Automatic exposure system and method for PCB production

Abstract

The invention relates to the technical field of PCBs, in particular to an automatic exposure system and method for PCB production. Through real-time acquisition and analysis of alignment deviation information, substrate position inclination information and pattern alignment precision of the PCB substrate, possible error sources in the exposure process can be monitored more accurately, and initial parameters of an exposure system are dynamically adjusted through overall exposure deviation, alignment errors and inclination errors. The exposure intensity of the whole exposure area can be effectively balanced, compensation can be performed for different areas by monitoring and adjusting the illumination intensity of a plurality of areas in real time, the exposure time is dynamically adjusted according to the real-time illumination intensity of each area, and the exposure accuracy is improved by obtaining the exposure image in real time and adjusting the illumination intensity. Therefore, each line can be ensured to be formed under proper exposure intensity, and the exposure quality of each area can be analyzed by acquiring the edge degree information of the image in real time.

Description

Technical Field

[0001] The present invention relates to the field of PCB technology, and in particular to an automated exposure system and method for PCB board production. Background Art

[0002] PCB board, also known as printed circuit board, printed circuit board, or printed board for short, is made of insulating board as the base material, cut into a certain size, with at least one conductive pattern attached to it, and arranged with holes (such as component holes, fastening holes, metallized holes, etc.), and realizes the interconnection between electronic components. Since this board is made by electronic printing, it is called a "printed" circuit board.

[0003] Exposure of PCB boards is an important step in the production process of PCB boards. Exposure is to expose the circuit diagram part of the PCB board under the cover of the film base. After exposure, this part undergoes polymerization reaction. Then, during the development process, the unexposed part can be washed away with developer, while the part that undergoes polymerization reaction after exposure cannot be washed away. In this way, the circuit on the PCB board is initially formed. However, in the existing production process of PCB boards, the exposure intensity of PCB boards is often uneven due to inaccurate parameters such as exposure light source and exposure time, which in turn affects the conductivity and aesthetics of the PCB board, thereby affecting the quality of the product. Summary of the invention

[0004] The main purpose of the present invention is to provide an automated exposure method for PCB board production, aiming to solve the technical problems in the prior art.

[0005] The present invention provides a PCB production automated exposure method, comprising:

[0006] Acquire initial alignment feature information of the PCB substrate, wherein the initial alignment feature information includes alignment mark offset information, substrate position tilt information, and pattern alignment accuracy information;

[0007] Acquire an alignment error and a tilt error according to the alignment offset information and the substrate position tilt information;

[0008] Acquire an overall exposure deviation according to the pattern alignment accuracy information, and adjust initial parameters of an exposure system according to the overall exposure deviation, alignment error, and tilt error;

[0009] Acquire multiple regional illumination intensities and real-time exposure images of the adjusted exposure system in real time, and acquire exposure compensation time according to the illumination of the multiple regions;

[0010] Acquire key features of the real-time exposure image, wherein the key features include image edge information and image spatial features;

[0011] Acquiring structural similarity according to the image edge information;

[0012] Acquire a matching degree according to the image space feature, and acquire exposure compensation brightness according to the matching degree and structural similarity;

[0013] The brightness and duration of the exposure system are adjusted according to the exposure compensation brightness and exposure compensation time respectively.

[0014] Preferably, the step of obtaining the alignment error and the tilt error according to the alignment offset information and the substrate position tilt information comprises:

[0015] Acquire a mark horizontal offset, a mark vertical offset and a mark rotation angle offset according to the alignment offset information;

[0016] Acquire a substrate tilt angle, a substrate horizontal offset, and a substrate vertical offset according to the substrate position tilt information;

[0017] Acquire the alignment error according to the mark horizontal offset, the mark vertical offset, the substrate horizontal offset and the substrate vertical offset;

[0018] The tilt error is obtained according to the substrate tilt angle and the mark rotation angle offset.

[0019] Preferably, the step of acquiring the overall exposure deviation according to the pattern alignment accuracy information, and adjusting the parameters of the exposure system according to the overall exposure deviation, the alignment error and the tilt error comprises:

[0020] Acquire a pattern scaling size deviation and a pattern contrast deviation according to the pattern alignment accuracy information;

[0021] Obtaining an overall exposure deviation according to the pattern scaling size deviation and the pattern contrast deviation, and determining whether the overall exposure deviation is greater than a preset exposure deviation;

[0022] If the overall exposure deviation is greater than the preset exposure deviation, the initial exposure compensation of the exposure system is adjusted to decrease;

[0023] If the overall exposure deviation is not greater than the preset exposure deviation, increasing the initial exposure compensation of the exposure system;

[0024] Get the offset direction;

[0025] Acquire a position calibration accuracy according to the offset error and the offset direction, and adjust an initial exposure area of ​​an exposure system according to the position calibration accuracy;

[0026] A focal length error is acquired according to the tilt error, and an initial exposure focal length of an exposure system is adjusted according to the focal length error.

[0027] Preferably, the step of obtaining exposure compensation time according to the illumination of the plurality of areas comprises:

[0028] Acquire total exposure brightness according to the illumination of the plurality of regions;

[0029] Obtaining camera parameters of the exposure system, wherein the camera parameters include aperture value, sensitivity and shutter time;

[0030] Acquire an aperture area according to the aperture value, and acquire an exposure amount according to the aperture area, sensitivity, shutter time, and total exposure brightness;

[0031] Acquire exposure time according to the exposure amount and total exposure brightness;

[0032] A preset exposure duration is obtained, and an exposure compensation time is obtained according to the exposure duration and the preset exposure duration.

