Auto-focusing method and system for TFT-LCD photosensitive array board

Abstract

The present invention provides an autofocus method and system for a TFT-LCD photosensitive array panel; the imaging device sends an infrared or ultrasonic signal to an object, and after the infrared or ultrasonic signal is reflected back by the object, it is converted into an electrical signal by the photosensitive elements of the TFT-LCD photosensitive array panel; the signal processor converts the electrical signal into a digital signal, processes the digital signal, and transmits the processed digital signal to the image processor; the image processor converts the received digital signal into an image and analyzes the image, and the analysis includes edge detection and contrast analysis. This solution can ensure the accuracy of the correspondence between the pixels on the photosensitive array panel and the image signal, thus avoiding image blurring and distortion problems caused by inaccurate focusing; by adopting the autofocus method, it is possible to avoid the errors and time consumption brought about by manual adjustment of the photosensitive array panel by human intervention.

Description

Technical Field

[0001] The present invention provides an autofocus method and system for a TFT-LCD photosensitive array panel, belonging to the technical field of liquid crystal display. Background Art

[0002] With the progress of technology, autofocus technology has become an important function in photographic equipment. However, traditional autofocus methods mainly rely on the brightness change of images or the movement of objects to detect the change of focus. This method may have problems of inaccurate focusing or slow focusing speed in some cases. Especially when shooting dynamic images or under low light conditions, the performance of these methods will be limited. Therefore, a new autofocus method is needed to improve the shooting quality. A TFT-LCD (Thin-Film Transistor Liquid Crystal Display) photosensitive array panel is an electronic device that can convert received infrared or ultrasonic signals into electrical signals. This conversion process is based on the response of photosensitive elements to infrared or ultrasonic signals. This technology has been widely used in various image and signal acquisition systems. Summary of the Invention

[0003] The present invention provides an autofocus method and system for a TFT-LCD photosensitive array panel to solve the problem that existing shooting devices cannot obtain clear images due to inaccurate focus positions during the autofocus process:

[0004] The autofocus method for a TFT-LCD photosensitive array panel proposed by the present invention includes:

[0005] S1: The shooting device sends an infrared or ultrasonic signal to an object. After the infrared or ultrasonic signal is reflected by the object, it is converted into an electrical signal by the photosensitive elements of the TFT-LCD photosensitive array panel;

[0006] S2: The signal processor converts the electrical signal into a digital signal, processes the digital signal, and transmits the processed digital signal to the image processor; the image processor converts the received digital signal into an image and analyzes the image. The analysis includes edge detection and contrast analysis; and the position of the best focus point is obtained according to the analysis result;

[0007] S3: According to the position of the best focus point, adjust the position of the shooting device and perform shooting.

[0008] Furthermore, the process of the shooting device sending an infrared or ultrasonic signal to an object and converting the infrared or ultrasonic signal into an electrical signal by the photosensitive elements of the TFT-LCD photosensitive array panel after the signal is reflected by the object is as follows:

[0009] S11: Send an infrared or ultrasonic signal to the object to be photographed by a photographing device;

[0010] S12: The infrared or ultrasonic signal reaches the object surface, is reflected back to become an optical signal, and is received by a receiver;

[0011] S13: The receiver transmits the received optical signal to a TFT-LCD photosensitive array board;

[0012] S14: The photosensitive array board senses the intensity and position of the optical signal; and converts the sensed optical signal into an electrical signal through photosensitive elements.

[0013] Further, the image processor converts the received digital signal into an image and analyzes the image. The analysis includes edge detection and contrast analysis; and obtains the position of the best focus point according to the analysis result, including:

[0014] S21: The signal processor converts the electrical signal into a digital signal through an analog-to-digital converter; and processes the digital signal. The processing includes filtering, amplification, and sampling;

[0015] S22: Send the processed digital signal to the image processor. After receiving the digital signal, the image processor processes the digital signal. The processing includes adjusting brightness, contrast, and color balance, removing noise, and sharpening and blurring;

[0016] S23: The image processor generates a new digital image according to the processed digital signal, and extracts the features required for the focus point from the new digital image through an edge detection algorithm. The features include sharpness, contrast, and high-frequency signals;

[0017] S24: Match the extracted features with the standard features to find the area in the new digital image that conforms to the standard features; the conforming area is the position of the best focus point;

[0018] S25: Output the new digital image and the position information of the extracted best focus point.

[0019] Further, adjusting the position of the photographing device according to the position of the best focus point and taking a photograph includes:

[0020] S31: Determine the distance of the position where the best focus point is located, adjust the focal length of the lens, and adjust the position of the best focus point to within the clear focus range;

[0021] S32: According to the position of the best focus point, adjust the position and direction of the photographing device, and switch the focusing mode to single-shot autofocus mode, confirm the position of the best focus point and make adjustments;

[0022] S33: When the shooting device accurately focuses on the optimal focus point, execute the shooting instruction to take a picture.

