A method for adjusting the emission angle applied to PCB blind hole detection
By symmetrically setting side light emitting bodies on both sides of the blind hole of PCB, using trigonometric function to calculate the angle, adjust the angle of the side light emitting body to evenly illuminate the blind hole, the problem of time-consuming and labor-consuming adjustment of the angle of the side light source in the prior art is solved, and efficient and reliable blind hole detection is achieved.
Patent Information
- Application Number
- CN202411424432.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-12
- Publication Date
- 2025-08-05
- Estimated Expiration
- 2044-10-12
AI Technical Summary
The prior art consumes time and effort when adjusting the angle of the side light source, making it difficult to quickly and accurately find the best angle to ensure the accuracy and efficiency of PCB blind hole detection.
By symmetrically setting two side light emitting bodies on both sides of the blind hole of the PCB, the angles A and B are calculated using the trigonometric function, and the inclination angle v between the side light emitting bodies and the vertical plane is adjusted, so that the light can evenly illuminate the entire blind hole, ensuring the accuracy and efficiency of detection.
The side light source angle is quickly and reliably adjusted, ensuring the accuracy and efficiency of blind hole detection, and avoiding the complexity and uncertainty caused by multiple adjustments.
Smart Images

Figure CN119291978B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of PCB detection light sources, and in particular to a light emitting angle adjustment method applied to PCB blind hole detection. Background Art
[0002] With the continuous development of social economy, in the electronics manufacturing industry, the requirements for the accuracy and efficiency of PCB blind hole detection are becoming increasingly higher. Side light illumination is a key factor in ensuring the accuracy of PCB blind hole detection. Due to its special structure, blind holes usually require precise lighting to clearly capture the edges and inner walls of the blind holes. In addition, different types of blind holes may require adjustment of the side light angle to achieve the required lighting area, thereby reducing the shadow inside the blind hole and achieving better imaging effects.
[0003] For example, patent application number 201910784907.4, published on November 8, 2019, discloses a side light source adjustment system and method for automated optical vision inspection equipment. The system comprises a PLC component, an area array camera focusing subsystem connected to the PLC component, a side light source adjustment component, and an industrial computer component. The side light source adjustment component includes a fixed base, a first lifting module, and a first lifting motor, which are connected in sequence. The side light source, a mounting bracket, a fastening plate, and one side of the first lifting module are connected in sequence. An angle adjustment motor is provided at one end of the mounting bracket, and the angle adjustment motor is connected to the side light source via a second motor coupling. The PLC component includes a PLC controller and a driver connected to the first lifting motor and the angle adjustment motor. The industrial computer component includes an industrial computer, which includes a calculation module and a judgment module. A person uses the PLC component to control the first lifting motor and the angle adjustment motor to quickly adjust the height and angle of the side light source. The industrial computer component calculates and determines the optimal mobile phone screen image, improving the accuracy of the adjustment results.
[0004] In the above literature, during the process of adjusting the side light source, the staff uses the PLC component to control the first lifting motor and the angle adjustment motor to adjust the height and angle of the side light source. The area array camera component automatically takes pictures, and the industrial computer component uses the side light source uniformity function to determine the optimal mobile phone screen imaging image, thereby determining the height and angle of the side light source. This literature does not determine the angle direction of the side light source at the beginning of the adjustment. Each time the side light source angle is adjusted, it is necessary to take a picture and analyze the image before making blind adjustments. The whole process is time-consuming, especially when the optimal angle can only be found after multiple adjustments and tests. Summary of the Invention
[0005] The present invention provides a light-emitting angle adjustment method applied to PCB blind hole detection, which is convenient and reliable to adjust.
[0006] To achieve the above-mentioned object, the technical solution of the present invention is: a method for adjusting the light angle applied to PCB blind via detection, which is implemented by a detection device, wherein the detection device includes a side light source module, and the side light source module includes two side light emitters arranged opposite to each other. The specific steps include:
[0007] S1: two side-light illuminators are arranged on both sides of the blind hole, and the two side-light illuminators are arranged symmetrically about the axis of the blind hole;
[0008] S2 determines the maximum luminous angle of each side-light emitter , blind hole parameters and distance parameters between the side-light illuminator and the blind hole;
[0009] S3 determines the angle A between the side-light illuminator and one side of the blind hole and the angle B between the side-light illuminator and the other side of the blind hole according to the maximum luminous angle of the side-light illuminator, the blind hole parameter, and the distance parameter between the side-light illuminator and the blind hole;
[0010] S4 adjusts the inclination angle of the side light illuminator to the vertical plane to v, so that after the rotation, the angle between the light emitted by the side light illuminator and one side of the blind hole is A, and the angle between the light emitted by the side light illuminator and the other side of the blind hole is B within the luminous angle.