[0033] Preferably, the step of obtaining structural similarity according to the image edge information comprises:

[0034] Acquire a plurality of first edge pixel points according to the image edge degree information, and acquire a first red pixel channel value, a first green pixel channel value, and a first blue pixel channel value according to each first edge pixel point;

[0035] Obtaining a first edge pixel average value and a first edge pixel variance value according to a plurality of first red pixel channel values, a plurality of first green pixel channel values, and a plurality of first blue pixel channel values;

[0036] Acquire standard edge degree information of a preset exposure image, and acquire a plurality of second edge pixel points according to the standard edge degree information;

[0037] Acquire a second red pixel channel value, a second green pixel channel value, and a second blue pixel channel value according to each second edge pixel point;

[0038] Acquire a second edge pixel average value and a second edge pixel variance value according to a plurality of second red pixel channel values, a plurality of second green pixel channel values, and a plurality of second blue pixel channel values;

[0039] Obtaining pixel covariance according to the first edge pixel average value and the second edge pixel average value;

[0040] The structural similarity is calculated according to the first edge pixel average value, the first edge pixel variance value, the second edge pixel average value, the second edge pixel variance value and the pixel covariance, wherein the calculation formula is:

[0041]

[0042] Wherein, J(XD) represents structural similarity, X(P1) represents the average value of the first edge pixels, X(P2) represents the average value of the second edge pixels, X(XF) represents pixel covariance, F(C1) represents the variance value of the first edge pixels, and F(C2) represents the variance value of the second edge pixels.

[0043] Preferably, the step of obtaining the matching degree according to the image space feature, and obtaining the exposure compensation brightness according to the matching degree and the structural similarity comprises:

[0044] Acquire pattern intersection area, pattern union area and pattern spacing according to the image space features;

[0045] Obtaining a pattern overlap rate according to the pattern intersection area and the pattern union area;

[0046] The matching degree is calculated according to the pattern overlap rate and the pattern spacing, wherein the calculation formula is:

[0047] P(D) = [1-T(C)]*T(J);

[0048] Among them, P(D) represents the matching degree, T(C) represents the pattern overlap rate, and T(J) represents the pattern spacing;

[0049] Acquire an exposure amount according to the matching degree, and acquire an exposure deviation according to the exposure amount;

[0050] Acquire a local brightness mean value according to the structural similarity, and acquire a brightness difference value according to the local brightness mean value;

[0051] The exposure compensation brightness is acquired according to the brightness difference value and the exposure deviation.

[0052] The present application also provides a PCB board production automated exposure system, comprising:

[0053] A first acquisition module is used to acquire initial alignment feature information of the PCB substrate, wherein the initial alignment feature information includes alignment mark offset information, substrate position tilt information and pattern alignment accuracy information;

[0054] A second acquisition module is used to acquire an alignment error and a tilt error according to the alignment offset information and the substrate position tilt information;

[0055] A first adjustment module, configured to obtain an overall exposure deviation according to the pattern alignment accuracy information, and adjust initial parameters of an exposure system according to the overall exposure deviation, alignment error, and tilt error;

[0056] A third acquisition module is used to acquire in real time the illumination intensity and real-time exposure image of multiple regions of the adjusted exposure system, and acquire exposure compensation time according to the illumination of the multiple regions;

[0057] A fourth acquisition module, used to acquire key features of the real-time exposure image, wherein the key features include image edge information and image space features;

[0058] A fifth acquisition module, used for acquiring structural similarity according to the image edge information;

[0059] A sixth acquisition module, used to acquire a matching degree according to the image space feature, and acquire an exposure compensation brightness according to the matching degree and the structural similarity;

[0060] The second adjustment module is used to adjust the brightness and duration of the exposure system according to the exposure compensation brightness and exposure compensation time respectively.

[0061] Preferably, the second acquisition module includes:

[0062] A first acquisition unit, configured to acquire a mark horizontal offset, a mark vertical offset, and a mark rotation angle offset according to the alignment offset information;

[0063] A second acquisition unit is used to acquire a substrate tilt angle, a substrate horizontal offset, and a substrate vertical offset according to the substrate position tilt information;

[0064] A third acquisition unit is used to acquire the alignment error according to the mark horizontal offset, the mark vertical offset, the substrate horizontal offset and the substrate vertical offset;

[0065] The fourth acquisition unit is used to acquire the tilt error according to the substrate tilt angle and the mark rotation angle offset.

[0066] The present invention also provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the above-mentioned PCB board production automated exposure method when executing the computer program.

[0067] The present invention also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned PCB board production automated exposure method are implemented.

[0068] The beneficial effects of the present invention are as follows: by real-time acquisition and analysis of the alignment offset information, substrate position tilt information and pattern alignment accuracy of the PCB substrate, the present invention can more accurately monitor possible sources of errors in the exposure process; by dynamically adjusting the initial parameters of the exposure system through the overall exposure deviation, alignment error and tilt error, the exposure intensity of the entire exposure area can be effectively balanced; by real-time monitoring and adjusting the illumination intensity of multiple areas, compensation can be performed for different areas; according to the real-time illumination intensity of each area, the exposure time can be dynamically adjusted; by real-time acquisition of the exposure image and adjustment of the illumination intensity, each circuit can be ensured to be formed under an appropriate exposure intensity; by real-time monitoring of the illumination intensity of each area, the non-uniformity of illumination can be found and compensated in real time; by real-time acquisition of the edge information of the image, the exposure quality of each area can be analyzed; by calculating the structural similarity, the local feature difference of the image can be evaluated; by real-time monitoring of the edge, structural similarity and spatial features of the exposure image, not only the manual intervention is reduced, but also the stability and accuracy of the exposure process are greatly improved; by automatically analyzing the edge and spatial features in the exposure image, the exposure compensation brightness and exposure time can be intelligently adjusted. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Figure 1 The figure is a schematic diagram of a method flow according to an embodiment of the present invention.

[0070] Figure 2 FIG. 1 is a schematic diagram of a device structure according to an embodiment of the present invention.

[0071] Figure 3 A schematic diagram of the internal structure of a computer device according to an embodiment of the present application.