[0023] The automatic focusing system for the TFT-LCD photosensitive array board provided by the present invention, the system includes:

[0024] Light sensing module: The shooting device sends an infrared or ultrasonic signal to an object, and after the infrared or ultrasonic signal is reflected back by the object, it is converted into an electrical signal through the photosensitive element of the TFT-LCD photosensitive array board;

[0025] Signal processing module: The signal processor converts the electrical signal into a digital signal, processes the digital signal, and transmits the processed digital signal to the image processor; the image processor converts the received digital signal into an image and analyzes the image, and the analysis includes edge detection and contrast analysis; and obtains the position where the optimal focus point is located according to the analysis result;

[0026] Automatic focusing module: Adjust the position of the shooting device according to the position of the optimal focus point and take a picture.

[0027] Further, the light sensing module includes:

[0028] Transmission module: Send an infrared or ultrasonic signal to the shooting object through the shooting device;

[0029] Reflection module: The infrared or ultrasonic signal reaches the surface of the object and is reflected back to become an optical signal and is received by the receiver;

[0030] Receiving module: The receiver transmits the received optical signal to the TFT-LCD photosensitive array board;

[0031] Sensing module: The photosensitive array board senses the intensity and position of the optical signal; and converts the sensed optical signal into an electrical signal through the photosensitive element.

[0032] Further, the signal processing module includes:

[0033] Analog-to-digital conversion module: The signal processor converts the electrical signal into a digital signal through an analog-to-digital converter; and processes the digital signal, and the processing includes filtering, amplification and sampling;

[0034] Image processing module: Send the processed digital signal to the image processor, and the image processor processes the digital signal after receiving it, and the processing includes adjusting brightness, contrast and color balance, removing noise, and sharpening and blurring;

[0035] Feature extraction module: The image processor generates a new digital image based on the processed digital signal, and extracts the features required for the focus point from the new digital image through an edge detection algorithm. The features include sharpness, contrast, and high-frequency signals.

[0036] Feature matching module: Matches the extracted features with the standard features to find the area in the new digital image that conforms to the standard features. The conforming area is the location of the best focus point.

[0037] Information output module: Outputs the new digital image and the position information of the extracted best focus point.

[0038] Further, the autofocus module includes:

[0039] Position adjustment module: Adjusting the position of the shooting device according to the position of the best focus point and performing shooting includes:

[0040] Distance determination module: Determines the distance of the position where the best focus point is located, adjusts the focal length of the lens, and adjusts the position of the best focus point to the clear focus range.

[0041] Position determination module: According to the position of the best focus point, adjusts the position and direction of the shooting device, and switches the focus mode to single autofocus mode, confirms the position of the best focus point and makes adjustments.

[0042] Shooting execution module: When the shooting device is accurately focused on the best focus point, executes the shooting instruction to take a picture.

[0043] An electronic device provided by the present invention includes a memory, a processor, and a computer program stored on the memory and executable on the memory. The processor executes the program to implement the autofocus method for the TFT-LCD photosensitive array board as described in any one of the above.

[0044] A non-transitory computer-readable storage medium provided by the present invention stores a computer program thereon, and the program is executed by a processor to implement the autofocus method for the TFT-LCD photosensitive array board as described in any one of the above.

[0045] Advantages of the present invention: The autofocus method provided by the present invention can ensure the accuracy of the correspondence between the pixels on the photosensitive array board and the image signals, thereby avoiding image blurring and distortion problems caused by inaccurate focusing; by using the autofocus method, it is possible to avoid the errors and time consumption brought about by manual adjustment of the photosensitive array board by human intervention; reduce potential errors caused by human factors and improve the reliability and stability of the device; the autofocus method can complete calibration quickly and efficiently, and at the same time can monitor the status of the photosensitive array board at any time, detect and eliminate system failures in a timely manner, and ensure the stable and reliable operation of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 It is a flowchart of the steps of the autofocus method for the TFT-LCD photosensitive array board of the present invention;

[0047] Figure 2 It is a block diagram of the autofocus system for the TFT-LCD photosensitive array board of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0048] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other.

[0049] In the following description, many specific details are set forth in order to fully understand the present invention. The described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0050] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments, and are not intended to limit the present invention.

[0051] An embodiment of the present invention, an autofocus method for a TFT-LCD photosensitive array board, the method includes:

[0052] S1: The imaging device sends an infrared or ultrasonic signal to the object, and after the infrared or ultrasonic signal is reflected back by the object, it is converted into an electrical signal by the photosensitive element of the TFT-LCD photosensitive array board;

[0053] S2: The signal processor converts the electrical signal into a digital signal, processes the digital signal, and transmits the processed digital signal to the image processor; the image processor converts the received digital signal into an image and analyzes the image, and the analysis includes edge detection and contrast analysis; and obtains the position of the best focus point according to the analysis result.

[0054] S3: Adjust the position of the shooting device according to the position of the best focus point and take a picture.

[0055] The working principle of the above technical solution is as follows: The shooting device sends infrared or ultrasonic signals to the object. After being reflected by the object, these signals will be sensed by the photosensitive element and converted into electrical signals; the photosensitive element converts the sensed optical signal into an electrical signal and transmits it to the signal processor for digital signal processing. In this step, the signal processor can perform operations such as amplifying and filtering the electrical signal to improve the perception ability of the reflected signal; after the digital signal processing is completed, the image processor will convert the received digital signal into an image and analyze the image. Specifically, the image processor will perform operations such as edge detection and contrast analysis to determine the best focus position; according to the position of the best focus point, the shooting device will automatically adjust the position and perform the shooting operation. By continuously repeating the above steps, the continuous autofocus function for the object can be achieved.

