KR102684837B1 - Wire measuring system and method for board inspection - Google Patents

Abstract

The present invention provides a circuit measurement system applied to a substrate, and 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 the substrate to represent a first area characteristic of the substrate. The second light source provides a second color light flux to the substrate to reveal a second regional feature of the substrate. The image capture device takes an image from the substrate and obtains the first area feature and the second area feature. The image processing device is connected to the image capture device and acquires circuit information by analyzing the first region characteristics and the second region characteristics.

Description

Circuit measurement system and method applied to boards {WIRE MEASURING SYSTEM AND METHOD FOR BOARD INSPECTION}

The present invention relates to a circuit measurement system and method, and particularly to a circuit measurement system and method applied to a board that improves circuit contrast through a multicolor light source.

With the development of fully automated industry, Automatic Optical Inspection (AOI) has already been widely applied to visual inspection of circuit board assembly production lines in the electronics industry, replacing the traditional artificial visual inspection task. did.

The automatic optical recognition system is a common and representative means in the industrial manufacturing process. It mainly uses a camera device to photograph the surface condition of the material to be measured and inspects defects such as foreign substances or pattern abnormalities using computer image processing technology. Since contact inspection is adopted, it can be used to inspect semi-finished products in the production line process.

In general, the basic principle of the optical recognition system is to use imaging technology to compare whether there is a difference between the object to be measured and the reference image and determine whether the object to be measured meets the standard. Therefore, whether the automatic optical recognition system is good or bad is determined. It is basically determined by the resolution, imaging ability, and image recognition technology of the camera device.

As circuit signal frequencies are increasing day by day and circuit board circuits are becoming more detailed day by day, the cross-sectional area consistency of the circuit board circuit is more important for the image of circuit characteristics such as resistance and impedance, and even slight variations do not prevent the final electrical performance from reaching the expected performance. Do not allow it.

Conventional circuit inspection of circuit boards mainly uses black-and-white cameras and diffused light sources, making it difficult to recognize the upper and lower circuit widths. In particular, when the upper width edge is provided with an arched corner, the distinction becomes especially difficult, making measurement of the circuit width difficult. This is inaccurate and causes the problem of inaccurate circuit cross-sectional area calculations.

In addition, in the 3D inspection of conventional circuits, confocal microscopy, triangular reflection technology, and white light interference technology are mainly used, all of which build a 3D model by point measurement, and the measurement Not only is the time excessively slow, mass detection is difficult, and due to limitations in point measurement, only local height information can be obtained, and it is difficult to combine it into complete circuit cross-section information.

The main object of the present invention is to provide a circuit measurement system applied to a substrate, and 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 the substrate to represent a first area characteristic of the substrate. The second light source provides a second color light beam to the substrate to reveal a second area characteristic of the substrate. The image capture device takes an image from the substrate and obtains the first area feature and the second area feature. The image processing device is connected to the image capture device and acquires circuit information by analyzing the first region characteristics and the second region characteristics.

Another object of the present invention is to provide a circuit measurement system applied to a substrate, and includes a first light source group, a first image capture device, a second light source group, a second image capture device, and an image processing device. The first light source group provides a first color light flux and a second color light flux to the substrate to represent a first circuit image feature of the substrate. The first image capture device is provided on the upper side of the substrate and adopts the first circuit image feature. The second light source group provides a first color light flux and a second color light flux to the substrate to represent a second circuit image feature of the substrate. The second image capture device is provided on a lateral side of the substrate and adopts the second circuit image feature. The image processing device acquires first circuit information by analyzing the first circuit image feature and the second circuit image feature.

Therefore, the present invention can effectively increase image contrast between a plurality of feature areas on a circuit, thereby improving circuit measurement accuracy and further increasing detection accuracy. In addition, the present invention highlights the R-angle image between feature area boundaries through the effect of double color light mixing, so that the boundaries between a plurality of feature areas can be effectively extracted and the data of each item of the circuit can be accurately measured. In addition, in addition to improving the contrast between feature areas, the present invention can highlight defects due to uneven defects on the circuit surface because the performance of colors in different angular planes is different, thereby increasing detection accuracy.

1 is a block schematic diagram of the circuit measurement system of the present invention.
Figure 2 is a block schematic diagram of a first embodiment of the present invention.
Figure 3 is a block schematic diagram of a second embodiment of the present invention.
Figure 4 is a process schematic diagram (a) of the circuit detection method of the present invention.
5 is a schematic diagram of the circuit board.
Figure 6 is a schematic diagram of the division of the region of interest of the present invention.
Figure 7 is a block schematic diagram of a third embodiment of the present invention.
Figure 8 is a cross-sectional schematic diagram of the substrate circuit.
Figure 9 is a three-dimensional image schematic diagram of the board circuit in the present invention.
Figure 10 is a coordinate positioning diagram related to the substrate circuit.
11 is a schematic diagram of a bird's-eye view of a circuit board.
12 is a side view schematic diagram of the board circuit.
Figure 13 is a three-dimensional imaging schematic diagram (a) of the circuit measurement system of the present invention.
Figure 14 is a three-dimensional imaging schematic diagram (b) of the circuit measurement system of the present invention.
Figure 15 is a three-dimensional imaging schematic diagram (c) of the circuit measurement system of the present invention.
Figure 16 is a process schematic diagram (b) of the circuit detection method of the present invention.

The detailed description and technical content regarding the present invention are described below in conjunction with the drawings. In addition, for convenience of explanation, the drawings of the present invention may not be drawn to actual proportions, and the drawings and their proportions do not limit the scope of the present invention.

