JPS6145400B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic pattern inspection device for printed wiring boards, and particularly to a wiring pattern positioning device.

Various automatic pattern inspection devices have been proposed in order to inspect whether the wiring pattern on a printed wiring board has been formed as an original and correct pattern. A typical inspection principle for this automatic inspection is a pattern matching method. In this pattern matching method, in addition to the printed wiring board to be inspected, a standard wiring board with the same pattern as this printed wiring board is prepared, and the patterns of both are optically read and the patterns are compared to each other. A comparison is made to check whether the pattern on the printed wiring board to be inspected is correct or incorrect. During this inspection, it is necessary to mutually position both wiring boards. Conventionally, through holes were used to position both wiring boards relative to each other. That is, through holes are provided in both wiring boards for positioning during inspection, the through holes on both wiring boards are searched, and both wiring boards are automatically driven so that they are in the correct positional relationship. I was positioning. However, since this method uses through holes, there are various problems in terms of alignment accuracy and the like. The details will be explained below with reference to the drawings.

The structure of a general printed wiring board 1 is shown in FIGS. 1 and 2, with FIG. 1 being a plan view seen from the wiring surface 2, and FIG. 2 being a sectional view taken along line A-A'. In these figures, 4 and 5 are wiring patterns made of conductive foil such as copper, 6 is a through hole for electrical connection with the wiring surface 3 on the back, 7 is an insulating base material 13, 14 is a ground layer, Like the inner layer patterns 4 and 5 used as the power supply layer, it is made of conductive foil. 1st
The wiring pattern shown in the diagram is generally the first
It is formed by etching the pattern shown by solid lines (excluding thick lines) and cross lines in the figure using a photographic master plate (mask), transferring it as a resist pattern onto copper foil, and etching it. If the photographic original plate is scratched during this forming process, minute adhesion 8, minute chipping 9, or minute protrusion 10 will occur, and insufficient etching will cause the pattern to become thick 11, and excessive etching will cause the pattern to become thinner 12. If these defects exist, minute chips 9 and thinning 12 may cause the circuit resistance layer to decrease, current capacity may be reduced, and wires may be disconnected due to contact during printed wiring board handling, while minute adhesion 8, minute protrusions 10, and thickening 11 may cause short circuits in the circuit. , solder bridging occurs during soldering, etc., making it impossible to construct the correct wiring path originally intended for the printed wiring board. These defects must be accurately inspected without missing even the slightest defects, especially as high-density packaging is being carried out these days, and the pattern width is about 0.1 mm. , is no longer viable by visual inspection. Therefore, in order to perform such an inspection by a machine, as shown in FIG. After alignment, there is a method of capturing each wiring surface as an optical image and comparing and verifying the images. This conventional method will be explained below.

In Fig. 3, the same configurations are arranged on the left and right except for the electrical signal comparison and verification device 27, and the parts on the right that correspond to the parts on the left (printed wiring board side to be inspected) are given the same reference numerals. A dashi is attached.

Therefore, the functions and operations of the parts on the right side can be replaced by the descriptions on the right side by adding dashes to the symbols in the explanations by explaining the functions and operations of the parts on the left side, so the explanations on the left side will be representative.

First, the printed wiring board 1 is placed on the stage 31 so that the patterns to be compared and inspected on the printed wiring board 1 to be inspected and the printed wiring board 1' for comparison and verification can be aligned with each other. For example, the printed wiring board 1 is provided with a hole that serves as a guide at a predetermined position, and the stage 31 is provided with a pin 33 that serves as a guide at a position that corresponds to the guide hole of the printed wiring board 1. ing. The printed wiring board 1 is installed on the stage 31 by inserting the guide pins 33 into the guide holes of the printed wiring board 1. Suppose that the positions of the guide pins 33 and 33' of the stages 31 and 31' are determined in advance so that the mutual patterns of the printed wiring board 1 to be inspected and the printed wiring board 1' for comparison and verification can be comparatively inspected. If so, the wiring patterns of the printed wiring board inserted into the guide pins are aligned with each other by the guide holes. For example, after placing the printed wiring board 1 to be inspected at a predetermined position on the stage 31 and installing the printed wiring board 1' for comparison and verification at a predetermined position on the stage 31', the actual wiring pattern or , a pattern specially prepared for positioning is observed with the positioning microscopes 34 and 34', and the manual drive device 32
and 32' to move the wiring pattern or the alignment pattern of the printed wiring board 1 to be inspected placed on the stage 31 and the wiring pattern or the position of the printed wiring board 1' for comparison and verification placed on the stage 31'. Match the matching pattern. As a result, the patterns to be comparatively inspected on the printed wiring board 1 to be inspected and the printed wiring board 1' for comparison and verification can be aligned with each other.