[0072] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0073] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0074] like Figure 1 - Figure 3 As shown, the present application provides a PCB board production automated exposure method, comprising:

[0075] S1. Acquire initial alignment feature information of a PCB substrate, wherein the initial alignment feature information includes alignment mark offset information, substrate position tilt information, and pattern alignment accuracy information;

[0076] S2. Acquire an alignment error and a tilt error according to the alignment offset information and the substrate position tilt information;

[0077] S3, obtaining an overall exposure deviation according to the pattern alignment accuracy information, and adjusting initial parameters of the exposure system according to the overall exposure deviation, alignment error and tilt error;

[0078] S4, obtaining in real time the illumination intensity and real-time exposure images of multiple regions of the adjusted exposure system, and obtaining exposure compensation time according to the illumination of the multiple regions;

[0079] S5. Acquire key features of the real-time exposure image, wherein the key features include image edge information and image space features;

[0080] S6, obtaining structural similarity according to the image edge information;

[0081] S7, obtaining a matching degree according to the image space feature, and obtaining an exposure compensation brightness according to the matching degree and the structural similarity;

[0082] S8. Adjust the brightness and duration of the exposure system according to the exposure compensation brightness and exposure compensation time.

[0083] As described in the above steps S1-S8, PCB board, also known as printed circuit board, printed circuit board, is cut into a certain size with an insulating board as a substrate, with at least one conductive pattern attached thereon, and is provided with holes (such as component holes, fastening holes, metallized holes, etc.), and realizes the mutual connection between electronic components. Since this board is made by electronic printing, it is called "printed" circuit board. The exposure of PCB board is an important step in the production process of PCB board. Exposure means that the PCB board is exposed to the circuit diagram part under the shielding of the film base plate, and polymerization reaction occurs in this part after exposure, and then in the developing process, the unexposed part can be washed out with developer, and the part where polymerization reaction occurs after exposure cannot be washed out, so that the circuit on the PCB board is initially formed. But in the production process of existing PCB board, PCB board often causes uneven exposure intensity due to inaccurate parameters such as exposure light source and exposure time, thereby affecting the conductivity and aesthetics of PCB board, thereby affecting the quality of product. The present invention obtains the alignment error and the tilt error through the alignment offset information and the substrate position tilt information of the PCB substrate, and then obtains the overall exposure deviation according to the pattern alignment accuracy information of the PCB substrate, and adjusts the initial parameters of the exposure system according to the overall exposure deviation, the alignment error and the tilt error, wherein the alignment mark offset information refers to the deviation between the actual alignment mark position on the substrate and the designed predetermined position during the exposure process, the substrate position tilt refers to the existence of a certain tilt angle of the PCB substrate relative to the ideal plane of the lithography equipment during the exposure process, and the pattern alignment accuracy refers to the alignment accuracy between the exposure pattern and the existing pattern or graphic on the substrate during the exposure process. By real-time acquisition and analysis of the alignment offset information, the substrate position tilt information and the pattern alignment accuracy of the PCB substrate, the possible error sources in the exposure process can be monitored more accurately, and the alignment error and the tilt error can be corrected through a feedback mechanism, thereby effectively Reduce the exposure error caused by inaccurate substrate alignment or tilt during the exposure process. Uneven exposure intensity is a major factor leading to PCB board quality problems. By dynamically adjusting the initial parameters of the exposure system according to the overall exposure deviation, alignment error and tilt error, the exposure intensity of the entire exposure area can be effectively balanced, and the phenomenon of local over-exposure or over-weak exposure can be reduced, thereby ensuring the exposure uniformity of the entire PCB board, allowing the exposure system to be more intelligently adaptively adjusted, which not only reduces the complexity and errors of manual operations, but also improves the automation level of the production line, improves production efficiency and consistency, and obtains the illumination intensity and real-time exposure images of multiple areas of the adjusted exposure system in real time, and obtains the exposure compensation time according to the illumination of multiple areas. It can effectively solve the problem of uneven exposure intensity caused by inaccurate parameters such as exposure light source and exposure time in the prior art, thereby significantly improving the conductivity and aesthetics of the PCB board.Specifically, the intensity of the exposure light source may vary across the entire exposure area, resulting in overexposure or underexposure in some areas, which in turn affects the quality of the PCB pattern. Therefore, by real-time monitoring and adjusting the light intensity of multiple areas, compensation can be made for different areas to ensure that each area receives relatively uniform light. By dynamically adjusting the exposure time according to the real-time light intensity of each area, the problem of local overexposure or underexposure caused by uneven exposure time can be effectively avoided. This ensures that the overall exposure is consistent and avoids the negative impact of light intensity differences on PCB quality. Uneven exposure may cause overexposed areas on the circuit board, and the patterns in these areas may be incomplete or inaccurate, resulting in circuit short circuits or open circuits. By acquiring exposure images in real time and adjusting the light intensity, the occurrence of such defects can be reduced to ensure that each circuit is formed at the appropriate exposure intensity. During the exposure process, by real-time monitoring of the light intensity of each area, the unevenness of the light can be discovered and compensated in real time.For example, if the light intensity in a certain area is low, the exposure time of the area can be increased, or the intensity of the light source can be adjusted to compensate for it, so as to avoid local underexposure caused by uneven light intensity. According to the real-time light intensity feedback, the required exposure compensation time can be automatically calculated. This compensation mechanism can ensure that the exposure of all areas is relatively consistent during the entire exposure process, avoiding uneven exposure caused by human errors or equipment errors. Then, the structural similarity is obtained based on the image edge information in the key features of the real-time exposure image, and the matching degree is obtained based on the image spatial features. The exposure compensation brightness is obtained based on the matching degree and structural similarity. The brightness and duration of the exposure system are adjusted according to the exposure compensation brightness and exposure compensation time. By obtaining the edge information of the image in real time, the exposure quality of each area can be analyzed, and areas with uneven exposure or uneven light intensity distribution can be identified. The calculation of structural similarity can evaluate the local feature differences of the image and identify which areas have not been exposed as expected. Through the calculation of spatial feature matching, further Understand the exposure conditions of different areas, especially complex patterns or detail areas, ensure that the exposure of these areas is accurately adjusted to avoid local overexposure or underexposure. According to the matching degree and structural similarity, automatically calculate and adjust the compensation brightness and exposure time of the exposure system, so that the exposure is more balanced in each area, avoid the deviation of exposure intensity, and thus improve the exposure uniformity of the entire PCB board. In the traditional PCB exposure process, the exposure time and light intensity are often adjusted manually or with preset parameters, but these methods cannot cope with complex situations. By real-time monitoring of the edge degree, structural similarity and spatial characteristics of the exposure image, the exposure parameters are automatically calculated and adjusted, which not only reduces manual intervention, but also greatly improves the stability and accuracy of the exposure process. By automatically analyzing the edge and spatial characteristics in the exposure image, the exposure compensation brightness and exposure time can be intelligently adjusted. This adaptive adjustment mechanism enables the exposure system to make feedback based on real-time image characteristics and matching degree, improve the intelligence level of the system, and reduce human errors.

