will not be further described here).

[0067] It should be noted that when using the photosensitive chip to be tested to take N pictures, the pictures can be taken in ascending order of exposure time, or can be taken in other orders, and this embodiment does not limit this. In addition, the exposure times of all pictures can be determined before starting to take N pictures, or during the shooting process, and the corresponding picture can be taken after determining each exposure time, and this embodiment also does not limit this.

[0068] Generally speaking, within the maximum exposure time, at least two pictures with unequal exposure times need to be taken (that is, N is an integer greater than or equal to 2). If only one picture is taken or there are more than two pictures but the exposure times are exactly the same, the effect of the detection method provided in this embodiment is not obvious.

[0069] Regarding step S12, determine the first correlation relationship between the brightness value of each picture and the exposure time, and the second correlation relationship between the brightness values of the N pictures and the exposure time.

[0070] First, the brightness value of each image can be determined first.

[0071] When determining the brightness value of each image, it can be determined according to the brightness value corresponding to any area on the image. For example, it can be the average value of all pixel values in the image, or the brightness value corresponding to a partial area in the image. This embodiment does not limit this.

[0072] When the brightness value of each image is represented by the brightness value corresponding to a partial area, the following method can be adopted: according to the detection requirements of the photosensitive chip to be measured, a target area is delimited in each image; according to the brightness value of the target area of each image, the brightness value of each image is determined.

[0073] The detection requirements can usually be efficiency, accuracy, etc. When the detection requirements tend to be higher efficiency, then a smaller area can be delimited as the target area in each image, and the brightness value in the smaller target area is calculated, and its calculation efficiency is faster, so the determination efficiency of the brightness value of each image is also faster. That is to say, when the detection requirements tend to be higher efficiency, the smaller the area of the selected target area, the higher the efficiency, and relatively, the accuracy will decrease.

[0074] When the detection requirements tend to be higher accuracy, then a larger area can be delimited as the target area in each image, and the brightness value in the larger target area is calculated, and its accuracy is higher, so the accuracy of the brightness value of each image is also higher. That is to say, when the detection requirements tend to be higher accuracy, the larger the area of the selected target area, the higher the accuracy, and relatively, the detection efficiency will decrease. In actual operation, the weight between accuracy and efficiency can be balanced according to actual needs to determine the area size of the target area.

[0075] In addition, for each image, the closer the target area is to the central area (the central area refers to the area near the geometric center of the image and including the geometric center), the more uniform its brightness, and the calculated brightness value can better reflect the shooting effect of the photosensitive chip to be measured, that is, the determination accuracy of the photosensitive chip to be measured will be higher. The closer the target area is to the edge area of the image, the lower its calculation accuracy. The reason is that due to the influence of the physical characteristics of the lens, the central area of the captured test image is the clearest, and the clarity gradually decreases towards the surrounding areas. Calculating the brightness value according to the image parameters of the central area will be more accurate. Therefore, when determining the target area of each image, the central area of each image can be included in the target area for calculating the brightness value.

[0076] For example, referring to Figure 2 , the length of a certain captured image is a, the width is b, and the geometric center is o. The area including the geometric center (i.e.,Figure 2 The area delimited by the inner box in the [figure] is used as the target area. The length of the target area is c (assuming c is 1 / 3 of a), and the width is d (assuming d is 1 / 3 of b). When calculating the brightness value of this picture, the average value of the brightness of all pixels in the target area can be calculated, and this average value is used as the brightness value of this picture. For the specific calculation of the average brightness value of the target area, reference can be made to the related technology, which will not be elaborated here.

[0077] Then, after determining the brightness value of each picture, the first correlation relationship between the brightness value of each picture and the exposure time is determined. Among them, the first correlation relationship can be simplified to a linear relationship, specifically as shown in the following formula (1).

[0078] signal = Slope_ut * exp_time (1)

[0079] Where signal is the brightness value of the current picture, exp_time is the exposure time corresponding to the current picture during shooting, and Slope_ut is the first correlation relationship between the brightness value of the current picture and the exposure time.