Next, above the wiring surface 2 of the printed wiring board 1, there is a half mirror 23 that reflects the light from the light source 21 applied from the side and irradiates it onto the wiring surface 2, and allows the reflected light from the wiring surface to pass upward. , a lens 24 that collects the light passing upward from the mirror 23 and forms an optical image;
An image sensor 25 that converts the brightness of the image into a large number of electrical signals 26 is provided at the position where the optical image is formed, and the electrical signal 26 obtained from the left image sensor 25 and the right image sensor 2
A comparison/verification device 27 that recognizes the electrical signal 26' obtained from 5' as a wiring pattern and compares and verifies it.
is provided, and the comparison and verification device 27 indicates the presence or absence of a defective portion or points out the defective location. For example, when inspecting a printed wiring board 1 as shown in FIG. 4a, the light emitted from the light source 21 in FIG. , 42, 43, each portion of the wiring surface 2 of the printed wiring board 1 is irradiated. The light ray 41 produces a low level of reflected light 51 due to the low reflectivity of the insulating base material 7, the light ray 42 produces a high level of reflected light 52 due to the high reflectance of the wiring pattern 5 made of metal such as copper, and the light ray 43 produces a high level of reflected light 52 due to the high reflectivity of the wiring pattern 5 made of metal such as copper. No reflected light is generated to pass through the through hole 6, ie, the through hole, to the wiring surface 3 on the back side. The light rays 51 and 52 reflected upward in this way are reflected by the half mirror 2 in FIG.
3. The image is formed as an optical image on the image sensor 25 via the lens 24. The image sensor 25 is composed of a large number of microscopic light-receiving elements arranged in a straight line.
For example, there is one in which 256 elements are arranged in a length of 5 mm.

FIG. 4b is a plot of the electric signal 26 that appears when the reflected lights 51 and 52 of FIG. The signal level is taken, and the horizontal axis shows the element position of the image sensor. In the figure, _I1 indicates the electrical signal level at the through-hole position, and is at a low level because there is almost no reflected light from the wiring surface. I ₂ is the reflected light 51 from the insulating base material 7 converted into an electrical signal, and is higher than I ₁ but at a lower level. I ₃ is the reflected light 52 from the wiring pattern 5 converted into an electrical signal and has a high level. In order to facilitate comparison and verification of these various levels, it is necessary to convert them into two types, a bright level and a dark level, that is, into binary values. For this reason, as shown in FIG. 4b, when the electric signal level is converted to a bright level when it is higher than I _S and to a dark level when it is lower than that, for example, by a binarization circuit 28 consisting of a voltage comparator, The wiring pattern 5 is converted into a binary signal with a bright level (binary "1"), and the insulating base material 7 and the through hole 6 are converted into a binary signal with a dark level (binary "0"). Since the light-receiving surface of the image sensor 25 is linear, the binary signal obtained in this way becomes linear information (linear information as seen from the pattern in Figure 1 along line A-A'). ing. Therefore, by storing the binary signal in the memory 29 while moving in parallel along the printed wiring surface, surface information can be obtained in the memory 29.
Thereafter, the surface information stored in the memory 29 is compared and verified by the pattern comparison circuit 30, and portions that do not match are displayed as defects.

According to the above-described inspection apparatus, it is very important to mutually align the patterns to be comparatively inspected on the printed wiring board 1 to be inspected and the printed wiring board 1' for comparison and verification. In this alignment method, printed wiring board manufacturing methods generally form through holes based on guide holes,
Photo original plate (mask) based on the through hole
In order to form a wiring pattern by aligning the wiring patterns, the mutual positions of the wiring patterns with respect to the guide holes on the printed wiring board 1 to be inspected and the printed wiring board 1' for comparison and verification are not necessarily the same. This alignment method has a problem in that patterns to be compared and inspected cannot be accurately aligned with each other. In addition, for example, in a method in which the actual wiring pattern or a pattern specially prepared for alignment is aligned by moving a manual drive device while observing it with a positioning microscope, the patterns to be comparatively inspected can be accurately aligned with each other. I get it, but
There was a problem that alignment took a lot of time.

