TWI833973B - Wire measuring system and method for board inspection - Google Patents

Abstract

The present invention provides a wire measuring system for board inspection, which comprises a first light source, a second light source, an image capturing device, and an image analysis device. The first light source provides a first color light to enhance the first region feature of the board. The second light source provides a second color light to enhance the second region feature of the board. The image capturing device captures the image of the board to obtain the first region feature and the second region feature. The image detection device is connected to the image capturing device to analysis the first region feature and the second region feature so as to obtain a wire information.

Description

Line measurement system and method for substrate

The present invention relates to a circuit measurement system and method, and in particular, to a circuit measurement system and method for a substrate that improves circuit contrast through multi-color light sources.

With the development of fully automated industry, Automatic Optical Inspection (AOI) has been widely used in the appearance inspection of circuit board assembly production lines in the electronics industry and replaced the previous manual visual inspection (Visual Inspection).

The automatic optical identification system is a common representative method in industrial processes. The main method is to use a camera device to capture the surface state of the object to be tested, and then use computer image processing technology to detect defects such as foreign matter or pattern abnormalities. Due to the use of non-contact Type inspection, so it can be used to inspect semi-finished products during the production line.

The basic principle of the general automatic optical identification system is to use imaging technology to compare whether there is too much difference between the object to be tested and the standard image to determine whether the object to be tested meets the standard. Therefore, the quality of the automatic optical identification system basically depends on the camera. The resolution, imaging capabilities and image recognition technology of the device.

With the increasing frequency of circuit signals and the trend of increasingly thinner circuit board circuits, the cross-sectional area consistency of circuit board circuits has become more critical to the impact of circuit characteristics such as resistance and impedance. Slight changes will lead to the final electrical appliance performance not being as expected. .

Traditional circuit board line inspections mostly use black and white cameras and diffuse light sources, which can make it difficult to identify the upper line and the lower line. Especially when the edge of the upper line has an arc corner, the distinction is particularly difficult, resulting in line width measurement. Inaccuracy, and incorrect calculation of line cross-sectional area.

On the other hand, when traditionally conducting three-dimensional inspection of circuits, conjugate microscopy, triangular reflection technology, white light interference technology, etc. are mainly used to build three-dimensional models using point measurements. The time is too slow and it is difficult to conduct a large number of inspections. Due to the limitations of point measurement, only partial height information can be obtained, and it is difficult to combine it into complete line cross-sectional area information.

The main purpose of the present invention is to provide a circuit measurement system for substrates, which includes a first light source, a second light source, an image capture device, and an image processing device. The first light source provides a first color light beam to a substrate to display a first area feature of the substrate. The second light source provides a second color beam to the substrate to display a second area feature of the substrate. The image capturing device captures images of the substrate to obtain the first area features and the second area features. The image processing device is connected to the image capturing device and analyzes the first area characteristics and the second area characteristics to obtain a line information.

Another object of the present invention is to provide a circuit measurement system for substrates, including a first light source group, a first image capture device, a second light source group, a second image capture device, and a Image processing device. The first light source group provides a first color light beam and a second color light beam to the substrate to display a first line image feature of the substrate. The first image capturing device is disposed on the top view direction side of the substrate to capture the first line image characteristics. The second light source group provides the first color light beam and the second color light beam to the substrate to display a second line image feature of the substrate. The second image capturing device is disposed on the side view direction side of the substrate to capture the second line image characteristics. The image processing device analyzes the first line image characteristics and the second line image characteristics to obtain line information.

Therefore, the present invention can effectively increase the image contrast between multiple characteristic areas on the line, thereby improving the accuracy of line measurement, thereby increasing the accuracy of detection. In addition, the present invention can highlight the R-angle image between the boundaries of feature areas through the effect of two-color light mixing, so that the boundaries between multiple feature areas can be effectively extracted to accurately measure various values of the line. Furthermore, in addition to improving the contrast between feature areas, the present invention can also highlight defects caused by uneven line surface defects due to different color expressions at different angles, thereby increasing the accuracy of detection.

The detailed description and technical content of the present invention are described below with reference to the drawings. Furthermore, for the convenience of explanation, the proportions of the drawings in the present invention may not be drawn according to the actual proportions. The drawings and their proportions are not intended to limit the scope of the present invention and are explained here.

In order to facilitate understanding of the main technical concepts of the present invention, the main structure of the present invention is first described in detail. Please refer to "Figure 1" first, which is a block diagram of the line measurement system of the present invention. The circuit measurement system 100 in this embodiment mainly includes an image capturing device 10, a first light source 20, a second light source 30, and an image processing device 40.

The image capturing device 10 is used to image capture the substrate Ob to obtain an image of the substrate. The image capturing device 10 includes, but is not limited to, a color camera for photographing the substrate Ob on the detection area IA. The substrate Ob includes at least one substrate circuit. In one embodiment, the image capturing device 10 may be an area scan camera or a line scan camera.

The first light source 20 provides a first color light beam to the substrate Ob to display the first area characteristics of the substrate circuit. Preferably, the first color light beam can be a basic color light source such as red, green, or blue. In addition to the light sources of the above colors, the first color light beam can also be Other light sources of different colors are not limited in the present invention. The first light source 20 is disposed above the detection area 1A and is aligned to the substrate circuit of the substrate Ob at a first angle. Since the first light source 20 is output to the substrate circuit through a specific illumination angle, the substrate image captured by the image capturing device 10 at the corresponding position will show a high contrast, and the captured substrate image will make the substrate Faces at specific angles are highlighted. The first area features include image features on the upper plane of the circuit or the bottom plane of the substrate.

