Camera SFR testing device with focal length adjustable function

Abstract

The invention discloses a camera SFR testing device with a focal length adjustable function, and particularly relates to the technical field of camera SFR testing, which comprises a machine body, an image analyzer used for analyzing an image acquired by a camera and performing SFR testing, a mounting seat used for mounting the camera, and a measurement pattern generator used for providing a measurement pattern, a central processing unit is arranged on one side of the image analyzer, a position adjusting structure and a clamping stabilizing mechanism are arranged on the inner side of the machine body, and the clamping stabilizing mechanism is used for clamping and fixing a camera lens so as to prevent the camera lens from vibrating; the system further comprises a lens position capturing module, a vibration amplitude acquisition module and a vibration frequency acquisition module. The problem that the telescopic camera is out of focus due to lens vibration in the focal length adjusting process is solved, and the image definition and the SFR test accuracy are ensured through real-time vibration monitoring and intelligent adjustment.

Description

Technical Field

[0001] The present invention relates to the technical field of camera SFR testing, and more specifically, to a camera SFR testing device with a focus adjustable function. Background Art

[0002] The SFR test device for cameras with adjustable focal length is a special device that integrates focal length adjustment and image quality testing functions. Its main function is to test and evaluate the imaging quality of cameras at different focal lengths, especially through the spatial frequency response (SFR) test, to measure the clarity, sharpness and image detail restoration ability of cameras under different focal length conditions. Specifically, the device can automatically or manually adjust the focal length of the camera, and perform imaging tests at multiple focal length positions to analyze the impact of focal length changes on image quality. As a key image quality evaluation method, the SFR test can accurately evaluate the resolution and detail presentation capabilities of the camera at different focal lengths. This device is of great significance in camera research and development, production, quality control and image performance evaluation. It not only helps to detect and verify the imaging effect of the camera, but also optimizes the focal length adjustment mechanism and improves the overall image quality of the camera. It is widely used in security monitoring, autonomous driving, industrial inspection and other fields.

[0003] Existing SFR test devices for cameras with adjustable focus function evaluate the image quality of the camera at different focal lengths through a series of precise steps. First, the device automatically or manually adjusts the focus of the camera, usually through an electric motor or mechanical control system to ensure that the focus changes within a predetermined range. Next, the device aims the camera at a standard test pattern, usually a high-contrast resolution test card or a sine wave pattern, which can simulate image details at different spatial frequencies. Then, the device gradually shoots the test pattern at different focal lengths and measures the spatial frequency response (SFR) of the image through image analysis software, that is, testing the clarity, sharpness and resolution of the camera at each focal length. Finally, the system generates a series of SFR data to analyze the impact of focal length changes on the camera's imaging quality and evaluate its performance at different focal lengths. This process ensures that the image quality of the camera under various focal length conditions meets the expected standards and helps developers or manufacturers optimize the focus adjustment system and image quality.

[0004] The prior art has the following deficiencies: when adjusting the focal length, especially when the focal length changes greatly (for example, from telephoto to wide angle), the optical components inside the telescopic camera lens need to be displaced to a large extent. Since the lens of the telescopic camera moves outward or inward during the focal length adjustment process, if the lens after the focal length adjustment lacks sufficient support and stability, it may vibrate slightly, resulting in defocus at the moment of image capture. This situation is particularly obvious when the focal length adjustment range is large. However, the existing camera SFR test device with adjustable focal length function cannot effectively stabilize the position of the telescopic camera lens after the focal length adjustment, so it is impossible to avoid the vibration of the lens after the focal length adjustment, resulting in defocus of the image during shooting, which in turn makes the test image blurred. This will directly affect the accuracy of the SFR test, resulting in a low SFR calculation result, making the test data unreliable.

[0005] The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not constitute the prior art that is already known to one of ordinary skill in the art. Summary of the invention

[0006] In order to overcome the above defects of the prior art, the present invention provides a camera SFR testing device with an adjustable focus function to solve the problems raised in the above background technology.

[0007] To achieve the above object, the present invention provides the following technical solutions: A camera SFR test device with an adjustable focal length function comprises a body, an image analyzer for analyzing and performing SFR testing on images collected by a camera, a mounting base for mounting the camera, and a measurement pattern generator for providing a measurement pattern, wherein a central processing unit is disposed on one side of the image analyzer, and a position adjustment structure and a clamping and stabilizing mechanism are disposed on the inner side of the body, wherein the clamping and stabilizing mechanism is used to clamp and fix a camera lens to prevent the camera lens from vibrating, and the position adjustment mechanism is used to control the clamping and stabilizing mechanism to accurately move to a position for clamping and fixing the camera lens; Also includes: A lens position capture module is arranged on the inner bottom wall of the body, and is used to obtain the position information of the camera lens in real time, and transmit it to the central processor for analysis to determine the position of the camera lens; The vibration amplitude acquisition module is arranged on the inner bottom wall of the body, and is used to obtain the vibration amplitude of the camera lens at different times within a period of time in real time, and generate the vibration amplitude variation coefficient through the central processing unit; The vibration frequency acquisition module is arranged on the inner wall of the mounting base, and is used to obtain the vibration frequency of the camera at different times within a period of time in real time, and generate a vibration frequency deviation index through the central processing unit; The central processing unit performs a comprehensive analysis on the generated vibration amplitude variation coefficient and vibration frequency deviation index to generate a vibration judgment coefficient, which is then compared with a preset vibration judgment coefficient reference threshold. The comparison result is used to determine whether the vibration of the camera lens will affect the SFR test, and the working status of the position adjustment structure, clamping stabilization mechanism and lens position capture module is controlled based on the comparison result.