[0080] Preferably, during the actual process of the photosensitive chip taking pictures, dark current will also be generated. Therefore, when determining the first correlation relationship, the first correlation relationship between the brightness value and the exposure time in each picture can also be determined according to the brightness value and the exposure time of each picture, as well as the dark current value of the photosensitive chip to be measured. The first correlation relationship is related to the linear relationship. Then, the relationship between the brightness value and the exposure time of each picture can be expressed by the following formula (2).

[0081] signal = Slope_ut * exp_time + black_level (2)

[0082] Where signal is the brightness value of the current picture, black_level is the dark current value corresponding to the photosensitive chip when taking pictures, exp_time is the exposure time corresponding to the current picture during shooting, and Slope_ut is the slope, which represents the first correlation relationship between the brightness value of the current picture and the exposure time.

[0083] Among them, the dark current generally refers to the amount of current released by a photodiode in the absence of incident light. In this embodiment, the dark current also refers to the picture brightness value output by the photosensitive chip in the absence of light. For an ideal photosensitive chip, its dark current value should be zero. However, in actual situations, the photodiode in each pixel also acts as a capacitor at the same time. When the capacitor slowly discharges the charge, even without incident light, the voltage of the dark current will be equivalent to the output voltage of low-brightness incident light. Therefore, in actual operation, the dark current value of each photosensitive chip is a small fixed value. The fixed value corresponding to each photosensitive chip can be obtained through query or testing.

[0084] Finally, according to the brightness values and exposure times of each picture, the second correlation relationship between the brightness values and exposure times among N pictures is determined. Specifically, by fitting the brightness values and exposure times among N pictures, the second correlation relationship between the brightness values and exposure times among N pictures is determined, and the second correlation relationship is related to the linear relationship.

[0085] Generally, the longer the exposure time, the more light the photosensitive chip receives, and the brighter the captured picture. Then, among the N captured pictures, when the exposure time is larger, the corresponding picture brightness value should be larger. Specifically, the second correlation relationship between the brightness values and exposure times among N pictures can be expressed by the following formula (3).

[0086] y = Slope_ref * x + b (3)

[0087] Among them, x represents the exposure time, y represents the picture brightness value corresponding to when the exposure time is x, b is a constant; Slope_ref is the reference slope (in order to distinguish the slope here from the slope in the above formula (2), it is denoted as the reference slope), which characterizes the second correlation relationship between the brightness values and exposure times among the current N pictures.

[0088] In actual operation, the least squares method can be used to fit the brightness values and exposure times among N pictures. The least squares method can find the best function matching of the data by minimizing the sum of the squares of the errors. Of course, in actual operation, other fitting methods can also be used, and this embodiment does not limit this.

[0089] Regarding step S13, if the deviation degree between the first correlation relationship and the second correlation relationship corresponding to at least M pictures among N pictures is greater than the first preset threshold, it is determined that the photosensitive chip to be tested is unqualified; M is a positive integer less than or equal to N and greater than or equal to 1.

[0090] The first correlation relationship of each image can be a linear relationship between the brightness value and the exposure time, which can be specifically represented by the slope, specifically referring to Formula (2); the second correlation relationship of N images can be a linear relationship between the brightness values and exposure times among the N images, which can be specifically represented by the reference slope, specifically referring to Formula (3). The deviation degree is used to represent the deviation between the slope of each image and the reference slope, which can be specifically represented by Formula (4).

[0091]

[0092] Among them, Linearity_error represents the deviation degree (a positive number or 0), Slope_ut represents the slope of any one of the N images, and Slope_ref represents the reference slope formed by the N images.