To help understand the main technical concept of the present invention, first, a detailed description of the main structure of the present invention will be provided. Referring to Figure 1, Figure 1 is a block schematic diagram of the circuit measurement system of the present invention. The circuit measurement system 100 of this embodiment mainly includes an image capture device 10, a first light source 20, a second light source 30, and an image processing device 40.

The image capture device 10 acquires a substrate image by using the substrate Ob as the image. The image capture device 10 includes, but is not limited to, a color camera, and photographs the substrate Ob in the detection area IA. Here, the corresponding substrate Ob includes at least one substrate circuit. In one embodiment, the image capture device 10 may be an area scan camera or a line scan camera.

The first light source 20 provides a first color light flux to the corresponding substrate Ob to display the first area characteristic of the corresponding substrate circuit. A preferred embodiment of the first color light flux may be a basic color group light source such as red light, green light, or blue light, and in addition to the light source of the color group, the first color light flux may be may be a light source of another different color, but the present invention is not limited thereto. The first light source 20 is disposed above the detection area IA and aims at the circuit of the substrate Ob at a first angle. The first light source 20 is output to the substrate circuit through a specific irradiation angle, so that the image capture device 10 selects a substrate image at a corresponding position to exhibit high contrast, and the captured substrate image is one at a specific angle on the substrate. Make the sides stand out. The first area feature includes an image feature on the circuit top width plane or the corresponding substrate bottom plane.

The second light source 30 provides a second color light flux to the corresponding substrate to display the characteristics of the second area of the substrate. A preferred embodiment of the second color light flux may be a basic color group light source such as red light, green light, or blue light, and in addition to the light source of the color group, the second color light flux may be may be a light source of another different color, but the present invention is not limited thereto. The second light source 30 is disposed on one side of the detection area (IA) and aims at the board circuit of the board (Ob) at a second angle. The second area features include image features on the circuit sidewall.

The luminous flux color output by the second light source 30 is different from the luminous flux color output by the first light source 20, and the color performance between different areas can be improved through the luminous flux performance of different colors, thereby creating a structural edge texture. highlights.

The angle and color irradiated by the second light source 30 are different from those of the first light source 20, and therefore, the area (e.g., first area feature) where the first light source 20 is highlighted on the corresponding substrate is the first light source 20. 2 The light source 30 is different from the highlighted area (e.g., second area feature) on the corresponding substrate, and thus, in the image of the corresponding substrate circuit, the relative angle with the first light source 20 and the second light source 30 Different colors appear between different areas, and machine vision is advantageous in distinguishing areas of interest.

In addition, the third region feature is included in the circuit image of the corresponding substrate Ob and displayed on the corresponding substrate through the light beam in which the first color and the second color are mixed. For example, the mixed light effect is generated at the position of the flip angle/R angle (for example, the R angle between the plane and the plane connection position) of the board circuit, and the image at the R angle position is projected onto the other plane through the mixed light effect. It is made to stand out relative to the area of , so that the mixed color area can be easily led through machine vision as the area of interest or the border of the image. The third region feature includes an image feature of the boundary position between the circuit top width plane and the circuit sidewall, or an image feature of the boundary position of the bottom plane of the substrate and the circuit sidewall.

The image capture device 10 captures the first region feature, second region feature, and third region feature through the first color beam and the second color beam in the substrate image captured after the image adopts the corresponding substrate Ob. Create.

The image processing device 40 is connected to the image capture device 10 and acquires the substrate image selected by the image capture device 10, and through the substrate image, the first region feature, the second region feature, and The third area feature is acquired, and the first area feature, the second area feature, and the third area feature are analyzed to obtain circuit information. Specifically, the image processing device 40 may store or access an image analysis program through a memory unit (not shown) loaded by the processor, and may perform an image analysis function through the program. Specifically, image analysis programs include, for example, image preprocessing programs, image segmentation and positioning, defect measurement (gradientization, region growth, growth compensation, etc.), machine learning systems, and deep learning systems. etc., and the present invention is not limited thereto.

In a possible embodiment, the image capture device 10 includes a filter (which may be a physical filter or a software filter) that filters light sources different from the first light source and the second light source, and in this way Image noise generated by environmental light sources can be reduced, further increasing detection efficacy.

Referring together to Figure 2, Figure 2 is a block schematic diagram of a first embodiment of the present invention. The circuit measurement system 200 of this embodiment enhances the contrast of structural features in the substrate image through a specific optical structure. The circuit measurement system 200 includes an image capture 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 capture device is perpendicular to the plane of the corresponding substrate (as shown in FIG. 2, the optical axis direction of the image capture device 10A is arrow A1 and the substrate plane F2). .

In this embodiment, the disposed first light source 20A includes a co-axial light source provided in the capturing direction of the image capture device. The light output direction generally coincides with the optical axis direction of the image capture device 10A, and therefore, the coaxial light output from the first light source 20A is reflected on a surface perpendicular to the optical axis direction and is captured by the image capture device 10A. ) enters the lens, and therefore, the brightness of the first color is increased in the circuit top width plane (US) and the substrate bottom plane (BS) in the substrate image, so that the circuit top width plane (US) (and the substrate bottom plane) in the substrate image (BS)) and the circuit side wall (SS).