[0008] Preferably, the position adjustment mechanism includes a motor mounting frame, a motor, a gear transmission box, a screw and a sliding frame, one side of the motor mounting frame is fixedly connected to the inner wall of the machine body, the top of the motor mounting frame is fixedly connected to the bottom of the motor, the output shaft of the motor is transmission connected to the input shaft of the gear transmission box, the output shaft of the gear transmission box is transmission connected to one end of the screw, and the outer wall of the screw is transmission connected to the inner wall of the sliding frame.

[0009] Preferably, the clamping stabilization mechanism includes a cylinder mounting frame, a cylinder, a telescopic rod, an arc-shaped sponge plate and an arc-shaped sponge board, one side of the cylinder mounting frame is fixedly connected to one side of the sliding frame, the top of the cylinder mounting frame is fixedly connected to the bottom of the cylinder, the output end of the cylinder is transmission-connected to one end of the telescopic rod, the other end of the telescopic rod is fixedly connected to one side of the arc-shaped sponge plate, and the inner side wall of the arc-shaped sponge plate is fixedly connected to the outer wall of the arc-shaped sponge board.

[0010] Preferably, the output end of the central processing unit is electrically connected to the input end of the motor, the input end of the cylinder, the input end of the image analyzer and the input end of the measurement pattern generator, and the output end and input end of the lens position capture module, the output end and input end of the vibration amplitude acquisition module and the output end and input end of the vibration frequency acquisition module are electrically connected to the input end and output end of the central processing unit, respectively.

[0011] Preferably, the acquisition logic of the vibration amplitude variation coefficient is: S1. The vibration amplitude acquisition module is used to obtain the vibration amplitude of the camera lens at different times within a period of time in real time, and calibrated as , Indicates that the camera lens is within a period of time The vibration amplitude at the moment, , is a positive integer; S2. Obtain the preset maximum vibration amplitude of the camera lens allowed by the central processor and calibrate it as ; S3. The vibration amplitude of the camera lens at different times within a period of time Create a collection and add the vibration amplitudes in the collection that are greater than the preset maximum The vibration amplitude is recalibrated as , Indicates that the vibration amplitude in the set is greater than the preset maximum The vibration amplitude number, , is a positive integer; S4. Calculate the vibration amplitude variation coefficient. The calculation expression is: In the formula, is the coefficient of variation of vibration amplitude.

[0012] Preferably, the logic for obtaining the vibration frequency deviation index is: S1. The vibration frequency acquisition module is used to obtain the vibration frequency of the camera at different times within a period of time in real time and calibrate it as , Indicates that the camera is within a period of time The vibration frequency of the moment, , is a positive integer; S2. Obtain the preset maximum vibration frequency of the camera allowed by the central processor and calibrate it as ; S3. Calculate the vibration frequency deviation index. The calculation expression is: In the formula, is the vibration frequency deviation index.

[0013] Preferably, the vibration determination coefficient is expressed as: Formula analysis is performed through the central processing unit according to the formula: In the formula, is the vibration determination coefficient, and are the vibration amplitude variation coefficients and vibration frequency deviation index The preset scaling factor of and Both are greater than 0.

[0014] Preferably, the preset vibration judgment coefficient reference threshold is set to , the vibration judgment coefficient calculated by the central processor and the preset vibration judgment coefficient reference threshold Perform a comparison, and determine whether the vibration of the camera lens will affect the SFR test based on the comparison results. Control the working status of the position adjustment structure, the clamping stabilization mechanism, and the lens position capture module based on the comparison results. The specific judgment is as follows: when When the camera lens is in the state of being ... when When the camera lens is in the state of being moved, the vibration of the camera lens will affect the SFR test and generate an abnormal signal. After receiving the abnormal signal, the central processing unit generates a capture signal, a movement signal and a clamping signal, and transmits the capture signal to the lens position capture module. After receiving the capture signal, the lens position capture module performs the lens position capture work, transmits the movement signal to the motor, and after receiving the movement signal, the motor controls the position adjustment structure to perform the position adjustment work, and transmits the clamping signal to the cylinder. After receiving the clamping signal, the cylinder controls the clamping stabilization mechanism to perform the clamping stabilization work.

[0015] Technical effects and advantages of the present invention: 1. The present invention effectively solves the vibration problem caused by the telescopic camera lens during a large-scale focal length adjustment during the focal length adjustment process. The vibration of the camera lens is monitored in real time by the vibration amplitude acquisition module and the vibration frequency acquisition module. The central processing unit can determine whether the vibration of the lens will affect the SFR test results based on the calculated vibration amplitude variation coefficient and vibration frequency deviation index. If the vibration exceeds the preset tolerance threshold, the system will automatically start the position adjustment mechanism and the clamping stabilization mechanism to ensure the stability of the lens and avoid defocusing. Through this precise vibration monitoring and adjustment mechanism, the technical solution effectively ensures the stability of the camera under different focal length conditions, ensures the clarity of the image, and avoids defocusing caused by vibration.