[0093] Generally speaking, the first preset threshold can be obtained according to the parameters of the model to which the current photosensitive chip to be tested belongs. More preferably, the first preset threshold can also be obtained by statistically analyzing the chip characteristics of the model to which the current photosensitive chip to be tested belongs, which can make the obtained first preset threshold more in line with the detection characteristics of the photosensitive chip to be tested and improve the detection accuracy of the photosensitive chip to be tested.

[0094] For example, during actual operation, the above steps S11 - S12 can be performed on any batch of Model A chips in the production process (denote the model to which the current photosensitive chip to be tested belongs as Model A) to determine the first correlation relationship and the second correlation relationship corresponding to each chip in the first batch, and then determine the deviation degree between each first correlation relationship and the second correlation relationship (for the sake of distinction, denote the deviation degree here as the linearity error). The upper limit linearity error can be determined according to the linearity error of each obtained chip. The upper limit linearity error can be an error value for distinguishing whether a chip can be used normally. For example, the upper limit linearity error of a certain model of chip is 20%. When the linearity error of a certain chip to be tested is less than or equal to 20%, the chip to be tested can be used normally; if the linearity error of a certain chip to be tested is greater than 20%, the chip cannot be used normally.

[0095] After determining the upper limit linearity error, any value (positive number or 0) less than or equal to the upper limit linearity error can be determined as the first preset threshold, and the first preset threshold is a parameter for judging whether the chip is qualified (whether it is qualified can refer to whether it can be normally manufactured and sold). In actual operation, the first preset threshold can also be determined according to the detection strictness of the photosensitive chip to be measured. For example, when the detection strictness is higher, the selected first preset threshold is farther away from the upper limit linearity error; when the detection strictness is lower, the selected first preset threshold is closer to the upper limit linearity error. That is to say, the closer the selected first preset threshold is to the upper limit linearity error, the lower the linearity of the chip detected by the first preset threshold; the farther the selected first preset threshold is from the upper limit linearity error, the higher the linearity of the chip detected by the first preset threshold. After obtaining the first preset threshold, for the photosensitive chip to be measured, steps S11 - S13 are sequentially executed to determine whether the current photosensitive chip to be measured is qualified. That is to say, steps S11 - S13 provided in this application can also be used as a way to determine the first preset threshold parameter. After determining the first preset threshold, it is then used to judge which chips in a batch of chips have linearity that meets the corresponding requirements, that is, to judge which chips are qualified.

[0096] In the process of executing step S13, that is, in the process of judging which chips are qualified, the following method 1 or method 2 can be adopted.

[0097]

Method 1

[0098] According to the preset order of N pictures, the following steps are sequentially executed: determine the deviation degree between the first correlation relationship and the second correlation relationship of the current picture, judge whether the current deviation degree is greater than the first preset threshold. If so, mark the current picture, and judge whether the number of marked pictures reaches M. If it reaches M, it is determined that the photosensitive chip to be measured is unqualified; if it does not reach M, continue to judge the next picture to determine whether the next picture needs to be marked until all N pictures are processed. If when judging whether the current deviation degree is greater than the first preset threshold, the current deviation degree is less than or equal to the first preset threshold, continue to judge the next picture to determine whether the next picture needs to be marked until all N pictures are processed. When the number of marked pictures after all pictures are processed is less than or equal to M, it is determined that the photosensitive chip to be measured is qualified.

[0099] For example, when N is 33 and M is 2, denoted as n1, n2... n32, n33 respectively, the pictures are processed in the current order. For example, determine the deviation degree between the first correlation relationship and the second correlation relationship of n1. If the current deviation degree is greater than the first preset threshold, mark n1. The number of marked pictures is 1 and does not reach M (i.e., 2), so continue to perform the same processing on n2.

[0100] When n2 is marked, the number of marked pictures reaches 2, and it can be determined that the photosensitive chip to be tested is unqualified.

[0101] When n2 is not marked, then the same process is continued for n3. Assuming that none of n3 - n33 are marked, then the number of marked pictures is 1, and it can be determined that the photosensitive chip to be tested is qualified.