[0056] The effects of the above technical solution are as follows: The above technical solution uses a TFT-LCD photosensitive array board to sense light, and through effective image analysis of digital signal processing, the focusing accuracy and speed are improved; this method does not require manual intervention, can avoid errors and time waste caused by manual operation, and improves production efficiency; the above autofocus method can focus quickly and accurately, thereby improving the image quality and enabling users to take clearer and more beautiful photos or videos; the above autofocus method can dynamically adjust calibration parameters according to the real-time feedback signal, so as to adapt to different lighting environments and changes in the characteristics of the photosensitive array board; the above autofocus method can monitor the state of the photosensitive array board at any time, discover and eliminate system faults in time, and ensure the stable and reliable operation of the system.

[0057] An embodiment of the present invention: The process of converting the infrared or ultrasonic signal reflected by the object into an electrical signal through the photosensitive element of the TFT-LCD photosensitive array board after the shooting device sends the infrared or ultrasonic signal to the object is as follows:

[0058] S11: Send infrared or ultrasonic signals to the shooting object through the shooting device.

[0059] S12: The infrared or ultrasonic signal reaches the surface of the object, is reflected back to become an optical signal and is received by the receiver.

[0060] S13: The receiver transmits the received optical signal to the TFT-LCD photosensitive array board;

[0061] S14: The photosensitive array board senses the intensity and position of the optical signal; and converts the sensed optical signal into an electrical signal through photosensitive elements.

[0062] The working principle of the above technical solution is as follows: An infrared or ultrasonic signal is sent to the photographed object by a photographing device; when the sent signal reaches the object surface, a part of it is absorbed by the object, and the other part is reflected back by the object surface; after the reflected signal becomes an optical signal, it reaches the photographing device again and is received by the receiver; the receiver transmits the received optical signal to the TFT-LCD photosensitive array board, and the TFT-LCD photosensitive array board senses the intensity and position of the reflected optical signal; and converts the sensed optical signal into an electrical signal through photosensitive elements.

[0063] The effects of the above technical solution are as follows: The autofocus function can greatly improve the shooting efficiency and quality, making the photos clearer and the details more distinct; by utilizing the characteristic of the TFT-LCD photosensitive array board to sense light, this technology can quickly and accurately complete the autofocus adjustment, avoiding the cumbersome and inaccurate manual focusing operation; the above technical solution can work in various environments, including under conditions such as low light, reflection, and parallel light, and can obtain accurate depth information and the best focusing position; using infrared or ultrasonic signals for distance measurement can avoid the errors and blurring phenomena in traditional optical focusing systems, thereby improving the quality and clarity of the photos.

[0064] An embodiment of the present invention: The signal processor converts the electrical signal into a digital signal, processes the digital signal, and transmits the processed digital signal to the image processor; the image processor converts the received digital signal into an image and analyzes the image, and the analysis includes edge detection and contrast analysis; and obtains the position where the best focus point is located according to the analysis result, including:

[0065] S21: The signal processor converts the electrical signal into a digital signal through an analog-to-digital converter; and processes the digital signal to obtain a digital signal analysis result, and the processing includes filtering, amplification, and sampling; the result includes the spectral characteristics, peak value, time domain, and frequency domain of the signal;

[0066] S22: Transmit the processed digital signal to the image processor, and after the image processor receives the digital signal, it processes the digital signal to obtain an image with adjusted brightness, contrast, and color balance, an image after denoising processing, and an image after sharpening and blurring processing; the processing includes brightness, contrast, and color balance adjustment, noise removal, and sharpening and blurring;

[0067] S23: The image processor generates a new digital image based on the processed digital signal, and extracts the features required for the focus point from the new digital image through an edge detection algorithm. The features include sharpness, contrast, and high-frequency signals;

[0068] Among them, extracting the features required for the focus point from the new digital image includes converting the color image into a grayscale image; using a smoothing filter, such as a Gaussian filter or a median filter, to reduce noise; using operators such as Sobel, Prewitt, and Roberts to calculate the gradient magnitude and direction at each pixel point; for each pixel point, only retaining the local maximum in its gradient direction and suppressing other non-larger local extreme points; dividing the pixel points into three categories: strong edges, weak edges, and non-edges according to preset high and low thresholds; and connecting the weak edge pixel points adjacent to the strong edge pixel points to obtain a complete edge.