[0084] In one embodiment, the step S2 of acquiring the alignment error and the tilt error according to the alignment offset information and the substrate position tilt information comprises:

[0085] S21, acquiring a mark horizontal offset, a mark vertical offset, and a mark rotation angle offset according to the alignment offset information;

[0086] S22, acquiring a substrate tilt angle, a substrate horizontal offset, and a substrate vertical offset according to the substrate position tilt information;

[0087] S23, obtaining a positioning error according to the mark horizontal offset, the mark vertical offset, the substrate horizontal offset and the substrate vertical offset;

[0088] S24, obtaining a tilt error according to the substrate tilt angle and the mark rotation angle offset.

[0089] As described in the above steps S21-S24, the present invention obtains the mark horizontal offset, the mark vertical offset and the mark rotation angle offset through the alignment offset information, obtains the substrate tilt angle, the substrate horizontal offset and the substrate vertical offset through the substrate position tilt information, and then obtains the alignment error according to the mark horizontal offset, the mark vertical offset, the substrate horizontal offset and the substrate vertical offset, and obtains the tilt error according to the substrate tilt angle and the mark rotation angle offset. By obtaining the horizontal and vertical offsets of the mark and the horizontal and vertical offsets of the substrate, the alignment error can be accurately calculated, which makes it possible to accurately align the photolithography pattern and the substrate position during the exposure process, ensure that the light source irradiates the correct area, reduce the photolithography defects caused by the exposure alignment error, and thus improve the accuracy of the PCB circuit pattern. The rotation offset between the substrate and the mark (calculated by the mark rotation angle offset) can be compensated, thereby avoiding the exposure error caused by the rotation or tilt of the substrate. Since the tilt angle of the substrate has a great influence on the exposure quality, if the substrate tilts during the exposure process, the irradiation angle of the light source will change, resulting in uneven exposure intensity, affecting the quality and appearance of the circuit. By measuring and compensating the substrate tilt angle, the uneven exposure caused by the tilt can be effectively avoided, thereby ensuring that the entire PCB surface obtains uniform exposure intensity. The compensation of the alignment error and tilt error makes the light source irradiation more consistent during the exposure process, which can avoid local underexposure or overexposure, ensure the uniform exposure quality of the PCB, and further improve the reliability of the circuit. Uneven exposure often leads to color difference, blur or pattern distortion, affecting the appearance of the PCB. By accurately controlling the alignment and tilt compensation during the exposure process, the clarity, sharpness and symmetry of the lithography pattern can be ensured, avoiding aesthetic problems caused by uneven exposure. This method can monitor and adjust the alignment error, tilt error and rotation error during the exposure process in real time through the automation system, which not only reduces the error of human operation, but also improves the intelligence and adaptability of the system. The system can automatically adjust according to real-time data, reducing the interference of human factors in the production process. Real-time feedback and adjustment can enable the system to automatically optimize the exposure conditions according to the actual situation of each production batch, ensuring that the exposure quality of each PCB meets the standard, and improving production flexibility and intelligence.

[0090] In one embodiment, the step S3 of acquiring the overall exposure deviation according to the pattern alignment accuracy information, and adjusting the parameters of the exposure system according to the overall exposure deviation, the alignment error and the tilt error includes:

[0091] S31, acquiring a pattern scaling size deviation and a pattern contrast deviation according to the pattern alignment accuracy information;

[0092] S32, obtaining an overall exposure deviation according to the pattern scaling size deviation and the pattern contrast deviation, and determining whether the overall exposure deviation is greater than a preset exposure deviation;

[0093] If the overall exposure deviation is greater than the preset exposure deviation, the initial exposure compensation of the exposure system is adjusted to decrease;

[0094] If the overall exposure deviation is not greater than the preset exposure deviation, increasing the initial exposure compensation of the exposure system;

[0095] S33, obtaining the offset direction;

[0096] S34, acquiring a position calibration accuracy according to the offset error and the offset direction, and adjusting an initial exposure area of ​​an exposure system according to the position calibration accuracy;

[0097] S35. Obtain a focal length error according to the tilt error, and adjust an initial exposure focal length of an exposure system according to the focal length error.