[0102]

Method 2

[0103] For each of the N pictures, first determine the deviation degree corresponding to each picture, then determine whether the deviation degree corresponding to each picture is greater than the first preset threshold, and finally count the number of pictures among the N pictures whose deviation degrees are greater than the first preset threshold. If it is greater than M, it is determined that the photosensitive chip to be tested is unqualified; if it is less than or equal to M, it is determined that the photosensitive chip to be tested is qualified.

[0104] For example, when N is taken as 33 and M is taken as 2, denoted as n1, n2... n32, n33 respectively, determine whether the deviation degree corresponding to each picture is greater than the first preset threshold. When the deviation degrees of 2 pictures are greater than the first preset threshold, it can be determined that the photosensitive chip to be tested is unqualified; when the deviation degree of 1 picture is greater than the first preset threshold, it can be determined that the photosensitive chip to be tested is qualified.

[0105] In summary, in this embodiment, by processing the N pictures taken by the photosensitive chip to be tested, the first correlation relationship between the brightness value and the exposure time in each picture, and the second correlation relationship between the brightness value and the exposure time among the N pictures are determined. Based on the deviation degree between the first correlation relationship and the second correlation relationship, it is determined whether the brightness value and the exposure time of the photosensitive chip to be tested meet the requirements, that is, it is determined whether the photosensitive chip to be tested is qualified. Using this method to detect the photosensitive chip before it leaves the factory can improve the imaging stability of the photosensitive chip in the subsequent use process after leaving the factory, and improve the sensitivity of the photosensitive chip to brightness and exposure time.

[0106] On the basis of the above embodiment, an optimization scheme is also provided, specifically including (steps S21 - step S24):

[0107] Step S21, obtain N pictures taken by the photosensitive chip to be tested under preset conditions, and the exposure times of the N pictures are different; N is a positive integer greater than or equal to 2.

[0108] Step S22, identify the target type channels of each picture;

[0109] Step S23, determine the third correlation relationship between the brightness value and the exposure time of the target type channels of each picture respectively, and the fourth correlation relationship between the brightness values and the exposure times of the target type channels among the N pictures;

[0110] Step S24, if the deviation degree between the third correlation relationship and the fourth correlation relationship corresponding to the target type channels in at least P pictures among the N pictures is greater than the second preset threshold, it is determined that the photosensitive chip to be tested is unqualified; P is a positive integer less than or equal to N and greater than or equal to 1.

[0111] Regarding step S21, obtain N pictures taken by the photosensitive chip to be tested under preset conditions, and the exposure times of the N pictures are different; N is a positive integer greater than or equal to 2.

[0112] Step S21 is similar to step S11, and will not be elaborated here.

[0113] Regarding step S22, identify the target type channels of each picture.

[0114] Generally, a photosensitive chip has 4 types of channels, which may include R, Gr, Gb, and B (the original picture is composed of three primary colors, namely red R, green (Gr and Gb), and blue B. Among them, green accounts for 2 of the 4 types), as Figure 3 shown. The target type channel can be any one of R, Gr, Gb, and B, or a combination of any two, three, or four of R, Gr, Gb, and B. In this embodiment, only the case where "the target type channel is any one of R, Gr, Gb, and B" is taken as an example for illustration.

[0115] When the target type channel is a combination of any two or three channels, it can be considered a variation of "the target type channel is any one of R, Gr, Gb, and B", and the specific description can refer to the relevant descriptions of steps S21 - S24.

[0116] When the target type channel is a combination of these four channels of R, Gr, Gb, and B, the corresponding solution is the same as the solution provided in steps S11 - S13 above, and the specific description can refer to the relevant descriptions of steps S11 - S13.

[0117] To identify the target type channels in the picture, reference can be made to the related technology, and it will not be elaborated here.

[0118] For example, when the target type channel is the R channel, after identifying the R channel of a certain picture among the N pictures, the obtained channel picture is one - quarter of the original picture.