In this embodiment, the disposed second light source 30A includes a lateral light source that provides lateral illumination to the substrate Ob. In a possible embodiment, the lateral light source surrounds the perimeter of the coaxial light source and provides a lateral light source (for example an annular light source) to the object to be measured. In general, the side wall of the board circuit is basically an inclined surface with a certain inclination angle, the lateral light source fills the light against the side wall of the board circuit in the lateral direction, and the annular light source and the board circuit maintain an appropriate distance. In , the lateral light source (second light source 30A) increases the brightness of the second color of the sidewall of the circuit. Based on the optical combination, a clear color difference is generated in the substrate image between the circuit top width plane (US) and the circuit side wall (SS) of the substrate circuit. In embodiments of the annular light, the annular light may provide a specific angle of light to an object to be measured (e.g., through a light guide, optical fiber, reflective lens, refractive lens, or other optical element), thereby providing a lateral light source. Adjust the angle.

At the structure boundary position, the circuit illuminated by the coaxial light source and the lateral light source includes image features (R angle boundary C1) at the boundary position of the circuit top width plane (US) and the circuit sidewall (SS), and the substrate bottom plane. A mixed light effect occurs at the image feature (R angle boundary (C2)) at the boundary position between (BS) and the circuit side wall (SS), and through the mixed light effect, the image of the R angle boundary (C1, C2) is projected onto the circuit width plane ( US), the position relative to the circuit sidewall (SS) and the board bottom plane (BS) is highlighted, and the boundary can be easily divided by machine vision as a region of interest or image boundary.

In a preferred embodiment, in order to prevent the light source from interfering with the substrate imaging of the image capture device 10A, the co-axial light source is provided in the optical axis direction of the image capture device 10A, and the lateral light source is provided along the co-axial light source. It is provided by surrounding the outer location of the light source.

In a possible embodiment, the image capture device 10A includes a filter (which may be a physical filter or a software filter), which filters light sources different from the first light source 20A and the second light source 30A. In addition, through this method, the influence of image noise generated by environmental light sources on the substrate image can be reduced, further increasing detection efficiency.

Among the board images, different colors are reflected between the circuit top width plane (US) of the board circuit and the circuit side wall (SS), and therefore, at this time, a second filter (which may be a physical filter or a software filter) is further provided to separate areas of different colors. are each shielded to facilitate division of the region of interest of the image processing device 40A, and further circuit information can be obtained through the image after division. For example, when the coaxial light source is a red light source (Red) and the lateral light source is a green light source (Green), a red filter can be used to indicate the sidewall area in the substrate image, and a green filter can be used to indicate the sidewall area in the substrate image. It can represent the circuit upper width plane area of .

Hereinafter, another possible embodiment of the present invention will be described. Referring to FIG. 3, FIG. 3 is a block schematic diagram of a second embodiment of the present invention. The circuit measurement system 300 of this embodiment has a different optical structure, and can similarly achieve the effect of increasing the contrast of structural features of the substrate image. The circuit measurement system 300 includes an image capture 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 capture device 10B and the substrate plane F2 represent an imaging angle, and in a possible implementation manner, the imaging angle is preferably between 0 degrees and 90 degrees. and the change in angle is not limited by the present invention.

In this embodiment, the disposed first light source 20B includes a co-axial light source, or a forward light source relative to the plane of the substrate. The co-axial light source or the forward light source faces the upper side of the relevant board circuit, outputs light to the relevant board (Ob), and provides a light source on the upper side to determine the circuit top width plane (US) and the board bottom among the board images. By increasing the brightness of the first color of the subplane (BS), the first color has a relatively high contrast between the circuit top width plane (US) (and the substrate bottom plane (BS)) and the circuit sidewall (SS) in the substrate image. Let's do it.

The disposed second light source 30B includes a lateral light source in this embodiment, and the lateral light source preferably includes a light guide that improves the directivity of the light source and provides lateral light to the substrate Ob. The lateral light source controls the board circuit in the lateral direction, and increases the brightness of the second color of the circuit sidewall in the board image through the inclined directional light source to show the circuit sidewall (SS) and the circuit upper width plane (US) in the board image ( and the substrate bottom plane (BS)) so that the second color has a relatively high contrast.

At the structure boundary position, the circuit illuminated by the coaxial light source (or forward light source) and the lateral light source includes image features (R angle boundary (C1)) at the boundary position of the circuit upper width plane (US) and the circuit side wall (SS); And the mixed light effect is generated at the image feature (R-angle boundary (C2)) at the boundary between the substrate bottom plane (BS) and the circuit side wall (SS), and the image of the R-angle boundary (C1, C2) is generated through the mixed light effect. This makes the position relative to the circuit top width plane (US), circuit sidewall (SS), and board bottom plane (BS) highlighted, and the boundary can be easily divided by machine vision as a region of interest or image boundary.

The optical arrangement relationship between the image capture device 10B and the first light source 20B and the second light source 30B is mainly determined by the included angle between the circuit sidewall of the substrate circuit and the circuit top width plane, and the circuit structure is manufactured. When adjustments are made due to process or demand, the narrow angle relationship between each device can also be adjusted accordingly. In a preferred embodiment, the taking angle α between the optical axis direction (arrow A2) of the image capture device 10B and the light output direction A3 of the coaxial light source (or forward light source) is 20 degrees to 40 degrees. is between degrees; The included angle (β) between the optical axis direction (arrow (A2)) of the image capture device (10B) and the light output direction (A4) of the corresponding lateral light source is 30 to 50 degrees, and the angle varies up and down depending on the actual situation. It can be finely adjusted, and the output intensity of the first light source 20B and the second light source 30B can also be adjusted according to actual demand.