[0016] 2. The greatest advantage of the present invention lies in its real-time feedback and dynamic adjustment capabilities. Through comprehensive analysis of vibration amplitude and frequency, the central processing unit can grasp the vibration of the lens in real time and determine the impact of vibration on the test results. When the vibration reaches a certain threshold, the system can timely adjust the position adjustment structure and the clamping stabilization mechanism to ensure the stability of the lens and avoid the impact of vibration on the focal length adjustment. In addition, the real-time monitoring function of the lens position capture module enables the system to respond quickly and accurately adjust the position of the lens, further improving the accuracy of focal length adjustment and image quality.

[0017] 3. The present invention can significantly improve the accuracy of SFR testing. The impact of vibration on SFR test results is usually difficult to avoid, especially when the focus adjustment range is large. This solution effectively avoids the defocus problem caused by lens vibration through precise vibration monitoring and lens stabilization control, thereby ensuring image quality and the accuracy of SFR calculation. The real-time analysis and intelligent control of vibration data by the central processor not only improves the stability of the equipment, but also improves the reliability of the test data, making the entire SFR test process more accurate and effective. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to facilitate understanding by those skilled in the art, the present invention is further described below in conjunction with the accompanying drawings; Figure 1 A schematic diagram of the three-dimensional structure of a camera SFR testing device with adjustable focus proposed by the present invention; Figure 2 This is a front structural schematic diagram of a camera SFR testing device with adjustable focus function proposed by the present invention; Figure 3 A schematic diagram of the top structure of a camera SFR testing device with adjustable focus proposed by the present invention; Figure 4 A schematic diagram of the installation structure of a measurement pattern generator of a camera SFR test device with adjustable focus proposed by the present invention; Figure 5 This is a schematic diagram of the structure of a position adjustment mechanism of a camera SFR testing device with adjustable focus proposed by the present invention; Figure 6 This is a schematic diagram of the structure of a clamping stabilization mechanism of a camera SFR testing device with adjustable focus proposed by the present invention; Figure 7 This is a schematic diagram of the installation structure of a vibration frequency acquisition module of a camera SFR test device with adjustable focus proposed by the present invention; Figure 8 This is a module schematic diagram of a camera SFR testing device with adjustable focus proposed by the present invention.

[0019] In the figure: 1. body; 2. image analyzer; 3. mounting base; 4. measurement pattern generator; 5. central processing unit; 6. position adjustment mechanism; 601. motor mounting frame; 602. motor; 603. gear transmission box; 604. lead screw; 605. sliding frame; 7. clamping stabilization mechanism; 701. cylinder mounting frame; 702. cylinder; 703. telescopic rod; 704. arc splint; 705. arc sponge board; 8. lens position capture module; 9. vibration amplitude acquisition module; 10. vibration frequency acquisition module. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. 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.

[0021] Example like Figure 1-8 As shown, a camera SFR test device with a focal length adjustable function includes a body 1, an image analyzer 2 for analyzing and SFR testing an image collected by a camera, a mounting base 3 for mounting the camera, and a measurement pattern generator 4 for providing a measurement pattern. A central processing unit 5 is disposed on one side of the image analyzer 2. A position adjustment structure 6 and a clamping stabilization mechanism 7 are disposed on the inner side of the body 1. The clamping stabilization mechanism 7 is used to clamp and fix the camera lens to prevent the camera lens from vibrating. The position adjustment mechanism 6 is used to control the clamping stabilization mechanism 7 to accurately move to a position for clamping and fixing the camera lens. Also includes: The lens position capturing module 8 is arranged on the inner bottom wall of the body 1, and is used to obtain the position information of the camera lens in real time, and transmit it to the central processor 5 for analysis to determine the position of the camera lens; It should be noted that the lens position capture module 8 may be an optical position sensor or other device capable of acquiring the position information of the camera lens in real time. The lens position capture module 8 is not specifically limited here and may be selected according to actual needs.

[0022] The vibration amplitude acquisition module 9 is arranged on the inner bottom wall of the body 1, and is used to obtain the vibration amplitude of the camera lens at different times within a period of time in real time, and generate the vibration amplitude variation coefficient through the central processor 5; It should be noted that the vibration amplitude acquisition module 9 can be an acceleration sensor, a displacement sensor or other equipment that can obtain the vibration amplitude of the camera lens at different times within a period of time in real time. The vibration amplitude acquisition module 9 is not specifically limited here and can be selected according to actual needs.

[0023] The vibration frequency acquisition module 10 is arranged on the inner side wall of the mounting seat 3, and is used to obtain the vibration frequency of the camera at different times within a period of time in real time, and generate a vibration frequency deviation index through the central processor 5; It should be noted that the vibration frequency acquisition module 10 can be a vibration sensor or other equipment that can obtain the vibration frequency of the camera at different times within a period of time in real time. The vibration frequency acquisition module 10 is not specifically limited here and can be selected according to actual needs.

[0024] The central processing unit 5 performs a comprehensive analysis on the generated vibration amplitude variation coefficient and vibration frequency deviation index to generate a vibration judgment coefficient, which is then compared with a preset vibration judgment coefficient reference threshold. Based on the comparison result, it is determined whether the vibration of the camera lens will affect the SFR test, and the working states of the position adjustment structure 6, the clamping stabilization mechanism 7 and the lens position capture module 8 are controlled based on the comparison result.