The second light source 30 provides a second color beam to the substrate to display the second area characteristics of the substrate. Preferably, the second color light beam can be a basic color light source such as red, green, or blue. In addition to the light sources of the above colors, the second color light beam can also be Other light sources of different colors are not limited in the present invention. The second light source 20 is disposed on one side of the detection area 1A and is aligned to the substrate circuit of the substrate Ob at a second angle. The second area features include image features on the line sidewall.

The color of the light beam output by the second light source 30 is different from the color of the light beam output by the first light source 20. The color expression between different areas can be improved through the expression of light beams of different colors, thereby highlighting the structural boundary texture.

Since the angle and color of the second light source 30 are different from those of the first light source 20 , the area highlighted by the first light source 20 (such as the first area feature) in the circuit of the substrate will be different from the area highlighted by the second light source 30 in the substrate. The highlighted areas (such as second area features) in the circuit are different, so that in the image of the substrate circuit, areas with different relative angles to the first light source 20 and the second light source 30 have different color presentations, which is beneficial to the machine. Visually delineate regions of interest.

On the other hand, by mixing the light beams of the first color and the second color, the circuit image of the substrate Ob will include a third area feature displayed on the substrate. For example, a mixed light effect will occur at the position of the chamfer/R angle (such as the R angle between the surface and the surface connection) on the substrate circuit. Through the mixed light effect, the image at the R angle position will be compared to other plane areas. It is highlighted so that the mixed color area can be used as an area of interest or the boundary of the image and can be easily read by machine vision. The third region features include image features at the junction of the upper plane of the circuit and the circuit sidewall, or image features at the junction of the bottom plane of the substrate and the circuit sidewall.

After the image capture device 10 captures the image of the substrate Ob, the first area feature, the second area feature, and the third area are generated through the first color light beam and the second color light beam in the captured substrate image. Characteristics.

The image processing device 40 is connected to the image capturing device 10 to obtain the substrate image captured by the image capturing device 10, and obtains the first area feature and the second area feature from the substrate image. , and the third area characteristics, and obtain line information by analyzing the first area characteristics, the second area characteristics, and the third area characteristics. Specifically, the image processing device 40 can load the storage unit (not shown) through the processor to access the image analysis program, and perform the image analysis function according to the program. Specifically, the image analysis program can be, for example, an image pre-processing program, image segmentation and positioning, defect detection (gradientization, region growth, growth compensation, etc.), machine learning system (Machine Learning), deep learning system (Deep Learning) etc., are not limited in the present invention.

In a feasible embodiment, the image capture device 10 includes a filter (which can be a physical filter or a software filter), and the filter is used to filter out colors different from those of the first light source and the second light source. The light source, through the above method, can reduce the image noise generated by the ambient light source and further increase the detection performance.

Please refer to "Figure 2" first, which is a block diagram of the first embodiment of the present invention. In this embodiment, the circuit measurement system 200 configures a specific optical structure to enhance the contrast of the structural features in the substrate image. The line measurement system 200 includes an image capturing device 10A, a first light source 20A, a second light source 30A, and an image processing device 40A.

In this embodiment, the optical axis direction of the image capturing device is perpendicular to the plane of the substrate (as shown in Figure 2, the optical axis direction of the image capturing device 10A is arrow A1 and the substrate plane F2).

The configured first light source 20A in this embodiment includes a coaxial light source, which is disposed in the shooting direction of the image capturing device. Since the direction of the light output is generally consistent with the direction of the optical axis of the image capture device 10A, the coaxial light output by the first light source 20A will be reflected into the lens of the image capture device 10A through the surface perpendicular to the direction of the optical axis. Therefore, on the substrate The brightness of the first color will be enhanced between the line upper plane US and the substrate bottom plane BS in the image, so that there is a high contrast between the line upper plane US (and the substrate bottom plane BS) and the line sidewall SS in the substrate image.

The configured second light source 30A in this embodiment includes a lateral light source to provide lateral illumination to the substrate Ob. In one of the possible embodiments, the lateral light source ring is disposed on the periphery of the coaxial light source to provide lateral light sources (such as ring light sources) to the object to be viewed. Generally speaking, the side wall of the substrate circuit is basically an inclined surface with a specific inclination angle. The lateral light source fills the side wall of the substrate circuit through the side. When the ring light source is kept at an appropriate distance from the substrate circuit, The side light source (second light source 30A) will enhance the brightness of the second color of the circuit sidewall. Based on the above optical combination, an obvious color difference will be produced in the substrate image between the circuit upper plane US and the circuit sidewall SS of the substrate circuit. In the embodiment of the ring light, the ring light can provide light at a specific angle to the object to be measured (for example, through a light guide, an optical fiber, a reflector, a refractor, or other optical elements), thereby adjusting the angle of the lateral light source.

At the position of the structure junction, the line illuminated by the coaxial light source and the lateral light source, the image feature (R angle boundary C1) at the intersection of the line's web plane US and the line side wall SS, and the intersection of the substrate bottom plane BS and the line side wall SS The image features at (R angle boundary C2) produce a mixed light effect. Through the mixed light effect, the positions of the images of R angle boundaries C1 and C2 relative to the line upper plane US, line sidewall SS, and substrate bottom plane BS are highlighted. , so that the boundary can be used as the boundary of the area of interest or image and can be easily segmented by machine vision.

In a preferred embodiment, in order to prevent the light source from interfering with the imaging substrate of the image capturing device 10A, the coaxial light source is disposed in the optical axis direction of the image capturing device 10A, and the lateral light source system is disposed around the periphery of the coaxial light source. position.