To increase the computational efficiency and accuracy of the image processing device 40B, in a possible embodiment, the image capture device 10B includes a filter (which may be a physical filter or a software filter), where the filter has a red color (Red filter). ), Green, and Blue. Among the three color light sources, light sources of different colors from the first and second light sources are filtered, and through this method, the influence of environmental light sources on the substrate image can be reduced. This further increases detection efficacy.

Through the above-described light source arrangement, among the board images, the images of the circuit top width plane (US), board bottom plane (BS), and circuit side wall (SS) each highlight two different color performances, and at this time, the filter (real filter or software) highlights two different color performances. By providing a fill layer (which may be a fill layer), each area of a different color is shielded to facilitate division of the region of interest for the image processing device 40B, and circuit information is obtained from the image after division. For example, when the coaxial light source is a red light source (Red) and the lateral light source is a green light source (Green), a red filter can be used to represent the sidewall area (SS) in the substrate image, and a green filter can be used to indicate the sidewall area (SS) in the substrate image. The circuit top width plane area (US) and the substrate bottom plane (BS) in the substrate image can be indicated.

Above, a detailed description of the hardware device of the present invention has been provided, and a relatively detailed description of the cooperative work performed by the hardware and the software program portion will be continued below. First, referring to FIG. 4, before shooting, the first light source 20 of the first color and the second light source 30 of the second color are provided to the substrate circuit of the substrate to determine the first area characteristics and the second color of the substrate circuit. The second area feature is displayed (step S101). Specifically, the first light source 20 and the second light source 30 simultaneously provide a first color light flux and a second color light flux to the substrate surface, and the circuit image width plane US (US) of the substrate circuit in the image with different colors, respectively. The substrate bottom plane (BS)) and circuit sidewall (SS) are shown. At this stage, the individual output power of the two groups of lights (the first light source 20 and the second light source 30) is calibrated according to the method of machine vision or visual inspection, and the circuit upper width plane (US) (substrate bottom plane (BS)) and circuit side wall (SS) images can be further highlighted.

After confirming the completion of the output arrangement of the light source, the substrate is photographed through the image capture device 10 and an image of the substrate is obtained (step S102). Here, the image capture device 10 may be a camera device that shoots from a fixed point, or may be a camera device that is combined with a mobile platform to perform multi-point local shooting or route-type shooting along a circuit, and the present invention There is no limitation to this.

After completion of imaging, the image processing device 40 acquires a board image and circuit information from the board image (step S103). Specifically, in this step, the image processing device 40 analyzes circuit information in the substrate image through an image analysis algorithm. Here, the circuit information may be 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 mass of the sidewall area, or the size, shape, curvature, angle, and surface of each area of the circuit. It may be a visible defect such as a defect, or a visible defect that is difficult to recognize with the naked eye under a general light source, and the present invention is not limited thereto. Under normal circumstances, after the board circuit is formed in the manufacturing process, the cross-sectional shape generally exhibits a trapezoid, and depending on the actual situation, the cross-sectional shape of the board circuit may be rectangular. A board representing a trapezoid in a circuit can be chosen to be imaged either at a bird's-eye angle or at a lateral angle (oblique direction from above); In a circuit, a rectangular substrate may be preferably imaged at a lateral angle to facilitate the acquisition of sidewall images.

For convenience of explanation, the present invention is described in a circuit shape with a normal trapezoidal cross-section, and the board image obtained by shooting by the image capture device 10 (as shown in FIG. 5) is mainly the upper side of the board circuit. circuit upper width flat area (R1), circuit side wall areas (R2, R3) provided on both sides of the circuit upper width flat area (R1), substrate bottom flat area (R4) outside the circuit side wall areas (R2, R3), circuit R-angle area (CE1) between the upper-width flat area (R1) and the circuit sidewall area (R2), R-angle area (CE2) between the upper-width flat area (R1) and the circuit sidewall area (R3), and circuit sidewall area (R2) ) and the R angle area (CE3) at the connection position of the substrate bottom flat area (R4), and the R angle area (CE4) at the connection position between the circuit side wall area (R3) and the substrate bottom flat area (R4). . The circuit top width flat area (R1), the circuit side wall areas (R2, R3), and the substrate bottom flat area (R4) have a clear difference in color through the optical arrangement of the first light source 10 and the second light source 20. occurs. In addition, through the mixed light effect, the R angle regions (CE1, CE2) between the circuit top width plane region (R1) and the circuit sidewall region (R3), and the circuit sidewall regions (R2, R3) and the substrate bottom plane region (R4) ), the R angle region (CE3, CE4) between them forms a color band whose color is different from the circuit top width plane region (R1), the circuit side wall region (R2, R3), and the substrate bottom plane region (R4) due to the mixed light effect. do. The color band formed by each R region (CE1, CE2, CE3, CE4) is a prominent boundary that can be referenced in the image and is advantageous for image segmentation processing.

The image processing device 40 sets a filter according to the image, and further sets a threshold (e.g., binary processing) to easily divide the image of the two regions of interest (as shown in FIG. 6). ), the image (I1) is an image of the circuit top width plane area (R1) of the divided board circuit, and the image (I2) is an image of the side wall areas (R2, R3) of the divided board circuit, and the two groups of segments in the image are By measuring the width, circuit information such as the circuit top width (UW1), the first side sidewall area width (SW1), and the second side sidewall area width (SW2) can be obtained. The color band formed by each R area (CE1, CE2, CE3, CE4) can have a certain width, and therefore, when calculating the data for each item of the circuit, each R area (CE1 , CE2, CE3, CE4), the width of the circuit top width (UW1), the first side wall area width (SW1), and the second side wall area width (SW2) that approach the actual value can be modified and obtained. You can.