[0011] The above setting determines the angle required for the light on both sides of the side light emitter to pass through the two side edges of the blind hole within the luminous angle according to the horizontal distance and vertical distance between the blind hole and the vertical plane on which the side light emitter is installed, and then adjusts the angle between the side light emitter and the vertical plane on which the side light emitter is installed according to the angle value, so that the light emitted by the side light emitter after adjustment can illuminate the entire blind hole, ensuring that the blind hole is illuminated by the side light emitter in a large range.
[0012] Furthermore, in step S2: the blind hole parameters include the width d1 of the bottom of the blind hole and the height h1 of the blind hole; the distance parameters between the side-light illuminator and the blind hole include the height h2 between the middle of the side-light illuminator and the blind hole and the horizontal distance s1 between the side of the blind hole close to the side-light illuminator and the side-light illuminator.
[0013] The above settings make it easier to calculate the corresponding angle A and angle B later through the above distance settings.
[0014] Furthermore, in step S3, the angle A of the side-light illuminator 2 irradiating one side of the blind hole is determined by tanA=s1 / h2; the angle B of the side-light illuminator 2 irradiating the other side of the blind hole is determined by tanB=h2 / (s1+d1).
[0015] With the above settings, the angle value can be determined conveniently and accurately based on trigonometric functions, and the calculation is simple.
[0016] Furthermore, step S4 includes the following steps: / 2-A;90-A≤B+ .
[0017] The above setting, through the setting of the tilt angle, makes it possible for one side of the light emitted by the side light emitting body to pass through one edge of the blind hole, and the other side of the light emitted to pass through the other edge of the blind hole, so that when the light emitting angle is greater than this angle, it can ensure that the entire blind hole has light passing through, and the side light emitting body on one side is adjusted in this way, the light emitted by the side light emitting body on the other side will illuminate the light on one side, thereby maximizing the bright area of the entire blind hole.
[0018] Furthermore, after step S4, the following step is further performed: if 90-A-B≤ , you can choose another side-light illuminator with a different luminous angle, and adjust the tilt angle v so that the tilt angle v can meet the requirement of light v≥90- / 2-A.
[0019] The above setting can adjust the side light illuminator to ensure the accuracy of detection when the angle B does not meet the requirements.
[0020] Furthermore, after step S4, the method further includes: S6, installing the side-light illuminator on the detection device according to the adjusted tilt angle v, and then using the detection device to obtain a photo of the blind hole using the adjusted side-light illuminator, and then comparing the bright area of the obtained blind hole with the bright area of the preset blind hole. If the bright area in the obtained blind hole photo is smaller than the bright area in the preset blind hole photo, v can be further increased, and then the detection can be continued after the tilt angle v is adjusted, until the bright area in the blind hole photo matches the bright area in the preset blind hole photo.
[0021] The above settings are further confirmed by image detection after adjusting the tilt angle, thereby ensuring the reliability of the adjustment. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 This is a schematic diagram of the vertical installation of the side-light illuminator in the present invention.
[0023] Figure 2 Schematic diagram of adjusting the angle v1 of the side-light illuminator in the present invention.
[0024] Figure 3 Schematic diagram of adjusting the angle v2 of the side-light illuminator in the present invention.
[0025] Figure 4 Schematic diagram of the blind hole area obtained by testing and the preset blind hole area in the present invention.
[0026] Figure 5 This is a diagram showing the arrangement of the side-light illuminator on the detection device in the present invention.
[0027] Figure 6 Flowchart of the present invention.
[0028] Description of the accompanying figures: 1-blind hole; 2-side light illuminator; 3-detection device. DETAILED DESCRIPTION
[0029] like Figure 1-3 As shown, a method for adjusting the light angle applied to PCB blind hole detection includes a side light source module, which includes two side light emitters 2. The specific steps include:
[0030] S1: two side-light illuminators 2 are arranged on both sides of the blind hole 1, and the two side-light illuminators 2 are arranged symmetrically on the axis of the blind hole 1;
[0031] S2 determines the maximum luminous angle of each side-light illuminator 2 , the width d1 of the bottom of the blind hole, the height h1 of the blind hole, the height h2 between the middle of the side-light illuminator 2 and the blind hole, and the horizontal distance s1 between the side of the blind hole close to the side-light illuminator 2 and the side-light illuminator 2; Among the above parameters, the maximum luminous angle of each side-light illuminator 2 It can be measured by optical instruments, and the parameters of blind holes can be measured by distance meters, etc.
