Assembly, method, device and system for measuring exposure time of image sensor

Abstract

The invention discloses an image sensor exposure time measuring assembly, method, device and system, and the measuring assembly comprises a target plate which is annular and is provided with a square test block; the two rotating shafts are used for tensioning the target plate; and the driving structure is used for driving the rotating shaft to rotate so as to drive the target plate to rotate. The whole system does not need a light source and a control circuit is simple.

Description

Technical Field

[0001] The present invention belongs to the technical field of exposure time measurement, and in particular relates to an image sensor exposure time measurement component, method, device and system. Background Art

[0002] Image sensors are a type of device used for imaging that can detect the spatial distribution of light intensity. Image sensors work based on the photoelectric effect. Photons enter the sensor through the lens and are absorbed by the photodiode in the sensor, generating photoelectrons. These electrons are collected and converted into electrical signals, which are amplified and processed to form a digital image.

[0003] Exposure time refers to the length of time that each pixel on the image sensor accumulates photoelectrons. During this time, the photodiode of the image sensor collects incident photons and converts them into photoelectrons. As a detailed parameter in photography, exposure time affects the signal-to-noise ratio, dynamic range, and motion blur of the image. The choice of exposure time is different in different environments. For example, when the lighting conditions are poor or the pixel area of ​​the image sensor is small, the exposure time should be appropriately increased. When the imaging area is overexposed or the relative motion speed of the imaging object and the lens is fast, the exposure time should be appropriately reduced.

[0004] Image sensors are used in various cameras, camcorders and cameras. During research and development, production and acceptance, it is usually necessary to test whether the exposure time pre-set in the system is accurate. If the exposure time accuracy is not high, it will affect the user's precise setting and control of photographic parameters, which is especially critical in imaging scenarios where high exposure time accuracy is required.

[0005] The existing image sensor exposure time measurement method uses controllable LED light array and scanning light method. The controllable LED light array is taken as an example of "A camera / camcorder exposure time test system and method" with application number "201510944019.6", and the scanning light method is taken as an example of "Imaging equipment exposure time test device" with application number "201810866093.4". However, existing methods for measuring the exposure time of image sensors require a light source and complex circuit control. Summary of the invention

[0006] In order to solve the problem that the existing method requires a light source and has complex circuit control, the present invention provides an image sensor exposure time measurement component, method, device and system, which do not require a light source and have a simple control circuit.

[0007] The purpose of the present invention is achieved through the following technical solutions: A first aspect of the present invention provides an image sensor exposure time measurement component, comprising: a target plate, the target plate is ring-shaped, and a square test block is arranged on the target plate; Two rotating shafts, the two rotating shafts are used to tension the target plate; A driving structure is used to drive the rotating shaft to rotate so as to drive the target plate to rotate.

[0008] A second aspect of the present invention provides a method for measuring exposure time of an image sensor, comprising the following steps: Obtaining image information containing at least one complete test block in an image sensor exposure time measurement component described in the first aspect and any possible design thereof taken by the image sensor to be tested; Calculating the moving speed of the test block according to the output speed of the driving structure and the diameter of the rotating shaft; Calculate the length of the trail of the test block in the image relative to the test block on the target plate along the moving direction thereof according to the complete test block image information; The exposure duration is calculated according to the smear length, the length of the test block on the target plate along its moving direction, the moving speed of the test block and the length of the test block in the image along its moving direction.

[0009] The third aspect of the present invention provides an image sensor exposure time measuring device, comprising a memory and a controller which are communicatively connected in sequence, wherein the memory stores a computer program, and the controller is used to read the computer program and execute an image sensor exposure time measuring method described in the second aspect and any possible design thereof.

[0010] A fourth aspect of the present invention provides an image sensor exposure time measurement system, comprising: An image sensor exposure time measuring component as described in the first aspect and any possible design thereof, An image sensor exposure time measuring device as described in the third aspect and any possible design thereof.