The image after being divided through the image processing device 40 can be corrected for errors through the pixel width, Camel's internal parameters, and shooting angle. The size of each area in the image is further calculated, and the circuit information for each section of the board is calculated. You can get more. In addition to analyzing the boundary of the board circuit in the image, the obtained image can be used to re-examine defects; If a board circuit defect (e.g. missing copper, uneven surface, ink, etc.) appears in a different color in the image due to a different texture color or irregular surface in the adopted image, the color masking and thresholding procedure previously performed During the setting process, corresponding defect features also appear, and the image processing device 40 can implement a defect detection function based on the image of the board circuit by displaying the position of the defect.

In addition to the above embodiment, the present invention can also obtain a three-dimensional image of a board circuit by acquiring circuit information for each item in the image. Referring to Figure 7, Figure 7 is a block schematic diagram of a third embodiment of the present invention. This embodiment is similar to the above embodiments, and therefore description of the same parts is omitted.

The circuit 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 corresponding first image capture device 10C. It includes an image processing device 50C connected or coupled to an image capture device 10C and a corresponding second image capture device 20C.

In this embodiment, the first image capture device 10C is provided on the bottom side of the board Ob, and captures the detection area IA1 and obtains a bird's-eye view of the first circuit on the board Ob. The first circuit video feature is adopted. The bottom direction refers to a position above the plane of the substrate, and the optical axis direction of the first image capture device 10C is generally perpendicular to the plane of the substrate. The combination of the first image capture device 10C and the first light source group 30C is, for example, the same as the arrangement of the first embodiment, and the first light source group 30C includes the co-axial light source 31C and comprising a lateral light source 32C; The co-axial light source 31C is provided in the capturing direction of the image capture device 10C, and the lateral light source 32C is provided surrounding the outer edges of the co-axial light source 31C. The first image circuit feature is a first area feature indicated by providing a first color light flux (co-axial light source 31C) to the substrate, and a second color light flux (lateral light source 32C) is provided to the substrate. It includes a second area characteristic represented by the substrate, and a third area characteristic represented by the substrate by mixing the first color light flux and the second color light flux.

In this embodiment, the second image capture device 20C is provided on the lateral side of the board Ob, and captures the detection area IA2 and acquires a side image of the second circuit on the board Ob. Adopt the second circuit video feature. In this embodiment, the optical axis direction of the second image capture device 20C and the substrate plane represent the capturing angle, and the capturing angle is between 0 degrees and 90 degrees. Here, the lateral side indicates maintaining an appropriate inclination angle with the circuit at a forward position or an upwardly inclined position at the boundaries of both sides of the circuit board. The combination of the second image capture device 20C and the second light source group 40C may be, for example, the same as the arrangement of the second embodiment, and the second light source group 40C includes the co-axial light source 41C ( or a forward light source relative to the plane of the substrate), and a lateral light source 42C; The taking angle between the optical axis direction of the second capture device 20C and the optical output direction of the forward light source is between 20 degrees and 40 degrees; The included angle between the optical axis direction of the second image capture device 20C and the optical output direction of the lateral light source 42C is 30 to 50 degrees. The second image circuit feature is a first area feature indicated by providing a first color light flux (co-axial light source 41C) to the substrate, and a second color light flux (lateral light source 42C) is provided to the substrate. It includes a second area characteristic represented by the substrate, and a third area characteristic represented by the substrate by mixing the first color light flux and the second color light flux.

In the present invention, the first image capture device 10C and the second image capture device 20C can simultaneously provide four light sources to the board circuit and simultaneously capture images of the board circuit. In another possible embodiment, a method of time-sharing shooting and light source provision, for example, in a program, selects the first group image as a combination of the first image capture device 10C and the first light source group 30C. do; In another program, a second group of images is adopted by combining the second image capture device (20C) and the second light source group (40C), and two groups of images can be obtained by distinguishing the shooting time. Changes to the embodiments do not fall within the scope of the present invention.

In another possible embodiment, the first image capture device 10C, the second image capture device 20C, the first light source group 30C, and the second light source group 40C are provided jointly on the same platform, The relative positions and relative angles between devices can be kept fixed, and the circuit characteristics at each position can be confirmed by establishing a correlation between the recorded platform movement values and the captured images. In another possible embodiment, the first image capture device 10C, the second image capture device 20C, the first light source group 30C, and the second light source group 40C are jointly provided on the same platform. In, the first optical combination of the first image capture device 10C and the first light source group 30C and the second optical combination of the second image capture device 20C and the second light source group are forward and backward at the position of the platform. It is arranged so that the paths taken by the first image capture device 10C and the second image capture device 20C match (arrive first and then later), thereby increasing detection efficiency and coordinate positioning accuracy.

The co-axial 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 is different from any of the red, green, and blue light sources. Contains a colored light source. The co-axial 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 lateral light source 42C includes any of red, green, and blue light sources. It includes a light source of a different color from the co-axial light source 41C (or forward light source).