In a feasible embodiment, the image capturing device 10A includes a filter (which can be a physical filter or a software filter), and the filter is used to filter out the light associated with the first light source 20A and the second light source 30A. Light sources of different colors can reduce the impact of noise generated by ambient light sources on the substrate image through the above methods, further increasing detection performance.

Since different colors are reflected between the circuit upper plane US and the circuit sidewall SS in the substrate image, a second filter (which can be a physical filter or filter software) can be further set to separate the different colors. The colored areas are respectively masked to facilitate the image processing device 40A to segment the areas of interest, and further obtain line information from the segmented images. For example, when the coaxial light source is a red light source (Red) and the lateral light source is a green light source (Green), the red filter can be used to display the sidewall area in the substrate image, and the green filter can be used to display the substrate image. The flat area on the line in the line.

The following describes another feasible embodiment of the present invention. Please also refer to "Fig. 3", which is a block schematic diagram of the second embodiment of the present invention. In this embodiment, the line measurement system 300 is configured with another optical architecture, which can also achieve the effect of enhancing the contrast of structural features in the substrate image. The line measurement system 300 includes an image capturing device 10B, a first light source 20B, a second light source 30B, and an image processing device 40B.

In this embodiment, the optical axis direction (arrow A2) of the image capturing device 10B and the substrate plane F2 present a shooting angle. In a feasible implementation, the shooting angle can preferably be between Between 0 degrees and 90 degrees, changes in these angles are not limited in the present invention.

The configured first light source 20B in this embodiment includes a coaxial light source or a forward light source relative to the plane of the substrate. The coaxial light source or the forward light source faces the upper side of the substrate circuit and outputs light to the substrate Ob, and enhances the first color brightness of the circuit upper plane US and the substrate bottom plane BS in the substrate image by providing the upper side light source, so that There is a relatively high contrast in the first color between the circuit upper plane US (and the substrate bottom plane BS) and the circuit sidewall SS in the substrate image.

The configured second light source 30B in this embodiment includes a lateral light source. The lateral light source preferably includes a light guide to improve the directivity of the light source and provide lateral light to the substrate Ob. The lateral light source is aligned from the side to the substrate circuit, and the second color brightness of the circuit sidewall in the substrate image is enhanced through the oblique directional light source, so that the circuit sidewall SS in the substrate image is consistent with the circuit upper plane US (and There is a relatively high contrast in the second color between the substrate bottom plane BS).

At the position of the structure junction, the line illuminated by the coaxial light source (or forward light source) and the lateral light source, the image feature (R angle boundary C1) at the intersection of the line web plane US and the line side wall SS, and the bottom plane of the substrate The image features (R corner boundary C2) at the junction of BS and line sidewall SS produce a mixed light effect. Through the mixed light effect, the images of R corner boundaries C1 and C2 will be relative to the upper plane US of the line, the line sidewall SS, and the bottom plane of the substrate. The position of the BS is highlighted, so that the boundary can be used as the intersection of the area of interest or the image and can be easily segmented by machine vision.

The optical configuration relationship between the image capturing device 10B, the first light source 20B and the second light source 30B is mainly determined by the angle between the circuit side wall of the substrate circuit and the upper plane of the circuit. The circuit structure is determined by the manufacturing process or requirements. When adjusting, the angle relationship between the devices can also be adjusted accordingly. In a preferred embodiment, the imaging angle α between the optical axis direction (arrow A2) of the image capturing device 10B and the light output direction A3 of the coaxial light source (or forward light source) is between 20 degrees and 40 degrees; the angle β between the optical axis direction (arrow A2) of the image capture device 10B and the light output direction A4 of the side light source is between 30 degrees and 50 degrees. These angles can be fine-tuned up or down according to the actual situation. , and the output intensity of the first light source 20B and the second light source 30B can also be adjusted according to actual needs.

In order to increase the computing efficiency and accuracy of the image processing device 40B, in a feasible embodiment, the image capturing device 10B includes a filter (which can be a physical filter or a software filter). The filter is used to filter Except for any light source of a different color from the first light source and the second light source among the three color light sources of red, green, and blue, through the above method, the influence of the ambient light source on the substrate image can be reduced , further increasing detection efficiency.

Through the above light source configuration, the images of the circuit upper plane US, the substrate bottom plane BS and the circuit sidewall SS in the substrate image will respectively highlight two different color expressions. At this time, you can set the filter (can be a physical filter) Or filter software), the areas of different colors are respectively shielded, so as to facilitate the image processing device 40B to segment the area of interest and obtain the line information from the segmented image. For example, when the coaxial light source is a red light source (Red) and the lateral light source is a green light source (Green), the red filter can be used to display the line sidewall SS in the substrate image, and the green filter can be used to display the substrate The upper plane of the line US and the bottom plane of the substrate BS in the image.

The hardware device of the present invention has been described in detail above. The following will continue to give a more detailed description of the collaborative work and software programs executed by the hardware. Referring to "Figure 4" first, before shooting, provide the first light source 20 of the first color and the second light source 30 of the second color to the substrate circuit of the substrate to display the first area characteristics and the second area of the substrate circuit. Features (step S101). Specifically, the first light source 20 and the second light source 30 simultaneously provide the first color light beam and the second color light beam to the substrate surface, and respectively display the circuit upper plane US( of the substrate circuit) in the image in different colors. The bottom plane of the substrate BS) and the circuit sidewall SS. In this step, the individual output powers of the two sets of lights (the first light source 20 and the second light source 30 ) can be adjusted based on machine vision or the human eye to further highlight the upper plane US (the bottom plane of the substrate) of the line. BS) and the color difference of the SS image on the side wall of the line.