[0025] It should be noted that the preset reference threshold of the vibration judgment coefficient can be determined in a variety of ways, usually based on experimental data, camera performance standards and actual application requirements. Specifically, it can be determined by the following methods: First, by conducting multiple field tests, collecting performance data of the camera under different vibration conditions, and analyzing the impact of vibration on the SFR test results, and then determining a reasonable vibration threshold; secondly, according to the physical properties of the lens such as weight, material, structure, etc. and performance requirements, set a preliminary vibration tolerance range; finally, refer to the test data of industry standards or similar equipment, combined with the vibration range allowed in actual applications, and make adjustments and optimizations. The central processor 5 will use this set reference threshold to compare the vibration judgment coefficient calculated in real time with it. When the vibration exceeds the threshold, the system automatically takes measures to reduce the impact of vibration on image quality and ensure the accuracy of the SFR test.

[0026] It should be further explained that the image analyzer 2 is responsible for real-time analysis of the image captured by the camera and performs SFR spatial frequency response test. First, the image analyzer 2 receives the image data captured by the camera and analyzes the spatial frequency and clarity in the image through image processing algorithms such as Fourier transform, edge detection, contrast analysis, etc. The image analyzer 2 calculates the SFR value of the image, which reflects the resolution capability of the image at different spatial frequencies. By comparing the difference between the test pattern and the image captured by the camera, the image analyzer 2 can accurately evaluate the resolution performance of the camera. The image analyzer 2 is usually equipped with a powerful central processing unit CPU and an image processing chip, which can quickly process large amounts of image information and generate a detailed report on image quality to determine whether the imaging quality of the camera meets the standard requirements.

[0027] The measurement pattern generator 4 is responsible for providing standardized test patterns for the camera to perform SFR testing. The generator is usually composed of a high-resolution display, a projection device or a precision printer, and is capable of generating standard patterns with specific spatial frequencies, contrasts, and geometric shapes. These patterns include grids, sine waves, lines, grayscale gradients, etc., which are used to test the imaging capabilities of the camera at different focal lengths and shooting distances. The measurement pattern generator 4 simulates different scenes in the actual shooting environment by adjusting the details and complexity of the pattern, thereby helping to evaluate the resolution performance of the camera under various conditions. The generated pattern can be displayed with a fixed resolution and contrast to ensure consistency and reliability during the image acquisition process, and provide accurate comparison data for the image analyzer 2.

[0028] In this embodiment, the position adjustment mechanism 6 includes a motor mounting frame 601, a motor 602, a gear transmission box 603, a screw 604 and a sliding frame 605. One side of the motor mounting frame 601 is fixedly connected to the inner wall of the body 1, the top of the motor mounting frame 601 is fixedly connected to the bottom of the motor 602, the output shaft of the motor 602 is transmission-connected to the input shaft of the gear transmission box 603, the output shaft of the gear transmission box 603 is transmission-connected to one end of the screw 604, and the outer wall of the screw 604 is transmission-connected to the inner wall of the sliding frame 605.

[0029] It should be noted that the gear transmission box 603 mainly transmits the rotational kinetic energy transmitted by the motor 602 to the screw 604 through its internal gear cooperation, and then controls the screw 604 to rotate. The cooperation method of the internal gears of the gear transmission box 603 is not specifically limited here and can be selected according to actual needs.

[0030] In this embodiment, the clamping stabilization mechanism 7 includes a cylinder mounting frame 701, a cylinder 702, a telescopic rod 703, an arc-shaped sponge plate 704 and an arc-shaped sponge board 705. One side of the cylinder mounting frame 701 is fixedly connected to one side of the sliding frame 605, the top of the cylinder mounting frame 701 is fixedly connected to the bottom of the cylinder 702, the output end of the cylinder 702 is transmission-connected to one end of the telescopic rod 703, the other end of the telescopic rod 703 is fixedly connected to one side of the arc-shaped sponge plate 704, and the inner side wall of the arc-shaped sponge plate 704 is fixedly connected to the outer wall of the arc-shaped sponge board 705.

[0031] The clamping and stabilizing mechanism 7 is used to clamp and fix the camera lens to prevent the camera lens from vibrating. The position adjustment mechanism 6 is used to control the clamping and stabilizing mechanism 7 to accurately move to the position of clamping and fixing the camera lens. The specific implementation method is as follows: the position adjustment mechanism 6 supports the motor 602 through the motor mounting frame 601, and transmits the rotational power of the motor 602 to the gear transmission box 603, thereby driving the rotation of the screw rod 604. The rotation of the screw rod 604 drives the sliding frame 605 to translate along its track, ensuring that the cylinder mounting frame 701 of the clamping and stabilizing mechanism 7 can accurately move to the clamping position of the camera lens inside the body 1. When the sliding frame 605 moves, it drives the cylinder mounting frame 701 to be fixed at the corresponding position, and the cylinder 702 set on the cylinder mounting frame 701 drives the telescopic movement of the telescopic rod 703 through its output end to control the position of the arc clamping plate 704. The arc clamping plate 704 is fixedly connected to the arc sponge plate 705. Under the action of the telescopic rod 703, the arc clamping plate 704 will surround and clamp the camera lens to ensure the stability of the lens and prevent vibration. At this time, the clamping and stabilizing mechanism 7 stabilizes the position of the camera lens through the buffering effect of its arc clamping plate 704 and the arc sponge plate 705. Through this cooperation, the position adjustment mechanism 6 ensures that the clamping and stabilizing mechanism 7 can accurately move to the lens position and clamp it, thereby preventing the camera lens from losing focus due to vibration during the focus adjustment process.