The image processing device 50C is connected or coupled to the first image capture device 10C and the second image capture device 20C to obtain a bird's eye view image and a side image of the substrate, and the bird's eye view image and the side image. The first circuit image feature and the second circuit image feature are acquired and analyzed, and circuit information of the corresponding board is obtained through the first circuit image feature and the second circuit image feature. The image processing device 50C determines the circuit upper width and the circuit lower width of the circuit through the bird's-eye view image (i.e., the circuit upper width at the same cross-sectional position plus the first side wall area width and the second side side wall area width). Circuit information such as (the total sum of), sidewall area width, sidewall area area, or/and sidewall area surface mass is acquired, and circuit information of the sidewall perspective width of the corresponding board circuit is obtained through the bird's eye view image. According to the circuit information, the circuit thickness value of the circuit can be calculated through the lens shooting angle, the upper line width of the circuit, the total area width, and/or the obtained sidewall isometric width, and the calculation method of the height value is based on the Pythagorean theorem. It can be estimated through this, and is explained again below.

Next, referring to FIG. 8, FIG. 8 is a cross-sectional schematic diagram (b) of the substrate. The image processing device 50C acquires the upper circuit width (W1), the lower circuit width (W2), and the sidewall isometric width (W3) from the image, and then further obtains the substrate circuit thickness (H) through Pythagorean operation. You can; In a situation where the optical axis direction of the camera and the circuit sidewall area of the circuit are orthogonal (the sidewall projection length through which the sidewall enters the camera is equal to the sidewall actual length), the sidewall isometric width (W3) can be calculated and obtained according to the direct distance mixing ratio. The circuit thickness (H) can be obtained through the sidewall isometric width (W3); In a situation where the optical axis direction of the image capture device and the sidewall area of the circuit are non-orthogonal, the actual sidewall isometric width (W3) is obtained by considering the shooting angle correction of the image capture device, and the circuit thickness (W3) is obtained through the sidewall isometric width (W3). H) can be obtained, or the circuit thickness (H) can be obtained by direct alternative calculation through the sidewall depression width (S1), the shooting angle, and the sidewall projection length obtained by shooting from the corresponding time, and the present invention relates to this. It is not limited.

In another embodiment, when checking the circuit top width W1, the image processing device 50C may check the sidewall depression width S1 through the circuit top width plane US and the circuit sidewall SS boundary. Through the Pythagorean theorem, the circuit thickness (H), sidewall isometric width (W3), and sidewall relief width (S1) correspond to the formula below: . Since the sidewall perspective width (W3) and the sidewall depression width (S1) are known values, the circuit thickness (H) can be obtained through calculation. In a situation where the circuit thickness (H) is obtained, the circuit cross-sectional area (A) of the corresponding segment can be calculated and obtained through the trapezoidal formula, and the calculation formula is as follows: . After obtaining the cross-sectional area, the image processing device 70C can obtain the circuit carrying capacity (Current-Carry Capacity) on the corresponding substrate by the corresponding circuit cross-sectional area; The corresponding circuit capacity can be obtained through the following equation: , where I is the maximum current carrying capacity, k is the correction factor, is the maximum temperature difference, and A is the cross-sectional area of the circuit. In addition, it is possible to find defects in the circuit using image recognition in the captured overhead images and side images and obtain information on the defects in the circuit.

The circuit cross-sectional shape is exemplified as a trapezoid, but may also be a rectangle or other shape, and is not limited thereto. In addition, the current acceptance formula may refer to other sources such as IPC-2221 in addition to the above formula, and may be a calculation formula that complies with related standards such as IPC. In another possible embodiment, the image processing device 50C may obtain circuit current capacity by searching a look up table using a search method. In the lookup table, values that do not appear in the lookup table can be calculated using the K-Nearest Neighbor or Insertion Method, which is determined depending on the needs of the design.

Referring to FIG. 9, FIG. 9 is a three-dimensional image schematic diagram of a board circuit. In a preferred embodiment, the image processing device 70C acquires the target segment root (L) of the substrate circuit through the substrate image, and determines the upper width of the circuit (W1), the lower width of the circuit (W2), and the corresponding sidewall. According to the perspective width W3 and the target segment root L, the circuit volume of the target segment root L can be obtained through the circuit cross-sectional area and the segment root. In another possible embodiment, after obtaining a plurality of cross-sectional areas, the circuit volume of the target segment root (L) may be obtained by multiplying the segment cross-sectional area on each cross-section by the corresponding segment length.

In addition to the technical features for analyzing circuit information, the circuit information obtained by the present invention can construct a three-dimensional image of the circuit through a stereo vision algorithm.

Below, a description will be given of the method of forming a three-dimensional image of a board circuit in the present invention. Referring to FIGS. 10 to 15, FIGS. 10 to 15 are coordinate positioning diagrams of the board circuit and a schematic diagram of an overhead image of the board circuit. , side image schematic diagram of the circuit board circuit, three-dimensional image imaging schematic diagram of the circuit measurement system of the present invention (a), three-dimensional image imaging schematic diagram of the circuit measurement system of the present invention (b), three-dimensional image diagram of the circuit measurement system of the present invention This is an imaging schematic diagram (c).

First, referring to FIG. 10, the image processing device 50 receives a bird's-eye image and a side image of the corresponding board circuit, and then selects a plurality of consecutive coordinate positions (M ₁ )( ₁ , Y ₂ , Z ₃ )...M _n (X _n , Y _{n ,} Z _n )... _{M N (} Through the algorithm (Stereo Vision Algorithm), the image pixel coordinate system (u, v) is converted to the world coordinate system (X _w , Y _w , Z _w ), and the positioning of the target coordinate location in the image is completed. In another possible embodiment, the plurality of coordinate positions may be sampled from the boundary, center line, or other easily recognized reference feature of the other side, but the present invention is not limited thereto. Additionally, in another possible embodiment, particularly in the embodiment of an online scan camera, the coordinate position may be feedback confirmed through data from the mobile load device.