[0069] Among them, the specific steps for extracting the features required for the focus point from the new digital image are as follows:

[0070] Let the new digital image be L(x, y), and its size be W*B. The calculation formula for the sharpness Q is:

[0071]

[0072] Among them and respectively represent the gray level steps of the image in the x and y directions;

[0073] The calculation formula for the contrast D is,

[0074]

[0075] Among them represents the average gray value of the image;

[0076] The calculation formula for the high-frequency signal G is:

[0077]

[0078] Among them, the ξ 2 represents the Laplacian operator, which can be implemented through the following convolution kernel,

[0079]

[0080] S24: Match the extracted features with the standard features to find the area in the new digital image that conforms to the standard features; the conforming area is the location of the best focus point;

[0081] Among them, when matching the extracted features with the standard features, the matching formula is the correlation coefficient formula, which is expressed as:

[0082]

[0083] Among them, E T and F t respectively represent the values of the t-th elements in the extracted features and the standard features, and respectively represent the means of the extracted features and the standard features. K ∈ (0, 1), and the matching is successful when K > 0.65.

[0084] S25: Output the new digital image and the position information of the extracted best focus point.

[0085] The working principle of the above technical solution is as follows: First, the signal processor converts the electrical signal into a digital signal and performs processing such as filtering, amplification, and sampling on it. Then, the processed digital signal is sent to the image processor through the analog-to-digital converter, and the image processor performs processing such as brightness, contrast, and color balance adjustment, noise removal, and sharpening and blurring on it, and generates a new digital image; Next, the image processor uses an edge detection algorithm to extract the features required for the focus point from the new digital image, including sharpness, contrast, and high-frequency signals, etc. Specifically, the algorithm includes the following steps: converting the color image into a grayscale image; using a smoothing filter to reduce noise; calculating the gradient magnitude and direction at each pixel point; for each pixel point, only retaining the local maximum value in its gradient direction and suppressing other local extreme points that are not larger; dividing the pixel points into three categories: strong, weak, and non-edge according to the preset high and low thresholds; and using adjacent weak edge pixel points to connect strong edge pixel points to obtain a complete edge; Finally, the image processor matches the extracted features with the standard features to find the area in the new digital image that conforms to the standard features, and this area is the position where the best focus point is located. At the same time, output the new digital image and the position information of the extracted best focus point.

[0086] The effects of the above technical solution are as follows: This technical solution can achieve autofocus without the need for users to manually adjust the focus, improving the accuracy and efficiency of shooting. At the same time, it can also avoid problems such as blurred and out-of-focus photos caused by improper manual focusing, providing users with a better shooting experience. The image processor adjusts the brightness, contrast, and color balance of the digital signal, removes noise, and performs processing such as sharpening and blurring, further improving the quality and clarity of the photo. Through the edge detection algorithm, this technical solution can extract the features required for the focus point in the new digital image, including sharpness, contrast, and high-frequency signals, etc., so as to find the position of the best focus point and improve the accuracy and efficiency of the shooting device. This technical solution is applicable to various types of shooting devices, including mobile phones, cameras, video cameras, etc., and can meet the needs of different users. The above feature point extraction formula can determine the position of the best focus point of the image by calculating features such as the sharpness, contrast, and high-frequency signals of the image. These features can help the autofocus system better understand the content in the image and adjust the focal length of the camera lens to obtain a clear image. At the same time, since the above formula is implemented based on digital image processing technology, it can complete autofocus without human intervention. This enables the camera to quickly adapt to different scenarios and shooting requirements to obtain the best imaging effect. The above formula takes into account multiple focus-related factors (such as sharpness, contrast, and high-frequency signals, etc.), so it can provide very accurate focus results. This enables the camera to better capture the details and contours of the object, thus obtaining a better imaging effect. The above formula is implemented based on digital signal processing technology, so it can operate without being affected by factors such as light and environmental noise. This enables the formula to maintain stable performance under various shooting conditions. At the same time, the above feature matching formula determines the degree of matching by calculating the correlation coefficient between the extracted features and the standard features, and can more precisely achieve autofocus, thereby improving the imaging quality of the camera. At the same time, the above feature matching formula can screen out the extracted features with a higher similarity to the standard features by setting the threshold K>0.65 for successful matching, thereby improving the matching success rate. The calculation speed of the correlation coefficient formula is fast, which can meet the real-time requirements and can quickly complete autofocus during shooting. This matching method is implemented based on a simple correlation coefficient formula and does not require adding other complex algorithms, so it is easy to implement and has strong practicality.

[0087] An embodiment of the present invention: The adjusting the position of the shooting device according to the position of the best focus point and performing shooting includes:

[0088] S31: Determine the distance of the position where the best focus point is located, adjust the focal length of the lens, and adjust the position of the best focus point to the clear focus range;

[0089] S32: According to the position of the optimal focus point, adjust the position and orientation of the imaging device, and switch the focusing mode to single-shot autofocus mode. Confirm the position of the optimal focus point and make adjustments; ensure that the optimal focus point is within the shooting range and is accurately focused; parameters such as the height, angle, and orientation of the camera need to be adjusted.

[0090] S33: When the imaging device is accurately focused on the optimal focus point, execute the shooting instruction to take a shot.