[0032] In this embodiment, the output end of the central processor 5 is electrically connected to the input end of the motor 602, the input end of the cylinder 702, the input end of the image analyzer 2, and the input end of the measurement pattern generator 4, and the output end and input end of the lens position capture module 8, the output end and input end of the vibration amplitude acquisition module 9, and the output end and input end of the vibration frequency acquisition module 10 are electrically connected to the input end and output end of the central processor 5 respectively; It should be noted that electrical connection refers to the process of transmitting electric current from one part of an electronic device or circuit to another part through conductive materials or conductive elements. This connection is a key component of the operation of electronic devices and circuits. It ensures the effective transmission and connection of electron flow in electronic devices. Electrical connection can be made using wires. The electrical connection method between the central processing unit 5 and the motor 602, cylinder 702, image analyzer 2, measurement pattern generator 4, lens position capture module 8, vibration amplitude acquisition module 9 and vibration frequency acquisition module 10 is not specifically limited and can be selected according to actual needs.

[0033] When adjusting the focal length, especially when the focal length changes greatly, such as from telephoto to wide angle, the optical components inside the telescopic camera lens need to be displaced to a large extent. Since the lens of the telescopic camera will move outward or inward during the focal length adjustment process, if the lens after the focal length adjustment lacks sufficient support and stability, it may vibrate slightly, resulting in defocus at the moment the image is captured. This situation is particularly obvious when the focal length adjustment range is large. However, the existing camera SFR test device with adjustable focal length function cannot effectively stabilize the position of the telescopic camera lens after the focal length is adjusted, so it is impossible to avoid the vibration of the lens after the focal length adjustment, resulting in the image being out of focus during shooting, which in turn makes the test image blurred. This will directly affect the accuracy of the SFR test, resulting in a low SFR calculation result, making the test data unreliable.

[0034] Therefore, it is of great significance to solve this technical problem. Lens vibration and defocusing during the focal length adjustment process will directly affect the clarity of the image, which will lead to inaccurate SFR test data. Especially in the case of a large change in focal length, the optical components of the telescopic camera will undergo a large displacement. At this time, the lens lacks sufficient support and stability, and is prone to vibration or rebound, resulting in blurred images. By setting a clamping stabilization mechanism 7 and a position adjustment mechanism 6, precise lens support and stability can be provided after the focal length is adjusted, avoiding the impact of vibration on image quality and test results. This solution not only improves the lens stability during the focal length adjustment process, but also ensures the accuracy of the SFR test, avoids errors caused by defocus, and makes the image data more reliable, thereby improving the overall performance and application value of the test equipment.

[0035] In this embodiment, the vibration amplitude variation coefficient is a parameter calculated by analyzing the vibration amplitude of the camera lens in different time periods. Specifically, AVC collects the vibration amplitude of the camera at different times during the focal length adjustment process, and combines the processing of the vibration data by the central processor 5 to calculate the change in the vibration amplitude. The size of AVC reflects the degree of change in the vibration amplitude of the camera lens. The larger the value, the more significant the change in the vibration amplitude and the worse the lens stability. In the SFR test, the higher the AVC value, the greater the impact of the vibration on the lens, which is more likely to cause the image to be out of focus and the test result to be inaccurate. Therefore, the size of AVC is closely related to determining whether the vibration of the camera lens will affect the SFR test.

[0036] The logic for obtaining the vibration amplitude variation coefficient is: S1. The vibration amplitude acquisition module 9 obtains the vibration amplitude of the camera lens at different times within a period of time in real time and calibrates it as , Indicates that the camera lens is within a period of time The vibration amplitude at the moment, , is a positive integer; To obtain the vibration amplitude of the camera lens at different times over a period of time in real time, a variety of sensors or devices can be used to capture vibration signals. Common implementation methods include: acceleration sensors, which reflect the vibration amplitude by measuring the acceleration changes of the camera lens in different directions; displacement sensors, which obtain vibration amplitude information by accurately measuring the tiny displacement changes of the lens; piezoelectric sensors, which use the piezoelectric effect to detect force changes caused by vibration and convert them into electrical signals; and optical sensors, which capture the vibration amplitude by measuring changes in the lens surface or other reference points. These sensors collect vibration data in real time and convert it into digital signals through analog-to-digital conversion technology. The data is then transmitted to the central processor through communication interfaces such as I2C or SPI for further analysis and processing, thereby obtaining and monitoring changes in the lens vibration amplitude in real time.

[0037] S2, obtaining the preset maximum vibration amplitude of the camera lens allowed by the central processor 5, and calibrating it as ; The preset maximum vibration amplitude of the camera lens allowed is obtained by the central processor 5, which is usually achieved by a pre-set maximum vibration amplitude threshold. These preset maximum vibration amplitudes can be determined based on experimental data, physical characteristics of the camera or industry standards. The acquisition method includes: setting a threshold when the system is initialized, defining the threshold through user input or standardized test settings; or dynamically adjusting the maximum vibration amplitude according to historical test data and lens performance requirements. The central processor 5 will read these preset vibration amplitude thresholds and compare them with the vibration amplitude collected in real time to determine whether the current vibration amplitude exceeds the allowable range. If the real-time data exceeds the preset threshold, the central processor will initiate corresponding control measures to ensure the stability of the lens and avoid vibration affecting the SFR test results. The specific method for obtaining the preset maximum vibration amplitude is not specifically limited here and can be selected according to actual needs.