[0032] S3 determines the angle A between the side-light illuminator 2 and the side-light illuminator 2 according to the horizontal distance s1 between the side of the blind hole close to the side-light illuminator 2 and the height h2 between the middle of the side-light illuminator 2 and the blind hole, and is determined using the following formula (1):
[0033] tanA=s1 / h2(1)
[0034] The angle B between the side-light illuminator 2 and the other side of the blind hole is determined based on the height h2 between the middle of the side-light illuminator 2 and the blind hole and the distance between the side of the blind hole away from the side-light illuminator 2. The angle B is determined using the following formula (2):
[0035] tanB=h2 / (s1+d1)(2);
[0036] The blind hole S4 is calculated to adjust the inclination angle of the side light illuminator 2 to the vertical plane to be v, so that after the rotation, the angle between the light emitted by the side light illuminator 2 and one side of the blind hole within the luminous angle is A, and the angle between the light emitted by the side light illuminator 2 and the other side of the blind hole is B.
[0037] Specifically, the tilt angle ;
[0038] The derivation process of the above tilt angle v is as follows Figure 2 As shown,
[0039] When the side-light illuminator 2 is rotated by an angle v with respect to the vertical plane, one side of the light emitted by the side-light illuminator within the luminous angle passes through one side of the blind hole and enters the blind hole, and then the other side of the light emitted by the side-light illuminator passes through the other side of the blind hole, so that the light within the entire luminous angle passes through the blind hole. The maximum tilt angle is when the light emitted from the outermost side of the luminous angle passes through the edge of one side of the blind hole and the edge of the other side of the blind hole respectively. If the side-light illuminator is continued to be rotated so that the luminous angle covers more blind hole areas, the minimum rotation angle should be that the edge of the luminous angle is rotated to one side of the blind hole and the edge of the other side of the luminous angle is rotated to the edge of the other side of the blind hole. Figure 2 The middle dotted line indicates that all the light within the luminous angle range passes through the blind hole after rotation.
[0040] Therefore, the light on both sides of the luminous angle passes through the two sides of the blind hole respectively, and the angle A can be calculated by formula (1), and then according to ,in is the angle between the side light illuminator 2 and the light passing through one side of the blind hole 2 after rotation. The formula is that the sum of the angles between the two sides of the luminous angle and the side light illuminator 2 is 180 degrees.
[0041] and ;
[0042] thereby .
[0043] In addition, in order to ensure that the light on the other side of the luminous angle is at the edge of the other side of the blind hole, the maximum angle A is the luminous angle and the angle B, if the luminous angle continues to expand outward, making the luminous angle expand outward, there will be light passing through the other side of the blind hole, such as Figure 3 As shown, the rotation angle v2 is smaller than v1, so that the emitted light passes through the other side of the blind hole and is within the luminous angle, according to 90-A -B≤ .
[0044] According to steps S2-S4, the inclination angles of the side-light illuminators on both sides are adjusted so that the two side-light illuminators are symmetrically arranged.
[0045] In another embodiment, after step S4, the method further includes:
[0046] If S5 does not meet 90-A -B≤ , you can choose another side-light illuminator with a different luminous angle, and adjust the tilt angle v so that the tilt angle v can satisfy the light v≥90- / 2-A.
[0047] This can ensure that the light on both sides of the side-light illuminator can better meet the requirements within the luminous angle.
[0048] In yet another embodiment, after step S4, the method further includes:
[0049] S6: The side-light illuminator 2 is mounted on the detection device according to the adjusted tilt angle v, and then the detection device uses the adjusted side-light illuminator 2 to obtain a photo of the blind hole, and then compares the obtained bright area of the blind hole with the bright area of the preset blind hole, such as Figure 5 As shown, if the bright area S1 in the obtained blind hole photo is smaller than the bright area S2 in the preset blind hole photo, v can be further increased, and then the detection can be continued after adjusting the tilt angle v, until the bright area in the blind hole photo matches the bright area in the preset blind hole photo. If the bright area in the obtained blind hole photo is greater than or equal to the bright area in the preset blind hole photo, no further adjustment is required to achieve detection.
[0050] This can prevent the problem of mismatch between the brightness of the blind hole detected and the actual brightness caused by installation errors after installation, and can also avoid the problem of mismatch between detection during the detection process, further ensuring the stability of detection.