[0011] Compared with the prior art, the present invention has at least the following advantages and beneficial effects: The present invention does not require a light source, and the circuit control only needs to control the rotation of the driving structure, and the control circuit is simple and easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0013] Figure 1 It is a structural schematic diagram of the exposure time measuring component of the image sensor of the present invention; Figure 2 An exploded view of an exposure time measuring component of an image sensor of the present invention; Figure 3 Schematic diagram of the test block in the image. DETAILED DESCRIPTION

[0014] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0015] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0016] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0017] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0018] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the invention is usually placed when in use, or the positions or positional relationships commonly understood by those skilled in the art, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0019] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0020] A first aspect of the present invention provides an image sensor exposure time measurement component, such as Figure 1 As shown, it includes a target plate 1, two rotating shafts 2 and a driving structure 3, wherein the target plate 1 is ring-shaped, and a square test block 11 is arranged on the target plate, and the color of the test block is different from the color of the non-test block area on the target plate; the two rotating shafts 2 are used to tension the target plate 1; the driving structure 3 is used to drive the rotating shaft to rotate to drive the target plate to rotate, and when the target plate rotates, the moving direction of the test block is its length direction.

[0021] By adopting the above-mentioned component structure, the two rotating shafts tension the annular target plate to rotate, forming a structure similar to a conveyor belt. The driving structure drives the rotating shaft to rotate and drives the test block on the target plate to move at the same time.

[0022] The test block is square, and may be a rectangle or a square. Preferably, in order to simplify the calculation process in the method, the test block is square.

[0023] The color of the test block is different from the color of the non-test block area. In order to improve the test accuracy, the contrast ratio between the color of the test block and the color of the non-test block area is ≥ 95%. Preferably, the test block is set to black and the non-test block area is set to white.

[0024] There can be one or more test blocks. When only one test block is provided, the probability of the image sensor capturing the test block at one time during the test is small. Therefore, in order to improve the test efficiency, the test block has at least two rows and / or at least two columns.

[0025] For example, Figure 1 As shown, the target board is provided with 18 columns and 4 rows of test blocks.

[0026] When multiple rows and columns are set, the distance between two adjacent rows of test blocks is preferably such that no overlap occurs between two adjacent test blocks in the same row when the image sensor is photographing.

[0027] In order to improve the test accuracy, the length of the test block should ensure that the deviation of the pixel width in repeated measurements is no more than ±2% of the average value. If the error is too large, the spatial size of the square should be increased.

[0028] In order to improve the stability of the target plate rotation and improve the test accuracy, the assembly also includes a bracket, which includes a bottom plate 41, a support crossbar 42, and a support vertical rod 43 connected between the support crossbar 42 and the bottom plate 41, and the two ends of the rotating shaft are rotatably connected to the bottom plate and the support crossbar. Specifically, the two ends of the support vertical rod 43 can be connected to the support crossbar 42 and the bottom plate 41 through bearings.

[0029] The second aspect of the present invention provides an image sensor exposure time measurement method, which can be but is not limited to being executed by an image sensor exposure time measurement device or implemented by manual operation. The image sensor exposure time measurement device can be software, or a combination of software and hardware. The image sensor exposure time measurement device can be integrated in smart mobile terminals, tablets, computers and other smart devices. Specifically, the image sensor exposure time measurement method includes the following steps S01 to S04. It should be noted that the step identification in this scheme is only for the convenience of explaining the method and does not constitute a limitation on the order of sequence. The order of each step is based on its language description and the order of each signal.

[0030] Step S01: obtaining image information containing at least one complete test block in an image sensor exposure time measurement component as described in any one of the first aspects, which is taken by an image sensor to be tested.

[0031] The driving structure drives the rotating shaft to rotate and drives the target plate to rotate at a uniform speed. At the same time, the image sensor to be tested captures an image of the target plate, wherein the image needs to contain the test block.

[0032] Step S02: Calculate the moving speed of the test block according to the output rotation speed of the driving structure and the diameter of the rotating shaft.

[0033] Assuming the output speed of the drive structure is n, the shaft diameter is R, and the transmission ratio is 1:1, the moving speed V of the test block is: V=π*R*n.

[0034] Step S03, calculating the length of the trailing image of the test block in the image relative to the test block on the target plate along the moving direction thereof according to the complete test block image information.

[0035] Specifically, assuming that the length of the test block is A and the width is B, the pixel length of the test block in the image along its moving direction is b, and the pixel width of the test block in the image perpendicular to the moving direction is a. Then, without considering the exposure time, the length of the test block in a normal image should be: (A / B)*a.

[0036] Then the length of the trailing image is: b-(A / B)*a.

[0037] When the test block is a square, its length and width are equal. The length of the smear is ba.

[0038] That is, when the test block is a square, the original square test block in the image becomes a rectangle, such as Figure 3 When the test block is rectangular, its length becomes longer relative to its width.