[0038] S3. The vibration amplitude of the camera lens at different times within a period of time Create a collection and add the vibration amplitudes in the collection that are greater than the preset maximum The vibration amplitude is recalibrated as , Indicates that the vibration amplitude in the set is greater than the preset maximum The vibration amplitude number, , is a positive integer; S4. Calculate the vibration amplitude variation coefficient. The calculation expression is: In the formula, is the coefficient of variation of vibration amplitude.

[0039] In this embodiment, the vibration frequency deviation index is a parameter obtained by analyzing and calculating the deviation of the camera lens vibration frequency, which reflects the frequency change of the lens vibration. Specifically, FDC is obtained by collecting the vibration frequency of the camera at different time points and calculating the deviation between it and the preset maximum vibration frequency ZPMAX. The size of FDC is directly related to the frequency deviation of the lens vibration. The larger the value, the greater the frequency deviation of the lens vibration. The higher the vibration frequency deviation index, the more drastic the vibration frequency change of the camera lens, which may lead to unstable focal length adjustment, affect the focusing effect of the lens, and further affect the accuracy of the SFR test.

[0040] The logic for obtaining the vibration frequency deviation index is: S1. The vibration frequency of the camera at different times within a period of time is obtained in real time through the vibration frequency acquisition module 10, and calibrated as , Indicates that the camera is within a period of time The vibration frequency of the moment, , is a positive integer; Real-time acquisition of the vibration frequency of the camera at different times over a period of time can be achieved through a variety of sensors or devices. Common methods include using accelerometers, gyroscopes or vibration sensors. Accelerometers can measure the acceleration changes of the camera in different directions, and the frequency of vibration can be calculated through these acceleration signals. Gyroscopes can detect changes in the rotation angle of the lens, further reflecting the frequency characteristics of vibration. Vibration sensors, especially piezoelectric sensors, can capture the frequency of vibration by sensing the tiny force changes caused by vibration. The above sensors will convert the captured vibration signals into electrical signals and transmit them to the central processor in real time through the data acquisition system for analysis and processing. These real-time data can help the system accurately monitor the vibration frequency of the lens, and then determine the impact of vibration on focus adjustment and image quality.

[0041] S2, obtaining the preset maximum vibration frequency of the camera allowed by the central processor 5, and calibrating it as ; The preset maximum vibration frequency of the camera allowed is obtained by the central processor 5, which is usually achieved through a pre-set maximum vibration frequency threshold. This threshold can be set according to the design specifications, performance standards and actual application requirements of the camera. The acquisition method includes: setting the maximum vibration frequency through user input or standardized test data when the system is initialized; or dynamically adjusting the threshold based on historical test data and the physical characteristics of the camera lens. The central processor 5 will read these preset maximum vibration frequency values ​​and use them as a reference to compare with the vibration frequency data collected in real time. If the real-time frequency exceeds the preset threshold, the system can determine that the vibration has exceeded the tolerance range, thereby triggering an automatic adjustment mechanism to avoid the impact of vibration on focal length adjustment and image quality. The specific method for obtaining the preset maximum vibration frequency is not specifically limited here and can be selected according to actual needs.

[0042] S3. Calculate the vibration frequency deviation index. The calculation expression is: In the formula, is the vibration frequency deviation index.

[0043] In this embodiment, the vibration determination coefficient is expressed as: Will and After dimensionless processing, the central processing unit 5 performs a formula analysis according to the formula: In the formula, is the vibration determination coefficient, and are the vibration amplitude variation coefficients and vibration frequency deviation index The preset scaling factor of and All are greater than 0; From the calculated expression, we can know that the vibration amplitude variation coefficient and vibration frequency deviation index The larger the value, the greater the vibration judgment coefficient the bigger it is; It should be noted that dimensionless is a process of expressing physical quantities in dimensionless form. This method can eliminate the influence of units on physical problems, making the problem more concise and universal; the vibration amplitude variation coefficient and vibration frequency deviation index Preset scaling factor and In order to more flexibly adapt to different working conditions and environmental changes in actual monitoring, these deviation coefficients can be adjusted according to specific circumstances to improve the performance and applicability of the monitoring system.

[0044] In this embodiment, the preset vibration determination coefficient reference threshold is set to , the vibration determination coefficient calculated by the central processing unit 5 and the preset vibration judgment coefficient reference threshold A comparison is performed, and it is determined whether the vibration of the camera lens will affect the SFR test according to the comparison result, and the working states of the position adjustment structure 6, the clamping stabilization mechanism 7 and the lens position capture module 8 are controlled according to the comparison result. The specific determination is as follows: when When the vibration of the camera lens does not affect the SFR test, a normal signal is generated. After receiving the normal signal, the central processor 5 generates a standby signal and transmits it to the motor 602, the cylinder 702 and the lens position capture module 8 respectively. After receiving the standby signal, the motor 602 and the cylinder 702 respectively control the position adjustment structure 6 and the clamping stabilization mechanism 7 to perform standby work. After receiving the standby signal, the lens position capture module 8 also performs standby work; Standby operation refers to a low-power, non-action state that a device or system enters when there is no abnormal situation or adjustment required, in order to maintain the stability of the system and save energy. In this solution, when the vibration of the camera lens does not affect the SFR test, the central processor 5 generates a standby signal. After receiving the standby signal, the motor 602 and the cylinder 702 will control the position adjustment structure 6 and the clamping stabilization mechanism 7 to enter the standby working state, which means that these components stop making any adjustments or actions and maintain the current stable state; after receiving the standby signal, the lens position capture module 8 also enters the standby working state and stops real-time monitoring of the lens position. The standby working state ensures that the system is in an energy-saving and non-operational state, avoiding unnecessary operations or energy consumption until the corresponding module is activated when operation or adjustment is required.