[0119] Regarding step S23, determine the third correlation relationship between the brightness value and the exposure time of the target type channels of each picture, and the fourth correlation relationship between the brightness values and the exposure times of the target type channels among the N pictures.

[0120] In the following embodiments, the R channel will be used as the target type channel to illustrate steps S23 and S24.

[0121] The principle of step S23 is similar to that of step S12. The difference is that step S12 is for each complete picture to determine the first association relationship of each complete picture and the second association relationship of N complete pictures. While step S23 is for the third association relationship corresponding to the R channel in each picture and the fourth association relationship of all R channels in N pictures.

[0122] Among them, the third association relationship corresponds to the first association relationship, and the fourth association relationship corresponds to the second association relationship.

[0123] Regarding step S24, if the deviation degree between the third association relationship and the fourth association relationship corresponding to the target type channel of at least P pictures among N pictures is greater than the second preset threshold, it is determined that the photosensitive chip to be tested is unqualified; P is a positive integer less than or equal to N and greater than or equal to 1.

[0124] The principle of step S24 is similar to that of step S13. The difference is that step S13 is for each complete picture to determine whether the photosensitive chip to be tested is qualified through the deviation degree corresponding to each complete picture. While step S23 is for the R channel in each picture and determines whether the photosensitive chip to be tested is qualified through the deviation degree corresponding to the R channel.

[0125] After executing step S24, the method further includes:

[0126] Step S25, if the deviation degree between the third association relationship and the fourth association relationship corresponding to the target type channel of at least N - P + 1 pictures among N pictures is less than or equal to the second preset threshold, then use another type of channel as the new target type channel, and sequentially execute steps S22 - S24. When the parameters of all types of channels in the picture all meet the condition that "the deviation degree between the third association relationship and the fourth association relationship corresponding to the target type channel of at least N - P + 1 pictures among N pictures is less than or equal to the second preset threshold", it is determined that the photosensitive chip to be tested is qualified.

[0127] In summary, the present application separately determines whether the linear relationship between the brightness value and the exposure time is satisfied for different channels in each picture, which can take into account the factor that different channels have different photosensitivity sensitivities, and thus can more accurately judge the linear relationship between the brightness value and the exposure time during the shooting process of the photosensitive chip to be tested, and can also more accurately identify whether the photosensitive chip to be tested belongs to a qualified product. When the linear relationship between the brightness value and the exposure time during the shooting of the photosensitive chip is better, the performance of the photosensitive chip during the shooting of the picture will be more stable.

[0128] For example, during the first shot, a relatively short exposure time (e.g., 4 ms) is used for shooting, and the resulting image has a relatively low brightness value (e.g., 400), making the image appear darker. During the second shot, if the desired image brightness is 800, the exposure time can be correspondingly set to 8 ms, and the resulting image brightness will be around 800. That is to say, the better the linear relationship between the brightness value and the exposure time when the photosensitive chip captures an image, the more convenient it is for the photographer to adjust the exposure time during the shooting process to make the brightness of the captured image meet the photographer's requirements.

[0129] Taking a certain model of photosensitive chip to be tested as an example, steps S21 - S25 will be described (for the purpose of differentiating from the above steps, the following will be described using the names of steps 1 - 7).

[0130] Step 1, set the environmental parameters and chip parameters.

[0131] The light source uses a uniform flat light source, the light source color temperature is set to 5100 k, and the light source brightness is set to 100000 lux. The digital gain of the photosensitive chip to be tested is set to 1 times, and the analog gain is set to 8 times.

[0132] Step 2, use the photosensitive chip to be tested to capture a target number of images under the above environmental parameters and chip parameters.

[0133] The maximum exposure time of the photosensitive chip to be tested is 33 ms. 33 images are captured, and the exposure time corresponding to each image is in sequence: 1 ms, 2 ms, 3 ms, 4 ms,..............31 ms, 32 ms, 33 ms (the adjacent exposure times differ by 1 ms).