[0051] When selecting the side-light illuminator 2, the luminous angle should be larger than the illumination area angle required by the blind hole 1 so as to meet the illumination needs of the blind hole 1. This can not only improve the uniformity and efficiency of the lighting, but also avoid the generation of shadows due to insufficient lighting.
[0052] like Figure 5 As shown, the detection device 3 includes a frame (not shown in the figure) and a linear array scanning camera, and then the side light source module is arranged below the linear array scanning camera. The side light source module includes two side light emitting bodies 2, and the two side light emitting bodies 2 are arranged opposite to each other. The side light emitting bodies 2 are arranged on the linear array scanning camera mounting frame through a mounting plate. A mounting hole for the side light emitting body 2 is provided on the mounting frame, and there is a gap between the mounting hole and the side light emitting body 2. The inclination angle of the side light emitting body 2 can be adjusted by the mounting plate on the side light emitting body 2.
[0053] Two side light illuminators 2 are arranged opposite to each other above the blind hole 1. The two side light illuminators 2 illuminate the blind hole 1 from two directions, and the two side light illuminators 2 are arranged at the same adjustment angle v, so that the light inside the blind hole 1 can be more uniform.
[0054] The working principle of the present invention is as follows: before adjusting the angle of the side-light illuminator 2, the required angle for the light on both sides of the side-light illuminator to pass through the two side edges of the blind hole within the luminous angle is determined according to the horizontal distance and vertical distance between the blind hole and the vertical plane on which the side-light illuminator is installed, and then the angle between the side-light illuminator 2 and the vertical plane on which the side-light illuminator is installed is adjusted according to the angle value, so that the light emitted by the side-light illuminator 2 after adjustment can illuminate the entire blind hole, ensuring that the blind hole is illuminated by the side-light illuminator in a large range, thereby improving the reliability of detection, and the tilt angle can be roughly adjusted first according to information such as the parameter value of the blind hole, without the need to determine the adjustment direction based on the image situation, thereby making it impossible to meet the requirements after multiple adjustments, resulting in a complex adjustment method.
Claims
1. A method for adjusting the light angle for PCB blind via detection, implemented by a detection device comprising a side light source module, characterized in that: The side light source module includes two side light emitters arranged opposite to each other, and the specific steps include: S1: two side-light illuminators are arranged on both sides of the blind hole, and the two side-light illuminators are arranged symmetrically about the axis of the blind hole; S2 determines the maximum luminous angle of each side-light emitter , blind hole parameters and distance parameters between the side-light illuminator and the blind hole, the blind hole parameters include the width d1 of the bottom of the blind hole and the height h1 of the blind hole; the distance parameters between the side-light illuminator and the blind hole include the height h2 between the middle of the side-light illuminator and the blind hole and the horizontal distance s1 between the side of the blind hole close to the side-light illuminator and the side-light illuminator; S3 determines the angle A between the side-light illuminator and one side of the blind hole and the angle B between the side-light illuminator and the other side of the blind hole according to the maximum luminous angle of the side-light illuminator, the blind hole parameters, and the distance parameters between the side-light illuminator and the blind hole. The angle A between the side-light illuminator and one side of the blind hole is determined by tanA=s1 / h2; the angle B between the side-light illuminator and the other side of the blind hole is determined by tanB=h2 / (s1+d1); S4 adjusts the inclination angle of the side light illuminator to the vertical plane to v, so that after the rotation, the angle between the light emitted by the side light illuminator and one side of the blind hole is A, and the angle between the light emitted by the side light illuminator and the other side of the blind hole is B, and the inclination angle v is ≥ 90- / 2-A;90-A≤B+ After adjustment, the light emitted by the side light illuminator can illuminate the entire blind hole.
2. The method for adjusting the light angle for PCB blind via detection according to claim 1, wherein: After step S4, the following steps are also included: if 90-A-B≤ , you can choose another side-light illuminator with a different luminous angle, and adjust the tilt angle v so that the tilt angle v can meet the requirement of light v≥90- / 2-A.
3. The method for adjusting the light angle for PCB blind via detection according to claim 1, wherein: After step S4, the method further includes: S6 installing the side-light illuminator on the detection device according to the adjusted tilt angle v, then using the detection device to obtain a photo of the blind hole using the adjusted side-light illuminator, and then comparing the bright area of the obtained blind hole with the bright area of the preset blind hole. If the bright area in the obtained blind hole photo is smaller than the bright area in the preset blind hole photo, v can be further increased, and then the detection is continued after the tilt angle v is adjusted, until the bright area in the blind hole photo matches the bright area in the preset blind hole photo.
Citation Information
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Side light source adjusting system and method applied to automatic optical visual inspection equipment
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