[0045] when When the camera lens is in the state of being moved, the vibration of the camera lens will affect the SFR test and generate an abnormal signal. After receiving the abnormal signal, the central processing unit 5 generates a capture signal, a movement signal and a clamping signal, and transmits the capture signal to the lens position capture module 8. After receiving the capture signal, the lens position capture module 8 performs the lens position capture work, and transmits the movement signal to the motor 602. After receiving the movement signal, the motor 602 controls the position adjustment structure 6 to perform the position adjustment work, and transmits the clamping signal to the cylinder 702. After receiving the clamping signal, the cylinder 702 controls the clamping stabilization mechanism 7 to perform the clamping stabilization work.

[0046] The lens position capture work refers to the real-time acquisition of the position information of the camera lens by the lens position capture module 8 after receiving the capture signal, and transmitting it to the central processor 5 for analysis to determine the position of the camera lens. The lens position capture module 8 obtains the precise position data of the lens by monitoring the position changes of the camera lens in real time. This is usually done by using a position sensor such as an accelerometer, an optical encoder or a capacitive displacement sensor. The sensor detects the slight movement of the lens and generates a signal, which is transmitted to the central processor 5. This work can ensure that when the camera lens vibrates or changes position, the system can accurately know the position of the lens, and provide real-time data for subsequent adjustment and stabilization work. The reason why the lens position capture work is needed is to ensure that the lens position can be adjusted in time under vibration conditions to prevent defocusing caused by lens displacement, thereby ensuring the accuracy of the SFR test results.

[0047] Position adjustment means that after receiving the movement signal, the motor 602 transmits the output rotational power to the gear transmission box 603, thereby driving the rotation of the screw rod 604. The rotation of the screw rod 604 drives the sliding frame 605 to translate along its track, ensuring that the cylinder mounting frame 701 of the clamping stabilizing mechanism 7 can accurately move inside the body 1 to the clamping position of the camera lens.

[0048] The clamping and stabilizing work means that after the cylinder 702 receives the clamping signal, it drives the telescopic rod 703 to move telescopically through its output end, and controls the position of the arc-shaped clamping plate 704. Under the action of the telescopic rod 703, the arc-shaped clamping plate 704 will surround and clamp the camera lens to ensure the stability of the lens and prevent vibration. At this time, the clamping and stabilizing mechanism 7 stabilizes the position of the camera lens through the buffering effect of its arc-shaped clamping plate 704 and the arc-shaped sponge plate 705.

[0049] The above formulas are all dimensionless and numerical calculations. The formula is a formula for the most recent real situation obtained by collecting a large amount of data and performing software simulation. The preset parameters in the formula are set by technicians in this field according to actual conditions.

[0050] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0051] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0052] In the several embodiments provided in the present application, it should be understood that the disclosed overall system, device and method can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another overall system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0053] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0054] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0055] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A camera SFR test device with a focus adjustable function, comprising a body (1), an image analyzer (2) for analyzing an image captured by a camera and performing an SFR test, a mounting base (3) for mounting the camera, and a measurement pattern generator (4) for providing a measurement pattern, characterized in that: A central processing unit (5) is provided on one side of the image analyzer (2), and a position adjustment structure (6) and a clamping stabilization mechanism (7) are provided on the inner side of the body (1), wherein the clamping stabilization mechanism (7) is used to clamp and fix the camera lens to prevent the camera lens from vibrating, and the position adjustment mechanism (6) is used to control the clamping stabilization mechanism (7) to accurately move to a position for clamping and fixing the camera lens; Also includes: A lens position capture module (8) is arranged on the inner bottom wall of the body (1) and is used to obtain the position information of the camera lens in real time and transmit it to the central processor (5) for analysis to determine the position of the camera lens; A vibration amplitude acquisition module (9) is arranged on the inner bottom wall of the body (1) and is used to obtain the vibration amplitude of the camera lens at different times within a period of time in real time, and to generate a vibration amplitude variation coefficient through a central processor (5); A vibration frequency acquisition module (10) is arranged on the inner side wall of the mounting seat (3) and is used to acquire the vibration frequency of the camera at different times within a period of time in real time, and to generate a vibration frequency deviation index through a central processing unit (5); The generated vibration amplitude variation coefficient and vibration frequency deviation index are comprehensively analyzed by a central processing unit (5) to generate a vibration judgment coefficient, which is then compared with a preset vibration judgment coefficient reference threshold value. Based on the comparison result, it is determined whether the vibration of the camera lens will affect the SFR test, and the working states of the position adjustment structure (6), the clamping stabilization mechanism (7) and the lens position capture module (8) are controlled based on the comparison result.