[0134] Step 3, the channel sorting in the images captured by the photosensitive chip to be tested can be referred to Figure 3 . Identify the R channel in each image (it is also possible to first identify any one of the Gr, Gb, or B channels, here taking the R channel as an example), and form a new image that only contains the R channel.

[0135] Step 4, for each new image, take the central area that occupies one-tenth of the length and width of each new image as the target area, specifically referring to Figure 4 (ROI represents the target area, width represents the width, and height represents the height). And take the brightness value of the target area as the brightness value of each new image, which can be specifically referred to Table 1.

[0136] Step 5, according to the relationship between the brightness values and the exposure times of the 33 new images, determine the reference slope, which can specifically refer to Figure 5 and Table 1. The horizontal axis is the exposure time, and the vertical axis is the brightness value. The resulting straight line can be represented by y = 16.791x - 1.67.

[0137] Table 1

[0138]

[0139]

[0140] Step 6: Calculate the deviation degree of each new picture according to the slope of each new picture and the reference slope, and specifically refer to Table 1 for details.

[0141] Step 7 includes the following two situations:

[0142]

Situation 1

[0143] Assume that when the deviation degrees of the pictures taken by the photosensitive chip to be tested are all less than the preset threshold, it is considered that the photosensitive chip to be tested is qualified (that is, assume that P in Steps S24 and S25 takes 1). Then, in this example, when the preset threshold is set to 3%, it can be seen from Table 1 that the deviation degree corresponding to the picture with an exposure time of 2 ms is greater than 3%. Then it can be determined that the photosensitive chip to be tested is unqualified. In this case, it is no longer necessary to identify and judge the Gr, Gb, or B channel.

[0144]

Situation 2

[0145] Assume that when there is 1 or 0 deviation degree less than the preset threshold in the pictures taken by the photosensitive chip to be tested, it is considered that the photosensitive chip to be tested is qualified (that is, assume that P in Steps S24 and S25 takes 2). Then, in this example, when the preset threshold is set to 3%, it can be seen from Table 1 that the deviation degree corresponding to the picture with an exposure time of 2 ms is greater than 3%. It can be determined that the R channel meets the requirements. However, at this time, it cannot be determined that the photosensitive chip to be tested is qualified. It is still necessary to separately execute Steps 3 - 7 for the Gr, Gb, and B channels for identification and judgment. When the deviation degrees in the new pictures corresponding to the Gr, Gb, and B channels are all less than the preset threshold, it is considered that the photosensitive chip to be tested is qualified; otherwise, it is considered that the photosensitive chip to be tested is unqualified.

[0146] In summary, in this embodiment, by analyzing the relationship between the brightness value corresponding to each channel in the N pictures taken by the photosensitive chip to be tested and the exposure time, as well as the relationship between the brightness values and exposure times among the N pictures, the linear degree between the brightness value and the exposure time when the photosensitive chip to be tested is working is determined, and then whether the photosensitive chip to be tested is qualified is determined. The qualified photosensitive chips screened in this way have better linearity, and can better meet the needs of the photographer for brightness and exposure time during subsequent shooting. On the one hand, the quality of the taken pictures is improved, and on the other hand, the user experience of the photographer is also enhanced.

[0147] In addition, in this embodiment, for each channel in the N pictures taken by the photosensitive chip to be tested, the linear degree between the brightness value and the exposure time of the photosensitive chip to be tested during operation is determined. If a certain photosensitive chip to be tested is detected as unqualified, the cause of the unqualified photosensitive chip can be roughly determined, and then the production line or production process of the corresponding chip can be adjusted to reduce the number of unqualified chips in the subsequent process and improve the yield rate of the corresponding production line.