After the output configuration of the light source is confirmed, the substrate is photographed through the image capturing device 10 to obtain an image of the substrate (step S102). The image capture device 10 can be a camera device that takes fixed-point shots, or it can be a camera device that cooperates with a mobile stage to take multi-point partial shots or take path-type shots along a line, which is not limited in the present invention.

After the shooting is completed, the image processing device 40 obtains the substrate image, and obtains the circuit information from the substrate image (step S103). Specifically, in this step, the image processing device 40 analyzes the circuit information in the substrate image through an image analysis algorithm. Among them, the line information described here can be the upper width of the line, the lower width of the line, the width of the side wall area, the area of the side wall area or/and the surface quality of the side wall area, etc., or it can be the size, shape, curvature of each area of the line. , angles, surface defects and other visual defects, or visual defects that are difficult to distinguish with the naked eye under ordinary light sources, are not limited in the present invention. Generally, after the substrate circuit is formed during the manufacturing process, its cross-sectional shape is roughly trapezoidal. Depending on the actual situation, the cross-sectional shape of the substrate circuit may also be rectangular. For substrates with trapezoidal lines, you can choose to shoot from a bird's-eye view or from a side angle (obliquely upward); for substrates with rectangular lines, it is best to shoot from a side angle to facilitate obtaining side wall images.

For convenience of explanation, in the present invention, a common circuit pattern with a trapezoidal cross-section is used for explanation. The substrate image (as shown in FIG. 5) captured by the image capture device 10 can be mainly divided into the upper circuit area on the top side of the substrate circuit. Among the planar area R1, the line sidewall areas R2 and R3 respectively provided on both sides of the line upper plane area R1, the substrate bottom plane area R4 on the periphery of the line sidewall areas R2 and R3, the line upper plane area R1 and the line sidewall area R2 The R corner area CE1 between the line upper plane area R1 and the line side wall area R3, the R corner area CE3 at the connection between the line side wall area R2 and the substrate bottom plane area R4, and the line side wall area R3 and The R corner area CE4 at the junction of the bottom plane area R4 of the substrate. The optical configuration of the first light source 10 and the second light source 20 will produce obvious differences in color between the upper line planar area R1, the line sidewall areas R2 and R3, and the substrate bottom planar area R4. In addition, through the light mixing effect, the R-angle areas CE1 and CE2 between the line upper plane area R1 and the line sidewall areas R2 and R3, and the R-angle areas CE3 and CE3 between the line sidewall areas R2 and R3 and the substrate bottom plane area R4. Through the light mixing effect, CE4 forms color strips that are different in color from the upper plane area R1 of the circuit, the sidewall areas R2 and R3 of the circuit, and the plane area R4 at the bottom of the substrate. The color bands formed by the R-angle areas CE1, CE2, CE3, and CE4 will be used as significant boundaries that can be referenced in the image, which is beneficial to image segmentation processing.

The image processing device 40 sets a filter according to the image and further sets a threshold (for example, binarization processing) to easily segment the images of two regions of interest (as shown in FIG. 6 ), in which the image I1 is the segmented substrate circuit. The image of the upper plane area R1 of the circuit. The image I2 is the image of the divided substrate circuit sidewall areas R2 and R3. By measuring the width of the two sets of line segments in the image, the upper width of the circuit UW1 and the first side wall can be obtained. Area width SW1, and second side wall area width SW2 and other line information. Since the color band formed by the R corner areas CE1, CE2, CE3, and CE4 may have a certain width, when calculating various data of the line, the R corner areas CE1, CE1, and CE4 can be divided by preset error values or according to appropriate ratios. The widths of CE2, CE3, and CE4 are corrected to obtain line width UW1, first side sidewall area width SW1, and second side sidewall area width SW2 that are close to actual values.

The image segmented by the image processing device 40 can be error corrected through the pixel width, the internal parameters of the camera, and the shooting angle to further calculate the size of each area in the image and further obtain various circuit information of the substrate. In addition to image analysis of the boundaries of the substrate circuits in the image, the captured images can be used for defect detection; defects in the substrate circuits (such as copper leakage, uneven surfaces, ink, etc.) The colors displayed in the image will be different due to different texture colors or irregular surfaces. In the previous process of color masking and threshold setting, these defect features will also be displayed. The image processing device 40 can realize the function of defect detection based on the image of the substrate circuit by marking the location of the defect.

In addition to the above embodiments, the present invention can also be used to generate a three-dimensional image of the substrate circuit by acquiring various circuit information in the image. Please refer to "Figure 7" below, which is a block diagram of the third embodiment of the present invention. This embodiment is similar to the previous embodiment, so the same parts will not be described again below.

The line measurement system 400 of this embodiment mainly includes a first image capture device 10C, a second image capture device 20C, a first light source group 30C, a second light source group 40C, and a connection or coupling to The image processing device 50C of the first image capturing device 10C and the second image capturing device 20C.

The first image capture device 10C described in this embodiment is disposed on the top view direction side of the substrate Ob to capture the detection area IA1 and obtain a top view image of the first line on the substrate Ob to capture a first Line image characteristics. The top view direction side mentioned here refers to the position above the plane of the substrate, and the optical axis direction of the first image capturing device 10C is substantially perpendicular to the plane of the substrate. The combination of the first image capturing device 10C and the first light source group 30C can be the same as the configuration of the first embodiment. The first light source group 30C includes a coaxial light source 31C and a lateral light source 32C; the coaxial light source 31C is configured In the shooting direction of the image capturing device 10C, the lateral light source 32C is disposed around the periphery of the coaxial light source 31C. The first image line characteristics include providing the first color light beam (coaxial light source 31C) to the first area feature displayed on the substrate, and providing the second color light beam (lateral light source 32C) to the first area feature displayed on the substrate. two area features, and a third area feature displayed on the substrate by mixing the first color light beam and the second color light beam.