[0098] As described in the above steps S31-S35, the present invention obtains the pattern scaling size deviation and the pattern contrast deviation through the pattern alignment accuracy information, and obtains the overall exposure deviation according to the pattern scaling size deviation and the pattern contrast deviation. By judging whether the overall exposure deviation is greater than the preset exposure deviation, if it is greater, the initial exposure compensation of the exposure system is reduced, otherwise, the initial exposure compensation of the exposure system is increased. By obtaining the pattern scaling size deviation and the pattern contrast deviation, the deviation of the pattern during the exposure process can be accurately evaluated, thereby optimizing the compensation of the exposure system. If it is found that the exposure intensity is uneven, the exposure compensation is automatically adjusted to improve the exposure uniformity. In this way, the conductivity difference or aesthetic problem of the PCB board caused by uneven exposure can be avoided, thereby ensuring the quality of the entire circuit board. By judging whether the overall exposure deviation exceeds the threshold of the preset exposure deviation, the compensation of the exposure system is automatically adjusted, and the automated compensation process reduces manual intervention. The requirements of the production process are met, and the problems of inaccurate manual operation or missed adjustments are reduced, thereby improving the stability and consistency of the production process. Through real-time monitoring and adjustment of exposure compensation, the exposure system can be continuously optimized during each production process to reduce the impact of factors such as exposure light source intensity fluctuations and inaccurate exposure time on imaging quality. The position calibration accuracy is obtained through the offset error and the offset direction, and the initial exposure area of ​​the exposure system is adjusted according to the position calibration accuracy. The focal length error is obtained through the tilt error, and the initial exposure focal length of the exposure system is adjusted according to the focal length error. By adjusting the initial exposure area of ​​the exposure system according to the offset error and the offset direction, the uniformity of the exposure intensity in the entire exposure area can be effectively guaranteed to avoid overexposure or underexposure, so that the final circuit pattern is more accurate and has consistent conductivity. The focal length error may cause the resolution of the photolithography pattern to decrease, and even unclear focus or pattern misalignment may occur. By obtaining the focal length error based on the tilt error and adjusting the initial exposure focal length of the exposure system, it is possible to effectively ensure that the focus during lithography is always kept at the optimal position. This not only improves the fineness of the pattern, but also prevents pattern blur or error accumulation due to inaccurate focal length, thereby improving the reliability and quality of the PCB. This allows precise control of various parameters of the exposure system to ensure uniform light intensity and accurate focal length during the exposure process, thereby improving the quality and production efficiency of the PCB board and reducing conductivity and aesthetic problems caused by inaccurate exposure. This optimization method not only improves the stability and consistency of the product, but also helps to reduce production costs and improve the automation and intelligence level of the production line.

[0099] In one embodiment, the step S4 of acquiring the exposure compensation time according to the illumination of the plurality of regions comprises:

[0100] S41, obtaining total exposure brightness according to the illumination of the multiple regions;

[0101] S42, obtaining camera parameters of the exposure system, wherein the camera parameters include aperture value, sensitivity and shutter time;

[0102] S43, obtaining the aperture area according to the aperture value, and calculating the exposure according to the aperture area, sensitivity, shutter time and total exposure brightness, the calculation formula is: Among them, B(GL) represents the exposure, B(ZL) represents the total exposure brightness, G(GD) represents the sensitivity, G(QM) represents the aperture area, and K(MS) represents the shutter time;

[0103] S44, calculating the exposure time according to the exposure amount and the total exposure brightness, wherein the calculation formula is: Among them, B(SC) represents the exposure duration, B(GL) represents the exposure amount, and B(ZL) represents the total exposure brightness;

[0104] S45: Obtain a preset exposure duration, and calculate an exposure compensation time according to the sum of the exposure duration and the preset exposure duration.

[0105] As described in the above steps S41-S45, the present invention obtains the total exposure brightness through multiple regional illumination, and then obtains the aperture area according to the aperture value in the camera parameters of the exposure system, and obtains the exposure amount according to the aperture area, sensitivity, shutter time and total exposure brightness, and obtains the exposure time according to the exposure amount and the total exposure brightness, and obtains the preset exposure time, and obtains the exposure compensation time according to the exposure time and the preset exposure time, and obtains the illumination of multiple regions and calculates the total exposure brightness, so that the illumination intensity of the entire exposure area can be measured in detail, which enables the exposure system to better grasp the illumination distribution, thereby avoiding the problems of uneven light source, local overexposure or underexposure that may occur in the traditional exposure process. This precise exposure intensity control helps to ensure the clarity and uniformity of the PCB pattern, and ensure the conductivity and integrity of the circuit. The exposure is calculated by calculating the aperture area, sensitivity, shutter time and total exposure brightness, and then the exposure is calculated. Finally, the exposure time is calculated according to the exposure and the total exposure brightness. On this basis, the exposure compensation time is obtained by calibration according to the preset exposure time. This enables the exposure system to automatically adjust the exposure time and compensation time to eliminate the deviation caused by the fluctuation of the exposure light source and the change of equipment performance. The automatic adjustment can reduce manual intervention, reduce human errors, and improve the consistency and reliability of the exposure process. By accurately controlling the exposure time and light intensity, it can ensure that each area on the PCB is properly exposed, thereby effectively avoiding electrical defects caused by uneven light sources or inaccurate exposure time. Traditional exposure technology may cause some areas to be overexposed or too weak due to unstable light sources or inaccurate focusing. The present invention calculates according to parameters such as total exposure brightness and aperture area. The system can dynamically adjust the exposure and exposure time before each exposure to ensure that the distribution of light in different areas is more uniform and avoid local overexposure or underexposure.

[0106] In one embodiment, the step S6 of acquiring the structural similarity according to the image edge information includes:

[0107] S61, acquiring a plurality of first edge pixel points according to the image edge degree information, and acquiring a first red pixel channel value, a first green pixel channel value, and a first blue pixel channel value according to each first edge pixel point;

[0108] S62, obtaining a first edge pixel average value and a first edge pixel variance value according to a plurality of first red pixel channel values, a plurality of first green pixel channel values, and a plurality of first blue pixel channel values;

[0109] S63, obtaining standard edge degree information of a preset exposure image, and obtaining a plurality of second edge pixel points according to the standard edge degree information;

[0110] S64, acquiring a second red pixel channel value, a second green pixel channel value, and a second blue pixel channel value according to each second edge pixel point;

[0111] S65, obtaining a second edge pixel average value and a second edge pixel variance value according to a plurality of second red pixel channel values, a plurality of second green pixel channel values, and a plurality of second blue pixel channel values;

[0112] S66, obtaining pixel covariance according to the first edge pixel average value and the second edge pixel average value;

[0113] S67, calculating structural similarity according to the first edge pixel average value, the first edge pixel variance value, the second edge pixel average value, the second edge pixel variance value and the pixel covariance, wherein the calculation formula is:

[0114]

[0115] Wherein, J(XD) represents structural similarity, X(P1) represents the average value of the first edge pixels, X(P2) represents the average value of the second edge pixels, X(XF) represents pixel covariance, F(C1) represents the variance value of the first edge pixels, and F(C2) represents the variance value of the second edge pixels.