SUMMARY OF THE INVENTION An object of the present invention is to provide a wiring pattern positioning device that automatically and accurately aligns patterns to be comparatively inspected.

The gist of the present invention is to perform positioning by detecting the wiring pattern itself, rather than by using through holes. At this time, the wiring pattern may be the wiring pattern originally formed on the printed wiring board itself, or a wiring pattern specially formed for inspection (more precisely, it should be called an inspection pattern). You may.
Furthermore, optical means are used to detect the wiring pattern, and the incident light for detection is set at a specific angle. The present invention will be explained in detail below with reference to the drawings.

FIG. 5 is a diagram showing an embodiment of the present invention. Third
The same symbols as in the figure indicate the same content. The difference from FIG. 3 is that a control device 35 is provided which inputs the comparison results of the pattern comparison circuit 30, and the output 36 of the control device 35 is used to control the driving devices 39, 39'.
The driving devices 39, 39' drive the stages 31, 31' to perform position adjustment and positioning. The drive devices 39, 39' and the stages 31, 31' form a so-called positioning mechanism. Furthermore, it was decided to project the incident light onto the printed wiring boards 1, 1' from the lateral direction rather than directly above, and in order to realize this lateral projection, lamps 37,
37' and lenses 38, 38' are also different. The components shown in FIG. 3 that have been excluded are the positioning microscopes 34, 34', the light source 21,
21', half mirrors 23, 23', etc.

FIG. 6 shows the relationship between printed wiring board 1 (same as 1') and incident light. Printed wiring board 1 as shown in figure a.
Side wall surface 15 of wiring pattern 4 formed above
Incident light 44 is projected from the lateral direction. This incident light 44 is light emitted from the lamp 37 via the lens 38. Incident light 4 hitting the side wall surface 15
4 is reflected by the side wall surface 15, becomes reflected light 53, and forms an image on the image sensor 25 via the upper lens 24. Therefore, the output 26 of the image sensor 25 generates an output I on the vertical axis in which only the portion that receives the reflected light 53 is at a high level _I1 , as shown in Figure b. Other parts are at low level, such as _I2 . Therefore, by setting the threshold value I _S to an intermediate value, the portions that have received the reflected light 53 and the portions that have not received the reflected light 53 can be accurately distinguished, and the position of the side wall surface of the wiring pattern 4 can be detected.

The above operations are similarly performed on the printed wiring board 1'. The wiring patterns on which the side wall surfaces of both printed wiring boards 1 and 1' are to be detected are wiring patterns set for mutual positioning, or wiring patterns formed for mutual positioning. Therefore, the positional relationship with the printed wiring boards 1, 1' is also determined depending on the positional relationship of the reflected light images formed on the image sensors 25, 25' with respect to each other. The positions of the printed wiring boards 1 and 1' are adjusted by the control device 35 and the drive devices 39 and 39' so that the positions of the printed wiring boards 1 and 1' match so that the positions match.

Next, the relationship between the degree of inclination of the side wall surface 15 of the wiring pattern 4 and the incident angle of the incident light 44 will be explained using FIG. 7. The wiring pattern 4 has a wiring side surface 15 having an arbitrary slope, and is laminated on the printed wiring board 1. The wiring side surface 15 is a curved surface formed by side etching, and its cross section depicts a curved line with a curved portion on the conductor wiring side. Therefore, as shown by the arrow in the figure, light incident at a certain angle of incidence is reflected upward by the wiring side surface 15 according to the law of light reflection, and is reflected upward by the lens 24.
The image is captured by the image sensor 25 via the image sensor 25.