The second image capture device 20C described in this embodiment is disposed on the side view direction side of the substrate Ob, and is used to capture the detection area IA2 and obtain the side view image of the second line on the substrate Ob, so as to capture a Second line image characteristics. In this embodiment, the optical axis direction of the second image capturing device 20C and the substrate plane present a shooting angle, and the shooting angle is between 0 degrees and 90 degrees. The side view direction mentioned here refers to the positive lateral position or the obliquely upward position of both sides of the substrate circuit while maintaining an appropriate inclination angle with the circuit. The combination of the second image capturing device 20C and the second light source group 40C can be the same as the configuration of the second embodiment. The second light source group 40C includes a coaxial light source 41C (or a positive direction relative to the plane of the substrate). light source), and a lateral light source 42C; the imaging angle between the optical axis direction of the second image capturing device 20C and the light output direction of the forward light source is between 20 degrees and 40 degrees; the second image The angle between the optical axis direction of the capture device 20C and the light output direction of the side light source 42C is between 30 degrees and 50 degrees. The second image circuit characteristics include providing the first color beam (coaxial light source 41C (or forward light source)) to the first area feature displayed on the substrate, providing the second color beam (side light source 42C) to a second area feature displayed on the substrate, and a third area feature displayed on the substrate by mixing the first color light beam and the second color light beam.

In the present invention, the first image capturing device 10C and the second image capturing device 20C can provide four kinds of light sources to the substrate circuit at the same time and capture images of the substrate circuit at the same time. In another feasible embodiment, the first set of images can be captured by time-sharing shooting and providing light sources (for example, in a program, turning on the combination of the first image capture device 10C and the first light source group 30C ; In another process, the combination of the second image capturing device 20C and the second light source group 40C is turned on to capture the second set of images, and the shooting time is divided into two sets of images. The changes in these embodiments are not part of this invention. The scope of the invention is intended to be limited.

In another possible embodiment, the first image capturing device 10C, the second image capturing device 20C, the first light source group 30C and the second light source group 40C can be disposed together on the same stage, so that The relative positions and relative angles between the above-mentioned devices are in a fixed state. By recording the movement value of the stage and establishing a correlation with the captured images, the characteristics of the line at each position can be confirmed. In another possible embodiment, the first image capturing device 10C, the second image capturing device 20C, the first light source group 30C and the second light source group 40C are jointly disposed on the same stage. , the first optical combination of the first image capturing device 10C and the first light source group 30C, and the second optical combination of the second image capturing device 20C and the second light source group 40C can be arranged front and back on the stage, so that The paths traveled by the first image capturing device 10C and the second image capturing device 20C are consistent (first come, first served), which increases the efficiency of detection and the accuracy of coordinate calibration.

The coaxial light source 31C of the first light source group 30C includes one of red, green, and blue light sources, and the lateral light source 32C includes any one of the red, green, and blue light sources that is different from the coaxial light source. The coaxial light source 41C (or forward light source) of the second light source group 40C includes one of red, green, and blue light sources, and the side light source 42C includes any one of the red, green, and blue light sources that is consistent with the coaxial light source. 41C (or the forward light source) light sources of different colors.

The image processing device 50C is connected or coupled to the first image capturing device 10C and the second image capturing device 20C to acquire the top view image and the side view image of the substrate, and based on the top view image and the side view image The side view image obtains and analyzes the first line image feature and the second line image feature to obtain the line information of the substrate through the first line image feature and the second line image feature. The image processing device 50C obtains the upper width of the line and the lower width of the line (that is, the sum of the upper width of the line plus the width of the first side wall area and the width of the second side wall area at the same cross-sectional position) from the top-view image. , sidewall area width, sidewall area area, or/and sidewall area surface quality and other line information, and the line information of the sidewall side view width of the substrate line is obtained through the side view image. Through the above line information, the line thickness value of the line can be calculated through the lens shooting angle, the upper line width of the line, the overall area width, and/or the obtained side wall width. The height value can be calculated by triangulation. The theorem can be deduced and will be explained later.

Continuing, please refer to "Figure 8" as well, which is a schematic cross-sectional view of the substrate (2). The image processing device 50C obtains the line width in the image , line lower width and side wall width After that, the circuit thickness of the substrate can be further obtained through trigonometric calculations. ; Among them, when the optical axis direction of the camera is orthogonal to the side wall area of the line (the projection length of the side wall entering the camera is equal to the actual length of the side wall), the side view width of the side wall can be obtained directly through distance matching ratio calculation , and the side view width via the side wall Get line thickness ; When the optical axis direction of the image capture device is not orthogonal to the line side wall area of the line, the shooting angle correction of the image capture device can be considered to obtain the actual side wall width. , side view width via side wall Get line thickness , or the side wall overlooking angle width , shooting angle, and the side wall projection length obtained from the corresponding angle of view can be directly substituted to calculate the line thickness. , is not limited in the present invention.

In another embodiment, the image processing device 50C confirms the width of the line , you can further confirm the width of the side wall's top view through the boundary between the upper plane US of the line and the side wall SS of the line. . Through Pythagorean theorem, the line thickness , side wall side view width , Side wall overlooking angle width will conform to the following formula: ;Due to the width of the side wall And side wall bird’s-eye view width is known, the line thickness can be obtained after calculation . After the line thickness H has been obtained, the line cross-sectional area of the section can be calculated and obtained through the trapezoidal formula , the calculation formula is as follows: . After obtaining the cross-sectional area, the image processing device 70C can obtain the circuit current-carrying capacity (Current-Carry Capacity) on the substrate based on the circuit cross-sectional area; the circuit current-carrying capacity can be obtained through the following equation: ;in, is the maximum current carrying capacity, is the correction coefficient, is the maximum temperature difference, is the cross-sectional area of the line. In addition, through the captured top-view images and side-view images, defects on the line can also be found through image recognition, thereby obtaining line defect information.