[0116] As described in the above steps S61-S67, the present invention obtains multiple first edge pixel points through image edge degree information, and obtains a first red pixel channel value, a first green pixel channel value and a first blue pixel channel value according to each first edge pixel point, obtains a first edge pixel average value and a first edge pixel variance value through the multiple first red pixel channel values, multiple first green pixel channel values ​​and multiple first blue pixel channel values, obtains standard edge degree information of a preset exposure image, and obtains multiple second edge pixel points according to the standard edge degree information, obtains a second red pixel channel value, a second green pixel channel value and a second blue pixel channel value through each second edge pixel point, and obtains a second edge pixel average value and a second edge pixel variance value through the multiple second red pixel channel values, multiple second green pixel channel values ​​and multiple second blue pixel channel values. In PCB manufacturing, the uniformity of the exposure light source is very important. If the light source is uneven, the exposure intensity in some areas may be too strong or too weak, resulting in blurred or distorted patterns, thereby affecting conductivity and aesthetics. By analyzing the edge information of the image, the lighting conditions of the edge pixels can be accurately located, and then the uniformity of exposure can be analyzed based on the color values ​​of the red, green, and blue channels. The mean and variance values ​​provide an accurate measure of the regional exposure intensity distribution, which can help identify uneven parts during the exposure process. By calculating the RGB channel values ​​of each edge pixel and obtaining the mean and variance values ​​of these pixels, the color changes of the exposed area can be quantified, thereby revealing deviations in the exposure process. For example, if an area is overexposed, it may cause the color values ​​of the RGB channels to be abnormally high; if it is underexposed, the RGB values ​​may be low.The variance value of edge pixels can effectively reflect the fluctuation of exposure intensity in different areas, thereby helping to accurately identify and adjust the problem of uneven exposure. By carefully analyzing the pixels at the edge of the image, the instability of the light source (such as brightness changes) can be quickly identified. The variance of edge pixels reflects the changes in local exposure. If the variance is large, it indicates that the instability of the light source is high, which may lead to uneven exposure. By analyzing the edge pixels of the exposure area, it can ensure that the transition of each edge is smooth and clear, which is especially important for high-precision circuit boards. By calculating the mean and variance of edge pixels, the blur or error of pattern details in exposure can be detected, thereby adjusting the exposure parameters to ensure the accuracy of the circuit pattern on the circuit board and reduce electrical defects (such as short circuits or open circuits). The pixel covariance is obtained through the first edge pixel average value and the second edge pixel average value. The structural similarity is calculated by the average value of the second edge pixels, the variance value of the second edge pixels and the pixel covariance. Pixel covariance is an important indicator to measure the relationship between two groups of pixels (such as the first edge and the second edge pixels). It can help identify the correlation between the parts in the exposed image. By calculating the covariance of the exposure area, the similarity and consistency of the exposure intensity in different areas can be judged, thereby revealing the areas of uneven exposure. The calculation of structural similarity is based on the average value and variance value of the edge pixels. It can effectively evaluate the lighting differences in different areas of the exposed image. This evaluation method can not only help identify the problem of uneven intensity during the exposure process, but also accurately locate the specific areas of uneven exposure, and then optimize the overall exposure uniformity by adjusting the exposure parameters (such as exposure time and light source intensity). During the exposure process, changes in light source intensity and exposure time may cause over- or under-exposure of certain areas, resulting in pattern distortion and conductivity differences. By calculating the structural similarity and pixel covariance, the exposure deviation generated during the exposure process can be monitored in real time, and problems such as uneven light source and improper exposure time can be discovered in time. By adjusting the exposure parameters (such as light source brightness, exposure time, etc.) for compensation, the pattern on the PCB board can be ensured to be clear and the lighting is uniform, thereby avoiding circuit performance fluctuations caused by uneven exposure. The mean, variance and covariance of edge pixels can be automatically calculated based on image analysis, which can automate the quality control process, help optimize the exposure process, improve exposure uniformity, thereby ensuring the conductivity, appearance quality and electrical performance of the PCB, reducing deviations in the production process, reducing scrap rates, improving production efficiency, and ensuring the consistency and high quality of the final product.

[0117] In one embodiment, the step S7 of acquiring the matching degree according to the image spatial features and acquiring the exposure compensation brightness according to the matching degree and the structural similarity includes:

[0118] S71, acquiring a pattern intersection area, a pattern union area and a pattern spacing according to the image space feature;

[0119] S72, obtaining a pattern overlap rate according to the pattern intersection area and the pattern union area;

[0120] S73, calculating the matching degree according to the pattern overlap rate and the pattern spacing, wherein the calculation formula is:

[0121] P(D) = [1-T(C)]*T(J);

[0122] Among them, P(D) represents the matching degree, T(C) represents the pattern overlap rate, and T(J) represents the pattern spacing;

[0123] S74, obtaining an exposure amount according to the matching degree, and obtaining an exposure deviation according to the exposure amount;

[0124] S75, obtaining a local brightness mean value according to the structural similarity, and obtaining a brightness difference value according to the local brightness mean value;

[0125] S76. Obtain exposure compensation brightness according to the brightness difference value and the exposure deviation.