[0091] The working principle of the above technical solution is as follows: According to the edge detection algorithm mentioned above, the clearest part of the image, that is, the position of the optimal focus point, can be found. According to the ranging function of the camera or other distance measurement tools, determine the distance of the position where the optimal focus point is located, and adjust the focal length of the lens to adjust the position of the optimal focus point within the clear focusing range; according to the position of the optimal focus point, adjust the position and orientation of the imaging device. Parameters such as the height, angle, and orientation of the imaging device can be adjusted through devices such as the pan-tilt head and bracket of the imaging device. During the adjustment, the focusing mode needs to be switched to single-shot autofocus mode, confirm the position of the optimal focus point and make adjustments to ensure that the optimal focus point is within the shooting range and is accurately focused; when the imaging device is accurately focused on the optimal focus point, execute the shooting instruction to take a shot to obtain clear and high-quality photos or videos.

[0092] The effects of the above technical solution are as follows: Through autofocus and fine parameter adjustment, the position of the optimal focus point can be accurately found and focused, thus obtaining clear and high-quality shooting results; the use of autofocus and single-shot autofocus mode can reduce the time and complexity of manual focus adjustment and improve the shooting efficiency; the intelligence and automation of the imaging device can make it easier for users to complete the shooting task and improve the user's shooting experience; this technical solution can be applied to various types of shooting scenarios, such as outdoor, indoor, portrait, landscape, etc., and has wide applicability; through accurate focusing and fine parameter adjustment, high-quality photos or videos can be obtained, improving the shooting quality.

[0093] An embodiment of the present invention is an autofocus system for a TFT-LCD photosensitive array board, and the system includes:

[0094] Light sensing module: The imaging device sends an infrared or ultrasonic signal to an object, and after the infrared or ultrasonic signal is reflected back by the object, it is converted into an electrical signal through the photosensitive elements of the TFT-LCD photosensitive array board.

[0095] Signal Processing Module: The signal processor converts the electrical signal into a digital signal, processes the digital signal, and transmits the processed digital signal to the image processor; the image processor converts the received digital signal into an image and analyzes the image, and the analysis includes edge detection and contrast analysis; and obtains the position of the best focus point according to the analysis result.

[0096] Auto Focus Module: Adjusts the position of the shooting device and takes a shot according to the position of the best focus point.

[0097] The working principle of the above technical solution is as follows: The shooting device sends infrared or ultrasonic signals to the object. After being reflected by the object, these signals will be sensed by the photosensitive element and converted into electrical signals; the photosensitive element converts the sensed optical signal into an electrical signal and transmits it to the signal processor for digital signal processing. In this step, the signal processor can perform operations such as amplifying and filtering the electrical signal to improve the perception ability of the reflected signal; after the digital signal processing is completed, the image processor will convert the received digital signal into an image and analyze the image. Specifically, the image processor will perform operations such as edge detection and contrast analysis to determine the best focusing position; according to the position of the best focus point, the shooting device will automatically adjust the position and perform the shooting operation. By continuously repeating the above steps, the continuous autofocus function for the object can be realized.

[0098] The effects of the above technical solution are as follows: The above technical solution uses a TFT-LCD photosensitive array board to sense light, and through effective image analysis of digital signal processing, the focusing accuracy and speed are improved; this method does not require manual intervention, can avoid errors and time waste caused by manual operation, and improves production efficiency; the above autofocus method can focus quickly and accurately, thereby improving the image quality and allowing users to take clearer and more beautiful photos or videos; the above autofocus method can dynamically adjust calibration parameters according to the real-time feedback signal, so as to adapt to different lighting environments and changes in the characteristics of the photosensitive array board; the above autofocus method can monitor the state of the photosensitive array board at any time, detect and eliminate system faults in time, and ensure the stable and reliable operation of the system.

[0099] An embodiment of the present invention: The light sensing module includes:

[0100] Transmission Module: Sends infrared or ultrasonic signals to the shooting object through the shooting device.

[0101] Reflection Module: The infrared or ultrasonic signal reaches the object surface and is reflected back to become an optical signal and is received by the receiver.

[0102] Receiving Module: The receiver transmits the received optical signal to the TFT-LCD photosensitive array board.

[0103] Sensing module: The photosensitive array board senses the intensity and position of the optical signal; and converts the sensed optical signal into an electrical signal through photosensitive elements.

[0104] The working principle of the above technical solution is as follows: An infrared or ultrasonic signal is sent to the photographed object through a photographing device; when the sent signal reaches the object surface, a part of it is absorbed by the object, and the other part is reflected back by the object surface; after the reflected signal becomes an optical signal, it reaches the photographing device again and is received by the receiver; the receiver transmits the received optical signal to the TFT-LCD photosensitive array board, and the TFT-LCD photosensitive array board senses the intensity and position of the reflected optical signal; and converts the sensed optical signal into an electrical signal through photosensitive elements.

[0105] The effects of the above technical solution are as follows: The autofocus function can greatly improve the shooting efficiency and quality, making the photos clearer and the details more distinct; by utilizing the light-sensing characteristics of the TFT-LCD photosensitive array board, this technology can quickly and accurately complete autofocus adjustment, avoiding the cumbersome and inaccurate manual focusing operation; the above technical solution can work in various environments, including low light, reflection, parallel light and other conditions, and can obtain accurate depth information and the best focusing position; using infrared or ultrasonic signals for distance measurement can avoid errors and blurring phenomena in traditional optical focusing systems, thereby improving the quality and clarity of the photos.