Although the above-mentioned line cross-sectional area shape is exemplified by a trapezoid, it can also be a rectangle or other shapes, which are not limited here. In addition, in addition to the above-mentioned formula, the current-carrying formula can also be other that can be referred to and comply with relevant standards such as IPC. Calculation formula, such as IPC-2221. In another possible embodiment, the image processing device 50C can also obtain the line current carrying capacity through a lookup table (Look up Table) using a lookup method. In the lookup table, values that do not appear in the lookup table can be calculated by the nearest neighbor method (K-Nearest Neighbor) or the insertion method (Insertion Method). This part depends on the design requirements.

Please refer to "Figure 9", which is a schematic three-dimensional image of the circuit board. In a preferred embodiment, the image processing device 70C can further obtain the target line segment path of the substrate circuit from the substrate image. , further depending on the width of the line , line lower width , the width of the side wall in side view with the target segment path , the target line segment path is obtained by combining the line cross-sectional area with the line segment path line volume. In another feasible embodiment, after obtaining multiple cross-sectional areas, the target line segment path can be obtained by multiplying the line segment cross-sectional area on each cross-section by the corresponding line segment length. line volume.

In addition to the above technical features for analyzing line information, the line information obtained by the present invention can be further used to create a three-dimensional image of the line through stereoscopic vision.

The following is a description of the three-dimensional image formation method for the substrate circuit in the present invention. Please refer to "Fig. 10" to "Fig. 15" together, which are coordinate position positioning diagrams of the substrate circuit, a top view image schematic diagram of the substrate circuit, and a schematic diagram of the substrate circuit. Schematic diagram of side view image, schematic diagram of three-dimensional image imaging of the line measurement system of the present invention (1), schematic diagram of three-dimensional image imaging of the line measurement system of the present invention (2), and schematic diagram of three-dimensional image imaging of the line measurement system of the present invention. (3), as shown in the figure:

First, please refer to "Figure 10". After receiving the top view image and the side view image of the substrate circuit, the image processing device 50 sets a plurality of continuous coordinate positions M ₁ (X ₁ , Y ₂ , Z ₃ )...M _n (X _n , Y _n , Z _n )...M _N (X _N , Y _N , Z _N ), the coordinate position can be set through the stereo vision method (Stereo Vision Algorithm), convert the image pixel coordinate system (u, v) into the world coordinate system (X _w , Y _w , Z _w ) and complete the calibration of the target coordinate position in the image; in another feasible embodiment, the complex number Each coordinate position can also be sampled from the other side boundary, the center line, or other easily identifiable reference features, which are not limited in the present invention. In another feasible embodiment, especially in the embodiment of a line scanning camera, the coordinate position can be confirmed by feedback from the data of the transfer device.

Continuing, please refer to "Figure 11" together. After setting the coordinate position, the image processing device 50C obtains the width of the line in the top-view image. , line lower width . Line width and line width The relative position between them can be determined by the bird's-eye view width of the two side walls in the bird's-eye view image. , Or the width of the two side walls when viewed from above , The ratio is obtained.

Continuing, please refer to "Figure 12". After receiving the side view image of the line, the image processing device 50C analyzes the side view width of the line in the line image. .

After the above two steps, the image processing device 50C will obtain the upper width of the line , line lower width , The width of the two side walls from the top view , , and side wall side view width , and obtain the line thickness through the above line information calculation At the same time, the coordinate position M _n (X _n , Y _n , Z _n ) to which these parameters belong is recorded at the same time.

To continue, please refer to "Figure 13" to obtain the upper width of the line. , line lower width , and line thickness , and the corresponding coordinate position M _n (X _n , Y _n , Z _n ), the image processing device 50C is based on the width of the line , line lower width and line thickness Create target cross-section images. In this step, first look down at the viewing angle width through the two side walls , Confirm the width of the line , line lower width The relative positional relationship of the line thickness When the parameter conditions are confirmed, the base length, top length, height, first side hypotenuse, and second side hypotenuse of the trapezoidal cross-section can be confirmed, and the two-dimensional shape on the cross-sectional area is determined by the above parameters. Further, it can be A two-dimensional image cross-section ST ₁ is formed. Through the created two-dimensional image cross-section, the line information of the two-dimensional image cross-section can be confirmed, thereby obtaining line defect information through the line information.

Finally, please refer to "Figure 14" and "Figure 15" together, through the plurality of continuous lines, the coordinate positions M ₁ (X ₁ , Y ₂ , Z ₃ )...M _n (X _n , Y _n , Z _n )...M _N (X _N , Y _N , Z _N ), and individually corresponding to the coordinate position M ₁ (X ₁ , Y ₂ , Z ₃ )...M _n (X _n , Y _n , Z _n )...M _N (X _N , Y _N , Z _N )'s two-dimensional image cross-section ST ₁ -ST _n -ST _N to establish an image stack STK. After completing the image stacking STK, between the coordinate positions of the image interval (M ₁ (X ₁ , Y ₂ , Z ₃ )...M _n (X _n , Y _n , Z _n )...M _N (X _N , Y _N , Z _N )) are supplemented by interpolation, thereby outputting a three-dimensional image of the substrate circuit as shown in Figure 15.