[0126] As described in the above steps S71-S76, the present invention obtains the pattern intersection area, the pattern union area and the pattern spacing through image space features, and obtains the pattern overlap rate according to the pattern intersection area and the pattern union area, and calculates the matching degree through the pattern overlap rate and the pattern spacing, wherein the pattern overlap rate refers to the matching of the same or similar patterns in two images, and the pattern spacing refers to the spatial distance between adjacent patterns in the image. The calculation of the pattern intersection area and the pattern union area can help quantify the overlap and distribution of patterns during PCB exposure and evaluate the impact of uneven exposure on pattern morphology. When the exposure light source is uneven, some areas may be overexposed or underexposed, resulting in changes in the intersection or spacing between patterns. By calculating this Some geometric features can accurately identify pattern changes caused by uneven exposure, such as excessive pattern overlap or unnecessary increase in spacing. The pattern overlap rate is a key indicator that reflects whether there is abnormal overlap between different patterns, which is usually caused by uneven exposure. If the overlap rate is too high, it may indicate that a certain area is overexposed, resulting in blurred patterns. If the overlap rate is too low, it may indicate insufficient exposure and the pattern is not fully displayed. During the exposure process, by adjusting the exposure parameters (such as exposure time, light source intensity, etc.), according to the calculated overlap rate and matching degree, the shape and size of the circuit pattern can be more accurately controlled to ensure that the conductivity of each area on the PCB meets the design requirements and reduce the generation of unqualified areas. The pattern spacing is The electrical performance of PCB is very important. Too small pattern spacing may cause signal interference, electrical short circuit or poor contact. By calculating the pattern spacing and matching degree, the rationality of pattern spacing in different areas can be accurately evaluated. By analyzing the relationship between pattern spacing and exposure uniformity, it helps to adjust the light source intensity or exposure time during the exposure process to ensure the uniformity of pattern spacing on the entire PCB, thereby improving electrical performance. By evaluating the matching degree of the pattern, the exposure parameters can be better adjusted to reduce problems such as blurred patterns and unclear contours caused by uneven exposure, thereby ensuring the aesthetics of the PCB board. The exposure amount is obtained through the matching degree, and the exposure deviation is obtained based on the exposure amount. The local brightness mean is obtained through structural similarity, and the local The brightness mean value obtains the brightness difference value, and then the exposure compensation brightness is calculated according to the sum of the brightness difference value and the exposure deviation. Among them, the exposure deviation reflects the difference between the exposure value and the ideal exposure value of the image, which is usually used to indicate the difference in exposure level in image processing or camera settings. The brightness difference value usually refers to the difference in overall brightness between the current image and the target image (such as the ideal exposure image or the reference image). By accurately measuring and compensating for the exposure and local brightness differences, the impact of uneven exposure light source or inaccurate exposure time can be effectively reduced, thereby ensuring that the exposure intensity of each area on the PCB board is more uniform. During the exposure process, factors such as unstable light source and fluctuation of exposure time may lead to fluctuations in product quality.By calculating and compensating for exposure deviations, the stability of the photolithography process can be further improved, ensuring that the exposure effect of PCB products remains consistent in different batches of production, thereby improving the controllability and reliability of the production process. This allows for more accurate control of the light intensity distribution during PCB exposure and reduces various problems caused by uneven exposure. This can not only improve the conductivity and appearance quality of the PCB, but also optimize the production process, improve production efficiency and product consistency.

[0127] The present application also provides a PCB board production automated exposure system, comprising:

[0128] A first acquisition module is used to acquire initial alignment feature information of the PCB substrate, wherein the initial alignment feature information includes alignment mark offset information, substrate position tilt information and pattern alignment accuracy information;

[0129] A second acquisition module is used to acquire an alignment error and a tilt error according to the alignment offset information and the substrate position tilt information;

[0130] A first adjustment module, configured to obtain an overall exposure deviation according to the pattern alignment accuracy information, and adjust initial parameters of an exposure system according to the overall exposure deviation, alignment error, and tilt error;

[0131] A third acquisition module is used to acquire in real time the illumination intensity and real-time exposure image of multiple regions of the adjusted exposure system, and acquire exposure compensation time according to the illumination of the multiple regions;

[0132] A fourth acquisition module, used to acquire key features of the real-time exposure image, wherein the key features include image edge information and image space features;

[0133] A fifth acquisition module, used for acquiring structural similarity according to the image edge information;

[0134] A sixth acquisition module, used to acquire a matching degree according to the image space feature, and acquire an exposure compensation brightness according to the matching degree and the structural similarity;

[0135] The second adjustment module is used to adjust the brightness and duration of the exposure system according to the exposure compensation brightness and exposure compensation time respectively.

[0136] In one embodiment, the second acquisition module includes:

[0137] A first acquisition unit, configured to acquire a mark horizontal offset, a mark vertical offset, and a mark rotation angle offset according to the alignment offset information;

[0138] A second acquisition unit is used to acquire a substrate tilt angle, a substrate horizontal offset, and a substrate vertical offset according to the substrate position tilt information;

[0139] A third acquisition unit, configured to acquire an alignment error according to the mark horizontal offset, the mark vertical offset, the substrate horizontal offset, and the substrate vertical offset;

[0140] The fourth acquisition unit is used to acquire the tilt error according to the substrate tilt angle and the mark rotation angle offset.

[0141] The present invention also provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the above-mentioned PCB board production automated exposure method when executing the computer program.

[0142] The present invention also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned PCB board production automated exposure method are implemented.

[0143] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing related hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media provided in this application and used in the embodiments may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (SSRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0144] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, device, article or method including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, device, article or method. In the absence of further restrictions, an element defined by the sentence "includes a ..." does not exclude the presence of other identical elements in the process, device, article or method including the element.

[0145] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A PCB production automated exposure method, characterized in that: Applied to exposure systems, including: Acquire initial alignment feature information of the PCB substrate, wherein the initial alignment feature information includes alignment mark offset information, substrate position tilt information, and pattern alignment accuracy information; Acquire an alignment error and a tilt error according to the alignment offset information and the substrate position tilt information; Acquire an overall exposure deviation according to the pattern alignment accuracy information, and adjust initial parameters of an exposure system according to the overall exposure deviation, alignment error, and tilt error; Acquire multiple regional illumination intensities and real-time exposure images of the adjusted exposure system in real time, and acquire exposure compensation time according to the illumination of the multiple regions; Acquire key features of the real-time exposure image, wherein the key features include image edge information and image spatial features; Acquiring structural similarity according to the image edge information; Acquire a matching degree according to the image space feature, and acquire exposure compensation brightness according to the matching degree and structural similarity; The brightness and duration of the exposure system are adjusted according to the exposure compensation brightness and exposure compensation time respectively.

2. The PCB production automated exposure method according to claim 1, characterized in that: The step of obtaining the alignment error and the tilt error according to the alignment offset information and the substrate position tilt information comprises: Acquire a mark horizontal offset, a mark vertical offset and a mark rotation angle offset according to the alignment offset information; Acquire a substrate tilt angle, a substrate horizontal offset, and a substrate vertical offset according to the substrate position tilt information; Acquire the alignment error according to the mark horizontal offset, the mark vertical offset, the substrate horizontal offset and the substrate vertical offset; The tilt error is obtained according to the substrate tilt angle and the mark rotation angle offset.