[0106] An embodiment of the present invention: The signal processing module includes:

[0107] Analog-to-digital conversion module: The signal processor converts the electrical signal into a digital signal through an analog-to-digital converter; and processes the digital signal to obtain a digital signal analysis result, and the processing includes filtering, amplification and sampling; the result includes the spectral characteristics, peak value, time domain and frequency domain of the signal;

[0108] Image processing module: Send the processed digital signal to the image processor, and after receiving the digital signal, the image processor processes the digital signal to obtain an image with adjusted brightness, contrast and color balance, an image after denoising processing, and an image after sharpening and blurring processing; the processing includes brightness, contrast and color balance adjustment, noise removal, and sharpening and blurring;

[0109] Feature extraction module: The image processor generates a new digital image according to the processed digital signal, and extracts the features required for the focus point from the new digital image through an edge detection algorithm, and the features include sharpness, contrast and high-frequency signals;

[0110] Among them, the features required for extracting the focus point from the new digital image include converting the color image into a grayscale image; using a smoothing filter, such as a Gaussian filter or a median filter, to reduce noise; using operators such as Sobel, Prewitt, and Roberts to calculate the gradient magnitude and direction at each pixel point; for each pixel point, only retaining the local maximum in its gradient direction and suppressing other local extreme points that are not larger; dividing the pixel points into three categories: strong edges, weak edges, and non-edges according to preset high and low thresholds; and connecting the weak edge pixel points adjacent to the strong edge pixel points to obtain a complete edge.

[0111] Among them, the specific steps for extracting the features required for the focus point from the new digital image are as follows:

[0112] Let the new digital image be L(x, y), and its size be W * B. The clarity Q calculation formula is:

[0113]

[0114] Among them and respectively represent the gray-level steps of the image in the x and y directions;

[0115] The calculation formula for the contrast D is

[0116]

[0117] Among them represents the average gray value of the image;

[0118] The calculation formula for the high-frequency signal G is:

[0119]

[0120] Among them, the ξ 2 represents the Laplacian operator, which can be implemented through the following convolution kernel

[0121]

[0122] Feature matching module: Matching the extracted features with the standard features to find the area in the new digital image that conforms to the standard features; the conforming area is the location of the best focus point;

[0123] Among them, the matching of the extracted features with the standard features is carried out according to the correlation coefficient formula, which is expressed as:

[0124]

[0125] Among them, E T and F trespectively represent the values of the t-th element in the extracted features and the standard features. and respectively represent the means of the extracted features and the standard features. K ∈ (0, 1), and the matching is successful when K > 0.65.

[0126] Information output module: Output the new digital image and the position information of the extracted best focus point.

[0127] The working principle of the above technical solution is as follows: First, the signal processor converts the electrical signal into a digital signal and performs processing such as filtering, amplifying, and sampling on it. Then, the processed digital signal is sent to the image processor through the analog-to-digital converter. The image processor adjusts the brightness, contrast, and color balance, removes noise, and sharpens and blurs it, and generates a new digital image. Next, the image processor uses the edge detection algorithm to extract the features required for the focus point from the new digital image, including sharpness, contrast, and high-frequency signals. Specifically, the algorithm includes the following steps: Convert the color image into a grayscale image; Use a smoothing filter to reduce noise; Calculate the gradient magnitude and direction at each pixel point; For each pixel point, only retain the local maximum in its gradient direction and suppress other non-larger local extreme points; According to the preset high and low thresholds, divide the pixel points into three categories: strong, weak, and non-edge; And use adjacent weak edge pixel points to connect strong edge pixel points to obtain a complete edge. Finally, the image processor matches the extracted features with the standard features to find the area in the new digital image that conforms to the standard features. This area is the position where the best focus point is located. At the same time, output the new digital image and the position information of the extracted best focus point.

[0128] The effects of the above technical solution are as follows: This technical solution can achieve autofocus without the need for manual focus adjustment by the user, improving the accuracy and efficiency of shooting. At the same time, it can also avoid problems such as blurred or out-of-focus photos caused by improper manual focusing, providing a better shooting experience for users. The image processor adjusts the brightness, contrast, and color balance of the digital signal, removes noise, and performs processing such as sharpening and blurring, further improving the quality and clarity of the photo. Through the edge detection algorithm, this technical solution can extract the features required for the focus point in the new digital image, including sharpness, contrast, and high-frequency signals, etc., so as to find the location of the best focus point and improve the accuracy and efficiency of the shooting device. This technical solution is applicable to various types of shooting devices, including mobile phones, cameras, video cameras, etc., and can meet the needs of different users. The above feature point extraction formula can determine the position of the best focus point of the image by calculating features such as the sharpness, contrast, and high-frequency signals of the image. These features can help the autofocus system better understand the content in the image and adjust the focal length of the camera lens to obtain a clear image. At the same time, since the above formula is implemented based on digital image processing technology, it can complete autofocus without human intervention. This enables the camera to quickly adapt to different scenarios and shooting requirements to obtain the best imaging effect. The above formula takes into account multiple focus-related factors (such as sharpness, contrast, and high-frequency signals, etc.), so it can provide very accurate focus results. This enables the camera to better capture the details and contours of the object, thus obtaining a better imaging effect. The above formula is implemented based on digital signal processing technology, so it can operate without being affected by factors such as light and environmental noise. This enables the formula to maintain stable performance under various shooting conditions. At the same time, the above feature matching formula determines the degree of matching by calculating the correlation coefficient between the extracted features and the standard features, and can achieve autofocus more precisely, thereby improving the imaging quality of the camera. At the same time, the above feature matching formula can screen out the extracted features with a higher similarity to the standard features by setting the threshold K>0.65 for successful matching, thereby improving the matching success rate. The calculation speed of the correlation coefficient formula is fast, which can meet the real-time requirements and can quickly complete autofocus during shooting. This matching method is implemented based on a simple correlation coefficient formula and does not require adding other complex algorithms, so it is easy to implement and has strong practicability. An embodiment of the present invention: The autofocus module includes:

[0129] Position adjustment module: The adjustment of the shooting device position and shooting according to the position of the best focus point includes:

[0130] Distance determination module: Determine the distance of the position where the best focus point is located, adjust the focal length of the lens, and adjust the position of the best focus point to the clear focus range;

[0131] Position determination module: According to the position of the best focus point, adjust the position and orientation of the shooting device, and switch the focusing mode to single-shot autofocus mode. Confirm the position of the best focus point and make adjustments; ensure that the best focus point is within the shooting range and is accurately focused; parameters such as the height, angle, and orientation of the camera need to be adjusted.

[0132] Shooting execution module: When the shooting device is accurately focused on the best focus point, execute the shooting instruction to take a shot.

[0133] The working principle of the above technical solution is as follows: According to the edge detection algorithm mentioned above, the clearest part of the image, that is, the position of the best focus point, can be found. According to the ranging function of the camera or other distance measurement tools, determine the distance of the position where the best focus point is located, and adjust the focal length of the lens to adjust the position of the best focus point to the clear focus range; according to the position of the best focus point, adjust the position and orientation of the shooting device. Parameters such as the height, angle, and orientation of the shooting device can be adjusted through devices such as the pan-tilt and bracket of the shooting device. When adjusting, the focusing mode needs to be switched to single-shot autofocus mode, confirm the position of the best focus point and make adjustments to ensure that the best focus point is within the shooting range and is accurately focused; when the shooting device is accurately focused on the best focus point, execute the shooting instruction to take a shot to obtain clear and high-quality photos or videos.

[0134] The effects of the above technical solution are as follows: Through autofocus and fine parameter adjustment, the position of the best focus point can be accurately found and focused, so as to obtain clear and high-quality shooting results; the use of autofocus and single-shot autofocus mode can reduce the time and complexity of manual focus adjustment and improve the shooting efficiency; the intelligence and automation of the shooting device can make it easier for users to complete the shooting task and improve the user's shooting experience; this technical solution can be applied to various types of shooting scenarios, such as outdoor, indoor, portrait, landscape, etc., and has wide applicability; through accurate focusing and fine parameter adjustment, high-quality photos or videos can be obtained, improving the shooting quality.

[0135] An embodiment of the present invention: An electronic device includes a memory, a processor, and a computer program stored on the memory and executable on the memory. The processor executes the program to implement the autofocus method for the TFT-LCD photosensitive array board as described in any one of the above.

[0136] An embodiment of the present invention: A non-transitory computer-readable storage medium stores a computer program thereon, and the program is executed by a processor to implement the autofocus method for the TFT-LCD photosensitive array board as described in any one of the above.

[0137] Obviously, those skilled in the art can make various modifications and variations 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. An autofocus method for a photosensitive array board of a TFT-LCD, characterized in that, The method includes: The photographing device sends an infrared or ultrasonic signal to an object. After the infrared or ultrasonic signal is reflected by the object, it is converted into an electrical signal through a photosensitive element of a TFT-LCD photosensitive array plate. The signal processor converts the electrical signal into a digital signal, processes the digital signal, and transmits the processed digital signal to the image processor. The image processor converts the received digital signal into an image and analyzes the image. The analysis includes edge detection and contrast analysis. And the position of the best focus point is obtained according to the analysis result. According to the position of the best focus point, the position of the photographing device is adjusted and photographing is performed. The signal processor converts the electrical signal into a digital signal, processes the digital signal, and transmits the processed digital signal to the image processor. The image processor converts the received digital signal into an image and analyzes the image. The analysis includes edge detection and contrast analysis. And the position of the best focus point is obtained according to the analysis result. It includes: The signal processor converts the electrical signal into a digital signal through an analog-to-digital converter, and processes the digital signal. The processing includes filtering, amplification, and sampling. The processed digital signal is sent to the image processor. After receiving the digital signal, the image processor processes the digital signal. The processing includes brightness, contrast, and color balance adjustment, noise removal, and sharpening and blurring. The image processor generates a new digital image according to the processed digital signal, and extracts the features required for the focus point from the new digital image through an edge detection algorithm. The features include sharpness, contrast, and high-frequency signals. The extracted features are matched with the standard features to find the area in the new digital image that conforms to the standard features. The conforming area is the position of the best focus point. Wherein, for the matching of the extracted features and the standard features, the matching formula is as follows: Among them, E t and F t respectively represent the values of the t-th element in the extracted feature and the standard feature. and respectively represent the means of the extracted feature and the standard feature. K ∈ (0, 1), and the matching is successful when K > 0.