Next, referring to FIG. 11 , after completing the setting of the corresponding coordinate position, the image processing device 50C acquires the circuit upper width W1 and the circuit lower width W2 from the overlook image. The relative position between the upper circuit width (W1) and the lower circuit width (W2) is determined by the value of the ratio of the sidewall depression widths (S1, S2) on both sides or the sidewall depression widths (S1, S2) on both sides in the bird's eye view image. You can obtain it accordingly.

Next, referring to FIG. 12 , the image processing device 50C receives a side image of the circuit and then analyzes the circuit perspective width W3 in the circuit image from the side image.

After going through the above two steps, the image processing device 50C obtains the circuit upper width (W1), the circuit lower width (W2), both side wall depression widths (S1, S2), and side wall isometric width (W3). When the circuit thickness (H) is calculated and obtained through the circuit information, the coordinate positions (M _n ) (X _n , Y _n , Z _n ) to which the corresponding parameters belong are recorded.

Next, referring to FIG. 13 together, the circuit upper width (W1), the circuit lower width (W2), the circuit thickness (H), and the corresponding coordinate positions (M _n ) (X _n , Y _n , Z _n ) When acquiring, the image processing device 50C constructs a target cross-sectional image based on the upper circuit width (W1), the lower circuit width (W2), and the circuit thickness (H). In this step, first, the relative positional relationship between the upper circuit width (W1) and the lower circuit width (W2) is confirmed through the side wall depression widths (S1, S2) on both sides, and the parameter condition of the circuit thickness (H) is confirmed. In this situation, the bottom length, top length, height, first inclined side, and second inclined side of the trapezoidal cross-section can be confirmed, the two-dimensional shape on the corresponding cross-sectional area is determined according to the parameters, and a two-dimensional image cross-sectional view (ST ₁₎ can be confirmed. ) can be further configured. Through the constructed two-dimensional image cross-section, the circuit information of the two-dimensional image cross-section can be confirmed, and circuit defect information can be obtained through the circuit information.

Lastly, referring to FIGS. 14 and 15 together, 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 the corresponding coordinate positions (M ₁ ) ( Sample the _two -dimensional image cross-section (ST _{1 -ST n} -ST _{N )} corresponding to _n , Z _n )??(M _N ) ( . After completing the image stack (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 )??( In _{M N ) (}

Through the 3D image of the circuit board after reduction, circuit defect information can be obtained through circuit information obtained by the shape of the cross section, and through this, the type and type of defect can be confirmed to improve the efficiency of visual inspection.

Below, a detailed description of the circuit measurement method of the present invention will be provided in conjunction with the drawings. Referring together to Figure 16, Figure 16 is a process schematic diagram (b) of the circuit measurement method of the present invention, as shown:

This embodiment provides a circuit measurement method, including 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 feature and the second circuit image feature of the substrate Ob (step S201).

Next, the first image capture device 10C is provided on the upper side of the substrate to capture the first circuit image feature of the substrate (step S202). Additionally, a second image capture device 20C is provided on the lateral side of the substrate to capture the second circuit image feature of the substrate (step S203).

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

In step S204, the time at which the first image capture device 10C and the second image capture device 20C photograph the substrate may not be performed in sequential order, and first, the time of the first image capture device 10C The first circuit image feature may be obtained by performing imaging, or the second circuit image feature may be obtained by first performing imaging with the second image capture device 20C, or may be performed simultaneously, and the present invention is not limited thereto. .

Next, an image processing device 50C is provided to receive the bird's eye view image and the side image, and generate circuit information on the board circuit according to the bird's eye view image and the side image (step S205). The circuit information of the corresponding board circuit may include the upper circuit width, the lower circuit width, the sidewall area width, the sidewall area area, and/or the sidewall area surface mass, etc., but the present invention is not limited thereto.

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

Finally, after obtaining the circuit cross-sectional area, the image processing device 50C acquires the circuit current capacity on the substrate Ob according to the circuit cross-sectional area (step s207).

In summary, the present invention can effectively increase image contrast between a plurality of feature areas on a circuit, thereby improving circuit measurement accuracy and further increasing detection accuracy. In addition, the present invention highlights the R-angle image between feature area boundaries through the effect of double color light mixing, so that the boundaries between a plurality of feature areas can be effectively extracted and the data of each item of the circuit can be accurately measured. In addition, in addition to improving the contrast between feature areas, the present invention can highlight defects due to uneven defects on the circuit surface because the performance of colors in different angular planes is different, thereby increasing detection accuracy.

Above, the present invention has been described in detail, and the above contents are only preferred embodiments of the present invention and should not be limited to the scope of practice of the present invention. In other words, all equivalent changes and modifications made within the scope of the application for the present invention must still fall within the scope of the present invention.