[0039] Step S04, calculating the exposure time according to the smear length, the length of the test block on the target plate along its moving direction, the moving speed of the test block and the length of the test block in the image along its moving direction.

[0040] After exposure, the test block in the image, which originally had a length of (A / B)*a and a width of a, becomes a test block with a length of b and a width. The length of the smear is caused by the continuous movement of the target plate within the integration time t. In this regard, the integration time t is: t=A*(b-(A / B)*a) / (a*V), That is, t= A*(b-(A / B)*a) / ( a*π*R*n).

[0041] When the test block is a square, The exposure time can be simplified to: .

[0042] The exposure time obtained by the above method can be used by imaging chip and camera manufacturers to verify the performance of imaging products during the research and development, production and acceptance process. The whole process does not require a light source, the control circuit is simple, and only the motor needs to be driven to rotate.

[0043] The third aspect of the present invention provides an image sensor exposure time measurement device, including a memory and a controller that are sequentially connected in communication, the memory stores a computer program, and the controller is used to read the computer program and execute an image sensor exposure time measurement method described in the second aspect and any possible one thereof. For example, the memory may include, but is not limited to, a random access memory (RAM), a read-only memory (ROM), a flash memory (Flash Memory), a first-in-first-out memory (FIFO) and / or a first-in-last-out memory (FILO), etc.; the controller may not be limited to a microcontroller of the STM32F105 series. In addition, the computer device may also include, but is not limited to, a power supply unit, a display screen and other necessary components.

[0044] A fourth aspect of the present invention provides an image sensor exposure time measurement system, comprising: An image sensor exposure time measuring component as described in the first aspect and any possible design thereof, An image sensor exposure time measuring device as described in the third aspect and any possible design thereof.

[0045] The method for using the system in conjunction with the image sensor to be tested is described in detail in the second aspect, so it will not be repeated here.

[0046] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An image sensor exposure time measurement component, characterized in that: include: a target plate, the target plate being ring-shaped, and having a square test block disposed thereon, the color of the test block being different from the color of a non-test block area on the target plate; Two rotating shafts, the two rotating shafts are used to tension the target plate; The driving structure is used to drive the rotating shaft to rotate so as to drive the target plate to rotate; and when the target plate rotates, the moving direction of the test block is the length direction thereof.

2. The image sensor exposure time measuring component according to claim 1, characterized in that: The test block is square.

3. The image sensor exposure time measuring component according to claim 1, characterized in that: The test block has at least two rows and / or the test block has at least two columns.

4. The image sensor exposure time measuring component according to claim 1, characterized in that: It also includes a bracket, which includes a bottom plate, a supporting crossbar, and a supporting vertical rod connected between the supporting crossbar and the bottom plate. Both ends of the rotating shaft are rotatably connected to the bottom plate and the supporting crossbar respectively.

5. A method for measuring exposure time of an image sensor, characterized in that: The following steps are involved: Acquire image information containing at least one complete test block in an image sensor exposure time measurement component as described in any one of claims 1 to 4 taken by the image sensor to be tested; Calculating the moving speed of the test block according to the output speed of the driving structure and the diameter of the rotating shaft; Calculate the length of the trail of the test block in the image relative to the test block on the target plate along the moving direction thereof according to the complete test block image information; The exposure time is calculated according to the smear length, the length of the test block on the target plate along its moving direction, the moving speed of the test block and the length of the test block in the image along its moving direction.

6. The method for measuring exposure time of an image sensor according to claim 5, characterized in that: The test block is square. The length of the smear of the test block in the image relative to the test block on the target plate along the moving direction is calculated based on the complete test block image information as ba, where a is the pixel length of the test block in the image along the moving direction, and b is the pixel width of the test block in the image perpendicular to the moving direction.

7. The method for measuring exposure time of an image sensor according to claim 6, characterized in that: The exposure time t is calculated according to the smear length, the length of the test block on the target plate along its moving direction, the moving speed of the test block and the length of the test block in the image along its moving direction: , where A is the length of the test block on the target plate along its moving direction, and V is the moving speed of the test block.

8. An image sensor exposure time measuring device, comprising a memory and a controller which are sequentially connected in communication, wherein a computer program is stored in the memory, characterized in that: The controller is used to read the computer program and execute the method for measuring exposure time of an image sensor according to any one of claims 5 to 7.

9. An image sensor exposure time measurement system, characterized in that: include: An image sensor exposure time measuring component as claimed in any one of claims 1 to 4, An image sensor exposure time measuring device as claimed in claim 8.

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