65. Output the new digital image and the position information of the extracted best focus point.

2. The automatic focusing method for a TFT-LCD photosensitive array plate according to claim 1, characterized in that: The process of the photographing device sending an infrared or ultrasonic signal to an object and converting the infrared or ultrasonic signal into an electrical signal through a photosensitive element of a TFT-LCD photosensitive array plate after being reflected by the object is as follows: Send an infrared or ultrasonic signal to the photographed object through the photographing device. The infrared or ultrasonic signal reaches the object surface, is reflected back to become an optical signal and is received by the receiver. The receiver transmits the received optical signal to the TFT-LCD photosensitive array plate. The photosensitive array plate senses the intensity and position of the optical signal, and converts the sensed optical signal into an electrical signal through the photosensitive element.

3. The automatic focusing method for a TFT-LCD photosensitive array plate according to claim 1, characterized in that: The adjusting the position of the photographing device and performing photographing according to the position of the best focus point includes: Determine the distance of the position where the best focus point is located, adjust the focal length of the lens, and adjust the position of the best focus point to the clear focusing range. Adjust the position and orientation of the imaging device according to the position of the optimal focus point, switch the focusing mode to single-shot autofocus mode, confirm the position of the optimal focus point and make adjustments; When the imaging device is accurately focused on the optimal focus point, execute the shooting instruction to take a picture.

4. An autofocus system for a TFT-LCD photosensitive array board, characterized in that, The system includes: Light sensing module: The imaging device sends an infrared or ultrasonic signal to the object. After the infrared or ultrasonic signal is reflected back by the object, it is converted into an electrical signal by the photosensitive elements of the TFT-LCD photosensitive array board; Signal processing module: The signal processor converts the electrical signal into a digital signal, processes the digital signal, and transmits the processed digital signal to the image processor; the image processor converts the received digital signal into an image and analyzes the image. The analysis includes edge detection and contrast analysis; and obtains the position of the optimal focus point according to the analysis result; Autofocus module: Adjust the position of the imaging device according to the position of the optimal focus point and take a picture; The signal processing module includes: Analog-to-digital conversion module: The signal processor converts the electrical signal into a digital signal through an analog-to-digital converter; and processes the digital signal. The processing includes filtering, amplification, and sampling; Image processing module: Send the processed digital signal to the image processor. After receiving the digital signal, the image processor processes the digital signal. The processing includes brightness, contrast, and color balance adjustment, noise removal, and sharpening and blurring; Feature extraction module: The image processor generates a new digital image according to the processed digital signal, and extracts the features required for the focus point from the new digital image through an edge detection algorithm. The features include sharpness, contrast, and high-frequency signals; Feature matching module: Match the extracted features with the standard features to find the area in the new digital image that conforms to the standard features; the conforming area is the position of the optimal focus point; Among them, the matching of the extracted features with the standard features is carried out according to the following formula: Among them, E t and F t respectively represent the values of the t-th element in the extracted feature and the standard feature. and respectively represent the means of the extracted feature and the standard feature. K ∈ (0, 1), and the matching is successful when K > 0.

65. Information output module: Output the new digital image and the position information of the extracted optimal focus point.

5. The autofocus system for a TFT-LCD photosensitive array board according to claim 4, wherein: The light sensing module includes: Transmission module: Send an infrared or ultrasonic signal to the photographed object through the imaging device; Reflection module: The infrared or ultrasonic signal reaches the object surface and is reflected back to become an optical signal and is received by the receiver; Receiving module: The receiver transmits the received optical signal to the TFT-LCD photosensitive array board; Sensing module: The photosensitive array board senses the intensity and position of the optical signal; and converts the sensed optical signal into an electrical signal through the photosensitive elements.

6. The automatic focusing system for the TFT-LCD photosensitive array board according to claim 4, characterized in that, The autofocus module includes: Position adjustment module: The adjustment of the position of the imaging device according to the position of the optimal focus point and taking a picture includes: Distance determination module: Determine the distance of the position of the optimal focus point, adjust the focal length of the lens, and adjust the position of the optimal focus point to the clear focus range; Position determination module: Adjust the position and orientation of the imaging device according to the position of the optimal focus point, switch the focusing mode to single-shot autofocus mode, confirm the position of the optimal focus point and make adjustments; Shooting execution module: When the shooting device accurately focuses on the best focus point, execute the shooting instruction to take a picture.

7. An electronic device, characterized in that, It includes a memory, a processor, and a computer program stored on and executable on the memory. The processor executes the program to implement the autofocus method for the TFT-LCD photosensitive array board as described in any one of claims 1-3.

8. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by the processor to implement the autofocus method for the TFT-LCD photosensitive array board as described in any one of claims 1-3.

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