[0148] Based on the same inventive concept, the present application provides a photosensitive chip detection device as shown in Figure 6 The device includes:

[0149] A picture acquisition module 61, configured to acquire N pictures obtained by photographing a photosensitive chip to be tested under preset conditions, where the exposure times of the N pictures are different; N is a positive integer greater than or equal to 2;

[0150] A relationship determination module 62, configured to determine a first association relationship between the brightness value and the exposure time of each picture, and a second association relationship between the brightness values and the exposure times among the N pictures;

[0151] A judgment module 63, configured to determine that the photosensitive chip to be tested is unqualified if the deviation degree between the first association relationship and the second association relationship corresponding to at least M pictures among the N pictures is greater than a first preset threshold; M is a positive integer less than or equal to N and greater than or equal to 1.

[0152] Further, the device further includes:

[0153] An exposure time determination module, configured to determine the exposure time corresponding to each of the N pictures when the photosensitive chip to be tested takes the N pictures according to the maximum exposure time of the photosensitive chip to be tested during the process of the photosensitive chip to be tested taking the N pictures or before taking the N pictures.

[0154] Further, the device further includes:

[0155] A brightness value determination module, configured to delimit a target area in each picture according to the detection requirements of the photosensitive chip to be tested before determining the first association relationship between the brightness value and the exposure time of each picture; and determine the brightness value of each picture according to the brightness value of the target area of each picture.

[0156] Further, the target area of each picture is the central area.

[0157] Further, the relationship determination module 62 includes:

[0158] A first association relationship determination sub-module, configured to determine a first association relationship between the brightness value and the exposure time in each picture according to the brightness value and the exposure time of each picture and the dark current value of the photosensitive chip to be tested, and the first association relationship is related to the linear relationship.

[0159] Further, the relationship determination module 62 includes:

[0160] A second correlation relationship determination sub-module, configured to fit the brightness values and exposure times among N pictures, and determine a second correlation relationship between the brightness values and exposure times among the N pictures, where the second correlation relationship is related to a linear relationship.

[0161] Further, the apparatus further includes:

[0162] A channel identification module, configured to identify the target type channels of each picture after obtaining N pictures;

[0163] A relationship determination module 62, configured to determine a third correlation relationship between the brightness value and exposure time of the target type channels of each picture, and a fourth correlation relationship between the brightness values and exposure times of the target type channels among the N pictures;

[0164] A judgment module 63, configured to determine that the photosensitive chip to be tested is unqualified if the deviation degree between the third correlation relationship and the fourth correlation relationship corresponding to the target type channels of at least P pictures among the N pictures is greater than a second preset threshold; P is a positive integer less than or equal to N and greater than or equal to 1.

[0165] Based on the same inventive concept, the present application further provides an electronic device as shown in Figure 7 and includes:

[0166] A processor 71;

[0167] A memory 72 for storing executable instructions of the processor 71;

[0168] Wherein, the processor 71 is configured to execute to implement a photosensitive chip detection method as provided above.

[0169] Based on the same inventive concept, the present application further provides a non-transitory computer-readable storage medium. When the instructions in the storage medium are executed by the processor 71 of the electronic device, the electronic device can be enabled to execute and implement a photosensitive chip detection method as provided above.

[0170] Since the electronic device introduced in this embodiment is the electronic device adopted for implementing the information processing method in the embodiments of the present application, based on the information processing method introduced in the embodiments of the present application, those skilled in the art can understand the specific implementation manners and various variations of the electronic device in this embodiment. Therefore, the implementation of how the electronic device implements the method in the embodiments of the present application will not be described in detail here. As long as the electronic device adopted by those skilled in the art to implement the information processing method in the embodiments of the present application belongs to the scope protected by the present application.

[0171] Those skilled in the art will appreciate that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0172] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and combinations of flows and / or blocks in the flowcharts and / or block diagrams, can be realized by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices produce means for realizing the functions specified in one Figure 1 flow or multiple flows and / or blocks Figure 1 or multiple blocks.

[0173] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory produce a manufactured article including instruction means that realizes the functions specified in one Figure 1 flow or multiple flows and / or blocks Figure 1 or multiple blocks.