For example, when illumination light is irradiated at a certain incident angle θ and the wiring side surface 15 is inclined at an angle θ ₀ with respect to the water level, the illumination angle θ is as follows: θ≦2θ ₀ −90°+α ...(1) θ≧ 2θ ₀ −90°−α ...(2) is determined. However, α is the angle between the optical axis and the edge of the lens, and when illuminating at the incident angle shown in equations (1) and (2), the reflected light from the wiring side surface 15 is correctly captured on the image sensor 25. be able to. An example of angle determination based on the above process is shown in FIG. In the figure, the incident angle of the incident light 44 with respect to the wiring side surface 15 is set to 85 degrees. Further, the maximum angle between the optical axis of the lens 24 and the reflected light 53 is 15 degrees.

On the other hand, there are various types of wiring patterns. A solder pattern that has been widely used recently is a solder pattern formed by coating a copper pattern with solder. Unlike the general wiring pattern shown in FIGS. 7 and 8, the solder pattern has a shape in which solder is bulged on the upper surface of the copper pattern. Therefore, the incident angle setting of the light is also different from that in FIG. The angle of incidence in the solder pattern will be explained using FIG. 9. In FIG. 9, a printed wiring board 1 is provided with a copper pattern 4A, and a solder pattern 4B is formed on the surface of the copper pattern to form a solder pattern. Assuming that the solder pattern 4B laminated on the surface of the copper pattern 4A has an inclination, incident light incident from the direction shown in the figure is reflected at the boundary between the copper pattern 4A and the solder pattern 4B. This reflected light is at the limit of entering the lens 24, and the reflected light must not pass through the lens 24 in the portion where it enters the surface area of the solder pattern 4B from this boundary. The reason is that the edges of the solder pattern are detected.
This is because the pattern is detected by detecting this edge portion. Based on this condition, the angle θ of the incident light is calculated as θ<90°−(2+α) (3).

For example, if α=90° and =30°, then from equation (3), θ<10°. Therefore, when θ=5°, from equations (1) and (2), θ ₀ ≧37.5 and θ ₀ ≦57.5. That is, the inclination angle θ ₀ of the copper pattern 4A is 37.5
Detection is possible within the range of °≦θ ₀ ≦57.5°.

Next, the characteristics of the wiring pattern and the installation location will be described. The wiring patterns include wiring patterns that are actually used for wiring and wiring patterns that are not used. On the other hand, the printed wiring board must be positioned in a position where it can be easily positioned when viewed from two mutually intersecting axes X-Y. A position that is easy to position is based on the assumption that the wiring pattern to be inspected is parallel to the X-axis or the Y-axis. A printed wiring board has a rectangular or square shape, and its two perpendicular surfaces are generally set as the X and Y axes. Therefore, a wiring pattern that is parallel to the plane is easy to position. In addition, being located in the peripheral area of the printed wiring board,
This is convenient for projecting externally incident light.
A wiring pattern that satisfies the above requirements can be formed in a wiring pattern manufacturing process. The wiring patterns that can be inspected are of a character that will eventually be removed as unnecessary items.

In addition to the wiring pattern obtained through the above manufacturing process,
A special wiring pattern can also be formed for positioning. In this case, it should be called a positioning inspection pattern rather than a wiring pattern.

Next, based on the above premise, the actual positioning operation will be explained. FIG. 10 shows alignment inspection patterns 63, 6 on printed wiring boards 1, 1'.
3', 63b, and 63b' are shown. The patterns 63 and 63' are parallel to the X axis, and the patterns 63b and 63b' are parallel to the Y axis. Further, in order to detect the wiring patterns 63, 63' at positions close to both ends of the patterns 63, 63', lamps 37, 37a, 37', 37'a, lenses 38, 38a, 38', 38'a, and image sensors are installed. 25, 25a, 25', and 25'a (however, the lens corresponding to the lens 24 is omitted in the drawing). Furthermore, patterns 63b, 6
3'b, lamps 37b, 37'b, lenses 38b, 38'b, image sensors 63b, 6
3'b is provided. Furthermore, patterns 61 and 62
is the wiring pattern that is actually compared and verified after positioning.

Based on the above configuration, the image sensors 25, 2
5'25a, 25'a and output signal 2
11a and 11b show the positional relationship in which 26a and 26'a occur. I _S indicates a threshold, I ₂ indicates a low level, and I ₃ indicates a high level. The positional relationship between the image sensors 25, 25', 25a, and 25'a is used to calculate the amount of positional deviation between the wiring boards 1 and 1'. Let me explain this clearly.