100: Circuit measurement system
10: Video capture device
20: first light source
30: second light source
40: image processing device
IA: Inspection area
Ob: substrate
200: circuit measurement system
10A: Video capture device
20A: first light source
30A: second light source
40A: Image processing unit
A1: arrow
F2: Substrate plane
300: Circuit measurement system
10B: Video capture device
20B: first light source
30B: second light source
40B: Image processing unit
A2: arrow
A3: Light output direction
A4: Light output direction
α: Taking angle
β: narrow angle
Step S101-Step S103
US: Circuit width plane
SS: circuit sidewall
BS: Board bottom plane
C1: R angle boundary
C2: R angle boundary
R1: circuit upper width plane area
R2: Circuit sidewall area
R3: Circuit sidewall area
R4: Plane area at the bottom of the board
CE1: R angle area
CE2: R angle area
CE3: R angle area
CE4: R angle area
I1: Video
I2: Video
UW1: Circuit width
UW2: Width of circuit down width
SW1: Width of first side wall area
SW2: Second side sidewall area width
400: Circuit measurement system
10C: First image capture device
20C: Second image capture device
30C: first light source group
31C: Coaxial light source
32C: Lateral light source
40C: Second light source group
41C: Coaxial light source
42C: Lateral light source
50C: Image processing unit
IA1: Inspection area
IA2: Inspection area
W1: Circuit width
W2: Width of circuit down width
W3: Sidewall isometric width
W4: Sidewall isometric width
H: circuit thickness
L: target segment root
S1: Side wall relief width
S2: Side wall relief width
ST ₁ -ST _N : 2D image cross-sectional view
Steps S201-S207

Claims (14)

a first light source that provides a first color light flux to the substrate to represent a first area characteristic of the substrate;
a second light source that provides a second color light flux to the substrate to represent a second region feature of the substrate;
an image capture device that acquires the first area feature and the second area feature by capturing an image from the substrate; and
An image processing device connected to the image capture device and acquiring circuit information by analyzing the first region characteristics and the second region characteristics;
The circuit image of the board captured by the image capture device includes a third area feature that appears by mixing light fluxes of the first color and the second color;
The first area feature includes an image feature on an upper plane of the circuit or a lower plane of the substrate;
the second area feature includes an imaging feature on a sidewall of the circuit;
The third region feature is a circuit measurement system applied to a substrate including an image feature of a boundary position between an upper width plane of the circuit and a sidewall of the circuit, or an image feature of a boundary position between a lower width plane of the substrate and a sidewall of the circuit. . According to paragraph 1,
The circuit information is a circuit measurement system applied to a substrate including a circuit top width, a circuit bottom width, a sidewall area width, a sidewall area area, and/or a sidewall area surface mass. delete According to paragraph 1,
A circuit measurement system applied to a substrate where the optical axis direction of the image capture device and the plane of the substrate represent an imaging angle, and the capturing angle is between 0 degrees and 90 degrees; and
the first light source comprises a co-axial light source, or a forward light source relative to the plane of the substrate; The second light source is a circuit measurement system applied to a substrate including a lateral light source. According to paragraph 4,
A taking angle between the optical axis direction of the image capture device and the light output direction of the forward light source is 20 degrees to 40 degrees; A circuit measurement system applied to a substrate in which the included angle between the optical axis direction of the image capture device and the light output direction of the lateral light source is 30 to 50 degrees. According to paragraph 1,
The first light source or the second light source is one of red light, green light, and blue light; A circuit measurement system in which the colors of the first light source and the second light source are applied to different substrates. a first light source group that provides a first color light flux and a second color light flux to the substrate to represent first circuit image characteristics of the substrate;
a first image capture device provided on an upper side of the substrate and adopting the first circuit image feature;
a second light source group that provides a first color light flux and a second color light flux to the substrate to represent a second circuit image feature of the substrate;
a second image capture device provided on a lateral side of the substrate and adopting the second circuit image feature; and
An image processing device configured to acquire first circuit information by analyzing the first circuit image feature and the second circuit image feature;
The first circuit image feature or the second circuit image feature may include a first area feature shown by the first color light flux, a second area feature shown by the second color light flux, and the first color light flux and the second color light flux. It includes third area features that appear by mixing;
The first area feature includes an image feature on an upper plane of the circuit or a lower plane of the substrate;
the second area feature includes an imaging feature on a sidewall of the circuit;
The third area feature includes an image feature of a boundary position between an upper width plane of the circuit and a sidewall of the circuit, or an image feature of a boundary position between a plane of the substrate and a sidewall of the circuit. delete In clause 7,
A circuit measurement system applied to a substrate where the optical axis direction of the second image capture device and the plane of the substrate indicate an imaging angle, and the capturing angle is between 0 degrees and 90 degrees; and
A circuit measurement system applied to a substrate, wherein the second group of light sources includes co-axial light sources, or forward and lateral light sources relative to the plane of the substrate. According to clause 9,
A taking angle between the optical axis direction of the second image capture device and the light output direction of the forward light source is 20 degrees to 40 degrees; A circuit measurement system applied to a substrate in which the included angle between the optical axis direction of the second image capture device and the light output direction of the lateral light source is 30 to 50 degrees. According to clause 9,
The coaxial light source or the forward light source is one of red light, green light, and blue light; A circuit measurement system in which the colors of the co-axial light source and the forward light source are applied to different substrates. In clause 7,
The circuit information is a circuit measurement system applied to a substrate including a circuit top width, a circuit bottom width, a sidewall area width, a sidewall area area, and/or a sidewall area surface mass. According to clause 12,
A circuit measurement system applied to a substrate, wherein the image processing device obtains circuit thickness, circuit cross-sectional area, or circuit volume of the substrate according to the circuit information. In clause 7,
A circuit measurement system applied to a board in which the circuit information further includes circuit defect information of the board.