[0174] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for realizing the functions specified in one Figure 1 flow or multiple flows and / or blocks Figure 1 or multiple blocks.

[0175] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications once they know the basic creative concepts. Therefore, the appended claims are intended to be construed to include the preferred embodiments as well as all changes and modifications falling within the scope of the present invention.

[0176] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims

1. A method for detecting a photosensitive chip, characterized in that, The method includes: Obtaining N pictures taken by the photosensitive chip to be tested under preset conditions, where the exposure times of the N pictures are different; N is a positive integer greater than or equal to 2; Determining the first correlation relationship between the brightness value and the exposure time of each picture, and the second correlation relationship between the brightness values and the exposure times among the N pictures; If the deviation degree between the first correlation relationship and the second correlation relationship corresponding to at least M pictures among the N pictures is greater than a first preset threshold, determining that the photosensitive chip to be tested is unqualified; M is a positive integer less than or equal to N and greater than or equal to 1.

2. The method according to claim 1, wherein During the process of the photosensitive chip to be tested taking the N pictures or before taking the N pictures, the method further includes: Determining the exposure time corresponding to each of the N pictures when the photosensitive chip to be tested takes the N pictures according to the maximum exposure time of the photosensitive chip to be tested.

3. The method according to claim 1, wherein Before determining the first correlation relationship between the brightness value and the exposure time of each picture, the method further includes: Defining a target area in each picture according to the detection requirements of the photosensitive chip to be tested; Determining the brightness value of each picture according to the brightness value of the target area of each picture.

4. The method according to claim 3, wherein The target area of each picture is the central area.

5. The method according to claim 1, characterized in that The determining the first correlation relationship between the brightness value and the exposure time of each picture includes: Determining the first correlation relationship between the brightness value and the exposure time in each picture according to the brightness value and the exposure time of each picture, and the dark current value of the photosensitive chip to be tested, where the first correlation relationship is related to a linear relationship.

6. The method according to claim 1, characterized in that, The determining the second correlation relationship between the brightness values and the exposure times among the N pictures includes: Fitting the brightness values and the exposure times among the N pictures to determine the second correlation relationship between the brightness values and the exposure times among the N pictures, where the second correlation relationship is related to a linear relationship.

7. The method according to claim 1, characterized in that, After obtaining the N pictures, the method further includes: Identifying the target type channels of each picture; Determining the third correlation relationship between the brightness value and the exposure time of the target type channels of each picture, and the fourth correlation relationship between the brightness values and the exposure times of the target type channels among the N pictures; If the deviation degree between the third correlation relationship and the fourth correlation relationship corresponding to the target type channels of at least P pictures among the N pictures is greater than a second preset threshold, determining that the photosensitive chip to be tested is unqualified; P is a positive integer less than or equal to N and greater than or equal to 1.

8. A photosensitive chip detection device, characterized in that, The device includes: A picture acquisition module, configured to obtain N pictures taken by the photosensitive chip to be tested under preset conditions, where the exposure times of the N pictures are different; N is a positive integer greater than or equal to 2; A relationship determination module, configured to determine the first correlation relationship between the brightness value and the exposure time of each picture, and the second correlation relationship between the brightness values and the exposure times among the N pictures; A judgment module, configured to determine that the photosensitive chip to be tested is unqualified if the deviation degree between the first correlation relationship and the second correlation relationship corresponding to at least M pictures among the N pictures is greater than a first preset threshold; M is a positive integer less than or equal to N and greater than or equal to 1.

9. An electronic device, characterized in that, Includes: A processor; A memory for storing the processor-executable instructions; Wherein, the processor is configured to execute to implement a photosensitive chip detection method according to any one of claims 1 to 7.

10. A non-transitory computer-readable storage medium, when the instructions in the storage medium are executed by a processor of an electronic device, enabling the electronic device to execute and implement a photosensitive chip detection method according to any one of claims 1 to 7.

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