3. The PCB production automated exposure method according to claim 1, characterized in that: The step of acquiring the overall exposure deviation according to the pattern alignment accuracy information, and adjusting the parameters of the exposure system according to the overall exposure deviation, the alignment error and the tilt error comprises: Acquire a pattern scaling size deviation and a pattern contrast deviation according to the pattern alignment accuracy information; Obtaining an overall exposure deviation according to the pattern scaling size deviation and the pattern contrast deviation, and determining whether the overall exposure deviation is greater than a preset exposure deviation; If the overall exposure deviation is greater than the preset exposure deviation, the initial exposure compensation of the exposure system is adjusted to decrease; If the overall exposure deviation is not greater than the preset exposure deviation, increasing the initial exposure compensation of the exposure system; Get the offset direction; Acquire a position calibration accuracy according to the offset error and the offset direction, and adjust an initial exposure area of ​​an exposure system according to the position calibration accuracy; A focal length error is acquired according to the tilt error, and an initial exposure focal length of an exposure system is adjusted according to the focal length error.

4. The PCB production automated exposure method according to claim 1, characterized in that: The step of obtaining exposure compensation time according to the illumination of the plurality of areas comprises: Acquire total exposure brightness according to the illumination of the plurality of regions; Obtaining camera parameters of the exposure system, wherein the camera parameters include aperture value, sensitivity and shutter time; Acquire an aperture area according to the aperture value, and acquire an exposure amount according to the aperture area, sensitivity, shutter time, and total exposure brightness; Acquire exposure time according to the exposure amount and total exposure brightness; A preset exposure duration is obtained, and an exposure compensation time is obtained according to the exposure duration and the preset exposure duration.

5. The PCB production automated exposure method according to claim 1, characterized in that: The step of obtaining structural similarity according to the image edge information comprises: Acquire a plurality of first edge pixel points according to the image edge degree information, and acquire a first red pixel channel value, a first green pixel channel value, and a first blue pixel channel value according to each first edge pixel point; Obtain a first edge pixel average value and a first edge pixel variance value according to a plurality of first red pixel channel values, a plurality of first green pixel channel values, and a plurality of first blue pixel channel values; Acquire standard edge degree information of a preset exposure image, and acquire a plurality of second edge pixel points according to the standard edge degree information; Acquire a second red pixel channel value, a second green pixel channel value, and a second blue pixel channel value according to each second edge pixel point; Acquire a second edge pixel average value and a second edge pixel variance value according to a plurality of second red pixel channel values, a plurality of second green pixel channel values, and a plurality of second blue pixel channel values; Obtaining pixel covariance according to the first edge pixel average value and the second edge pixel average value; The structural similarity is calculated according to the first edge pixel average value, the first edge pixel variance value, the second edge pixel average value, the second edge pixel variance value and the pixel covariance, wherein the calculation formula is: Wherein, J(XD) represents structural similarity, X(P1) represents the average value of the first edge pixels, X(P2) represents the average value of the second edge pixels, X(XF) represents pixel covariance, F(C1) represents the variance value of the first edge pixels, and F(C2) represents the variance value of the second edge pixels.

6. The PCB production automated exposure method according to claim 1, characterized in that: The step of obtaining the matching degree according to the image space feature, and obtaining the exposure compensation brightness according to the matching degree and the structural similarity includes: Acquire pattern intersection area, pattern union area and pattern spacing according to the image space features; Obtaining a pattern overlap rate according to the pattern intersection area and the pattern union area; The matching degree is calculated according to the pattern overlap rate and the pattern spacing, wherein the calculation formula is: P(D) = [1-T(C)]*T(J); Among them, P(D) represents the matching degree, T(C) represents the pattern overlap rate, and T(J) represents the pattern spacing; Acquire an exposure amount according to the matching degree, and acquire an exposure deviation according to the exposure amount; Acquire a local brightness mean value according to the structural similarity, and acquire a brightness difference value according to the local brightness mean value; The exposure compensation brightness is acquired according to the brightness difference value and the exposure deviation.

7. A PCB production automated exposure system, characterized in that: include: A first acquisition module is used to acquire initial alignment feature information of the PCB substrate, wherein the initial alignment feature information includes alignment mark offset information, substrate position tilt information and pattern alignment accuracy information; A second acquisition module is used to acquire an alignment error and a tilt error according to the alignment offset information and the substrate position tilt information; A first adjustment module, configured to obtain an overall exposure deviation according to the pattern alignment accuracy information, and adjust initial parameters of an exposure system according to the overall exposure deviation, alignment error, and tilt error; A third acquisition module is used to acquire in real time the illumination intensity and real-time exposure image of multiple regions of the adjusted exposure system, and acquire exposure compensation time according to the illumination of the multiple regions; A fourth acquisition module, used to acquire key features of the real-time exposure image, wherein the key features include image edge information and image space features; A fifth acquisition module, used for acquiring structural similarity according to the image edge information; A sixth acquisition module, used to acquire a matching degree according to the image space feature, and acquire an exposure compensation brightness according to the matching degree and the structural similarity; The second adjustment module is used to adjust the brightness and duration of the exposure system according to the exposure compensation brightness and exposure compensation time respectively.

8. The PCB production automated exposure system according to claim 7, characterized in that: The second acquisition module includes: A first acquisition unit, configured to acquire a mark horizontal offset, a mark vertical offset, and a mark rotation angle offset according to the alignment offset information; A second acquisition unit is used to acquire a substrate tilt angle, a substrate horizontal offset, and a substrate vertical offset according to the substrate position tilt information; A third acquisition unit is used to acquire the alignment error according to the mark horizontal offset, the mark vertical offset, the substrate horizontal offset and the substrate vertical offset; The fourth acquisition unit is used to acquire the tilt error according to the substrate tilt angle and the mark rotation angle offset.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

Images