2. The camera SFR test device with adjustable focus according to claim 1, characterized in that: The position adjustment mechanism (6) comprises a motor mounting frame (601), a motor (602), a gear transmission box (603), a screw rod (604) and a sliding frame (605); one side of the motor mounting frame (601) is fixedly connected to the inner wall of the machine body (1); the top of the motor mounting frame (601) is fixedly connected to the bottom of the motor (602); the output shaft of the motor (602) is drivingly connected to the input shaft of the gear transmission box (603); the output shaft of the gear transmission box (603) is drivingly connected to one end of the screw rod (604); and the outer wall of the screw rod (604) is drivingly connected to the inner wall of the sliding frame (605).

3. The camera SFR test device with adjustable focus according to claim 2, characterized in that: The clamping stabilization mechanism (7) comprises a cylinder mounting frame (701), a cylinder (702), a telescopic rod (703), an arc-shaped clamping plate (704) and an arc-shaped sponge plate (705); one side of the cylinder mounting frame (701) is fixedly connected to one side of the sliding frame (605); the top of the cylinder mounting frame (701) is fixedly connected to the bottom of the cylinder (702); the output end of the cylinder (702) is transmission-connected to one end of the telescopic rod (703); the other end of the telescopic rod (703) is fixedly connected to one side of the arc-shaped clamping plate (704); and the inner side wall of the arc-shaped clamping plate (704) is fixedly connected to the outer wall of the arc-shaped sponge plate (705).

4. The camera SFR test device with adjustable focus according to claim 3, characterized in that: The output end of the central processing unit (5) is electrically connected to the input end of the motor (602), the input end of the cylinder (702), the input end of the image analyzer (2), and the input end of the measurement pattern generator (4), respectively; the output end and input end of the lens position capture module (8), the output end and input end of the vibration amplitude acquisition module (9), and the output end and input end of the vibration frequency acquisition module (10) are electrically connected to the input end and output end of the central processing unit (5), respectively.

5. The camera SFR test device with adjustable focus according to claim 4, characterized in that: The acquisition logic of the vibration amplitude variation coefficient is: S1. The vibration amplitude of the camera lens at different times within a period of time is obtained in real time through the vibration amplitude acquisition module (9), and calibrated as , Indicates that the camera lens is within a period of time The vibration amplitude at the moment, , is a positive integer; S2. Obtain the preset maximum vibration amplitude of the camera lens allowed by the central processor (5) and calibrate it as ; S3. The vibration amplitude of the camera lens at different times within a period of time Create a collection and add the vibration amplitudes in the collection that are greater than the preset maximum The vibration amplitude is recalibrated as , Indicates that the vibration amplitude in the set is greater than the preset maximum The vibration amplitude number, , is a positive integer; S4. Calculate the vibration amplitude variation coefficient. The calculation expression is: In the formula, is the vibration amplitude variation coefficient.

6. The camera SFR test device with adjustable focus according to claim 5, characterized in that: The acquisition logic of the vibration frequency deviation index is: S1. Obtain the vibration frequency of the camera at different times within a period of time in real time through the vibration frequency acquisition module (10), and calibrate it as , Indicates that the camera is within a period of time The vibration frequency of the moment, , is a positive integer; S2. Obtain the preset maximum vibration frequency of the camera allowed by the central processor (5) and calibrate it as ; S3. Calculate the vibration frequency deviation index. The calculation expression is: In the formula, is the vibration frequency deviation index.

7. The camera SFR testing device with adjustable focus according to claim 6, characterized in that: The expression formula of the vibration judgment coefficient is: The central processing unit (5) performs a formula analysis according to the formula: In the formula, is the vibration determination coefficient, and are the vibration amplitude variation coefficients and vibration frequency deviation index The preset scaling factor of and Both are greater than 0.

8. The camera SFR testing device with adjustable focus according to claim 7, characterized in that: Set the preset vibration judgment coefficient reference threshold to , the calculated vibration judgment coefficient is converted into and the preset vibration judgment coefficient reference threshold A comparison is performed, and based on the comparison result, it is determined whether the vibration of the camera lens will affect the SFR test, and based on the comparison result, the working states of the position adjustment structure (6), the clamping stabilization mechanism (7) and the lens position capture module (8) are controlled. The specific determination is as follows: when When the vibration of the camera lens does not affect the SFR test, a normal signal is generated. After receiving the normal signal, the central processing unit (5) generates a standby signal and transmits it to the motor (602), the cylinder (702) and the lens position capture module (8) respectively. After receiving the standby signal, the motor (602) and the cylinder (702) respectively control the position adjustment structure (6) and the clamping stabilization mechanism (7) to perform standby work. After receiving the standby signal, the lens position capture module (8) also performs standby work; when When the camera lens is in a state of vibration, the vibration will affect the SFR test and generate an abnormal signal. After receiving the abnormal signal, the central processing unit (5) generates a capture signal, a movement signal and a clamping signal, and transmits the capture signal to the lens position capture module (8). After receiving the capture signal, the lens position capture module (8) performs a lens position capture operation and transmits the movement signal to the motor (602). After receiving the movement signal, the motor (602) controls the position adjustment structure (6) to perform a position adjustment operation and transmits the clamping signal to the cylinder (702). After receiving the clamping signal, the cylinder (702) controls the clamping stabilization mechanism (7) to perform a clamping stabilization operation.

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