Through the restored three-dimensional image of the substrate circuit, circuit defect information can be obtained through the circuit information obtained from the cross-sectional shape, thereby confirming the type and type of defects and improving the efficiency of visual inspection by personnel.

The following diagrams are used to describe the circuit measurement method of the present invention in detail. Please refer to "Figure 16" as well, which is a schematic flow chart (2) of the circuit measurement method of the present invention, as shown in the figure:

This embodiment provides a line measurement method, which includes the following steps:

The first light source group 30C and the second light source group 40C are provided to the substrate Ob to display the first circuit image characteristics and the second circuit image characteristics of the substrate Ob (step S201).

Next, the first image capturing device 10C is provided to the top view direction side of the substrate to capture the first line image characteristics of the substrate (step S202); and the second image capturing device 20C is provided to the side view of the substrate. direction side to capture the second circuit image feature of the substrate (step S203).

A moving stage is provided to adjust the relative positional relationship between the substrate Ob, the first image capturing device 10C and the second image capturing device 20C (step S204).

In step S204, the time when the first image capture device 10C and the second image capture device 20C capture the substrate does not necessarily have to be executed sequentially. The first image capture device 10C can first execute the capture to obtain the second image capture device. A line image feature may be first captured by the second image capturing device 20C to obtain the second line image feature, or both may be performed simultaneously. This part is not limited in the present invention.

Next, the image processing device 50C is provided to receive the top view image and the side view image, and generate line information on the substrate line based on the top view image and the side view image (step S205). The circuit information of the substrate circuit includes, for example, the upper width of the circuit, the lower width of the circuit, the width of the sidewall area, the area of the sidewall area, or/and the surface quality of the sidewall area, which is not limited in the present invention.

After obtaining the circuit information, the image processing device 50C obtains the circuit cross-sectional area on the substrate according to the circuit information (step S206).

Finally, after obtaining the circuit cross-sectional area, the image processing device 50C obtains the circuit current carrying capacity on the substrate Ob based on the circuit cross-sectional area (step S207).

In summary, the present invention can effectively increase the image contrast between multiple feature areas on the line, thereby improving the accuracy of line measurement and thereby increasing the accuracy of detection. In addition, the present invention can highlight the R-angle image between the boundaries of feature areas through the effect of two-color light mixing, so that the boundaries between multiple feature areas can be effectively extracted to accurately measure various values of the line. Furthermore, in addition to improving the contrast between feature areas, the present invention can also highlight defects caused by uneven line surface defects due to different color expressions at different angles, thereby increasing the accuracy of detection.

The present invention has been described in detail above. However, what is described above is only one of the preferred embodiments of the present invention. It should not be used to limit the scope of the present invention, that is, any application based on the patent scope of the present invention shall be equal. Changes and modifications should still fall within the scope of the patent of the present invention.

100: Line measurement system 10: Image capture device 20: First light source 30: Second light source 40: Image processing device IA: Detection area Ob: Substrate 200: Line measurement system 10A: Image capture device 20A: First Light source 30A: Second light source 40A: Image processing device A1: Arrow F2: Substrate plane 300: Line measurement system 10B: Image capture device 20B: First light source 30B: Second light source 40B: Image processing device A2: Arrow A3: Light output direction A4: Light output direction α: Capture angle β: Included angle Step S101-Step 103 US: Line upper plane SS: Line side wall BS: Bottom plane of substrate C1: R angle boundary C2: R angle boundary R1: On line Web plane area R2: line side wall area R3: line side wall area R4: substrate bottom plane area CE1: R corner area CE2: R corner area CE3: R corner area CE4: R corner area I1: image I2: image UW1: upper line width Width UW2: line lower width SW1: first side side wall area width SW2: second side side wall area width 400: line measurement system 10C: first image capture device 20C: second image capture device 30C: first light source Group 31C: Coaxial light source 32C: Side light source 40C: Second light source group 41C: Coaxial light source 42C: Side light source 50C: Image processing device IA1: Detection area IA2: Detection area :Line upper width : Line lower width :Side wall side view width :Side wall side view width :line thickness :Target segment path :Side wall top view width S2: Side wall top view width ST: ₁ -ST: _N Two-dimensional image cross-section S201-S207: Steps

Figure 1 is a block diagram of the line measurement system of the present invention.

Figure 2 is a block diagram of the first embodiment of the present invention.

Figure 3 is a block diagram of the second embodiment of the present invention.

Figure 4 is a schematic flow chart (1) of the line detection method of the present invention.

Figure 5, schematic diagram of the circuit board.

Figure 6 is a schematic diagram of the segmentation of the region of interest in the present invention.

Figure 7 is a block diagram of the third embodiment of the present invention.

Figure 8 is a schematic cross-sectional view of the circuit board.

Figure 9 is a schematic three-dimensional image of the circuit board of the present invention.

Figure 10 is a coordinate positioning diagram of the substrate circuit.

Figure 11 is a schematic top view of the circuit board.

Figure 12 is a schematic side view of the circuit board.

Figure 13 is a schematic diagram (1) of the three-dimensional image imaging of the circuit measurement system of the present invention.

Figure 14 is a schematic diagram (2) of the three-dimensional image imaging of the circuit measurement system of the present invention.

Figure 15 is a schematic diagram (3) of the three-dimensional image imaging of the circuit measurement system of the present invention.

Figure 16 is a schematic flow chart (2) of the line measurement method of the present invention.

100: Line measurement system

10:Image capture device

20:First light source

30:Second light source

40:Image processing device

IA: detection area

Ob: substrate

Claims (23)

A circuit measurement system for a substrate, including: a first light source that provides a first color beam to a substrate to display a first area feature of the substrate; a second light source that provides a second color beam to the substrate on the substrate to display a second area feature of the substrate; an image capture device to capture an image of the substrate to obtain the first area feature and the second area feature; and an image processing device connected to the image The acquisition device analyzes the characteristics of the first area and the characteristics of the second area to obtain a line information. The line information includes the upper width of the line, the lower width of the line, the width of the side wall area, the area of the side wall area or/and the surface of the side wall area. quality. As described in claim 1 of the patent application, the circuit measurement system for a substrate, wherein the circuit image of the substrate captured by the image capture device includes a third area feature, mixing the first color and the second Colored light beams are displayed on the substrate. The line measurement system for substrates as described in item 2 of the patent application, wherein the first area features include image features on the upper plane of the line or the bottom plane of the substrate; wherein the second area features include on the side walls of the line The image characteristics of Image characteristics at the junction of walls. As described in item 1 of the patent application, the circuit measurement system for a substrate is provided, wherein the optical axis direction of the image capturing device is perpendicular to the plane of the substrate. In the circuit measurement system for substrates described in claim 4 of the patent application, the first light source includes a coaxial light source; and the second light source includes a lateral light source. As in the circuit measurement system for substrates described in item 5 of the patent application, the coaxial light source is disposed in the optical axis direction of the image capture device, and the lateral light source is arranged around the periphery of the coaxial light source. As described in item 1 of the patent application, the circuit measurement system for substrates, wherein the optical axis direction of the image capture device and the plane of the substrate present a shooting angle, and the shooting angle is between 0 degrees and 90 degrees. between. As claimed in claim 7 of the patent application, the circuit measurement system for substrates, wherein the first light source includes a coaxial light source, or a forward light source relative to the plane of the substrate; wherein the second light source includes one side towards the light source. As described in item 8 of the patent application, the circuit measurement system for substrates, wherein the imaging angle between the optical axis direction of the image capturing device and the light output direction of the forward light source is between 20 degrees and 40 degrees; the image capture device The angle between the optical axis direction of the device and the light output direction of the side light source is between 30 degrees and 50 degrees. As described in item 1 of the patent application, the circuit measurement system for substrates, wherein the first light source or the second light source includes one of red, green, and blue light sources; wherein the first light source and the third light source The colors of the two light sources are different. A circuit measurement system for a substrate, including: a first light source group that provides a first color beam and a second color beam to the substrate to display a first circuit image feature of the substrate; a first image A capture device is disposed on the top view direction side of the substrate to capture the first line image characteristics; a second light source group provides the first color light beam and the second color light beam to the substrate to display A second line image feature of the substrate; a second image capture device disposed on the side view direction side of the substrate to capture the second line image feature; and an image processing device to analyze the first line Image features and the second line image characteristics are used to obtain line information, which includes line upper width, line lower width, side wall area width, side wall area area, or/and side wall area surface quality. The circuit measurement system for substrates as described in Item 11 of the patent application system, wherein the first line image feature or the second line image feature includes a first area feature displayed by providing the first color light beam to the substrate, and a second area feature displayed by providing the second color light beam to the substrate. , and mixing the first color light beam and the second color light beam to the third area feature displayed on the substrate. As claimed in claim 12 of the patent application, the circuit measurement system for substrates, wherein the first area features include image features on the upper plane of the circuit or the bottom plane of the substrate; wherein the second area features include circuit side walls The third area feature includes the image feature at the junction of the upper plane of the circuit and the circuit sidewall, or the image feature at the junction of the bottom plane of the substrate and the circuit sidewall. As claimed in item 11 of the patent application, the circuit measurement system for substrates, wherein the optical axis direction of the first image capturing device is perpendicular to the plane of the substrate. As claimed in item 14 of the patent application, the circuit measurement system for substrates, wherein the first light source group includes a coaxial light source and a lateral light source, and the coaxial light source is disposed in the direction of the optical axis of the image capture device , the lateral light source system ring is arranged on the periphery of the coaxial light source. As described in item 11 of the patent application, the circuit measurement system for substrates, wherein the optical axis direction of the second image capturing device is in line with the plane of the substrate Presents a shooting angle between 0 degrees and 90 degrees. As claimed in claim 16 of the patent application, the circuit measurement system for substrates, wherein the second light source group includes a coaxial light source or a forward light source relative to the plane of the substrate, and a lateral light source. As described in item 17 of the patent application, the circuit measurement system for substrates, wherein the imaging angle between the optical axis direction of the second image capturing device and the light output direction of the forward light source is between 20 degrees to 40 degrees; the angle between the optical axis direction of the second image capturing device and the light output direction of the side light source is between 30 degrees and 50 degrees. As described in item 17 of the patent application, the circuit measurement system for substrates, wherein the coaxial light source or the forward light source includes one of red, green, and blue light sources; wherein the coaxial light source and the forward light source The colors are different. As in the circuit measurement system for a substrate described in item 11 of the patent application, the image processing device obtains the circuit thickness, circuit cross-sectional area or circuit volume of the substrate based on the circuit information. As described in item 20 of the patent application, the circuit measurement system for substrates, wherein the image processing device obtains the substrate based on the circuit cross-sectional area. The circuit carrying capacity of the board (Current-Carry Capacity). As described in item 11 of the patent application, in the circuit measurement system for a substrate, the image processing device obtains a three-dimensional image of the circuit of the substrate based on a stereoscopic vision method. As described in item 11 of the patent application, the circuit measurement system for a substrate, wherein the circuit information further includes circuit defect information of the substrate.

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