Each image sensor is a line sensor and has a photoelectric detection area in the longitudinal direction. When the photoelectric detection area in the longitudinal direction is divided into small unit areas, each unit is a ₁ , a ₂ , ..., a′ ₁ , a′ ₂ ,
It can be expressed as... When reflected light from the edge of the wiring pattern enters this longitudinal photoelectric detection area, the photoelectric detection area corresponding to the incident position generates a large current due to photoelectric action, and other photoelectric detection areas without reflected light Almost no photoelectric effect occurs, and the current is weak. That is, according to the line sensor, it can be determined from which position the reflected light is large. The detection signals from the line sensors may be taken out in parallel or in series, and the methods for taking them out are self-evident.

In any case, each image sensor 25, 2
5', 25a, 25'a, 25b, 25'b, etc.
A large detection current is obtained at a position corresponding to the position of the wiring pattern of interest that is irradiated with light. The output of this image sensor is the binarization circuit 2
It is binarized at 8,28'. In the binarized electrical signal, the light irradiation position can be identified based on its magnitude (the portion that becomes "1") and the position of occurrence. Therefore, the existence and amount of positional deviation between the wiring boards 1 and 1' can be determined from the magnitude and generation position of each detection signal (actually, a binary signal) of each image sensor. The position of the wiring board is adjusted and positioned according to the amount of positional deviation.

Now, in FIG. 11, a ₁ , a' ₁ . . . are unit detection areas, which will be referred to as light-receiving element numbers of the image sensor. Figure a shows how the detection element positions in sensors 25 and 25' are different, and figure b shows 2
It shows how the detection element positions at 5a and 25'a are different. Therefore, patterns 63, 63'
It can be seen that both are tilted, that is, that the printed wiring boards 1 and 1' are tilted relative to the X-axis, and that they are also moving in the Y-axis direction from both figures a and b. In addition to figures a and b, pattern 6
3b and 63'b as well, pattern detection is performed by the sensors 25b and 25'b in the same way as in figures a and b.

The above image sensors 25, 25a, 25',
The outputs of 25'a, 25b, and 25'b are binarized by a binarization circuit, temporarily stored in a memory, and compared by a comparison circuit. The control device 35 receives this comparison result and calculates what displacement should be applied to the drive devices 39, 39' in order to match the positions. This comparison circuit and displacement calculation mechanism constitute a so-called displacement calculation section. According to the calculation result, the driving devices 39, 39' move the driving stage 31,
Move 31' and measure the match.

Below, we will describe the above calculation in more detail, including the contents of the calculation.

In the printed wiring board 1 arbitrarily placed on the stage as shown in FIG.
The xy coordinate axes on 1 correspond to the moving direction of the stage or the moving direction of the image sensor.
The x′y′ coordinate axes that do not generally coincide with the coordinate axes and exist on the comparison matching pattern 62 are also XY
Not aligned with the coordinate axes. Therefore, as shown in FIGS. 11a and 11b, the position of the alignment pattern appearing on the image sensor is a _q for the image sensor 25, a' for the image sensor 25', a p for the image sensor 25a, and a _p for the image sensor 25a'.
This is recognized as a bright level (binary "1") in the light receiving element located at each position of _a'j . Therefore, in order to match the rotation angle of the xy coordinate axes existing in the pattern to be inspected 61 with the rotation angle of the XY coordinate axes in the moving direction of the stage or the moving direction of the image sensor, it is necessary to The length in the direction, that is, the width of each light receiving element is l, and the distance between the image sensor 25 and the image sensor 25a is L, the pattern to be inspected 6.
It turns out that it is sufficient to rotate 1 clockwise by an angle of tan ^-1 [(q-p)·l/L]. If the control device 35 in FIG. 5 controls the drive device 39 by sending a clockwise rotation command with a drive amount corresponding to the rotation angle, the rotation angle of the xy coordinate axes existing in the pattern to be inspected 61 can be controlled by moving the stage. It is possible to match the direction or the rotational direction of the XY coordinate axes, which corresponds to the moving direction of the image sensor.

The positional relationship of detection signals from the sensor obtained by the above operations is shown in FIGS. 12a and 12b. The bright level light receiving element position indicating the alignment pattern position of the image sensor 25 in Figure A and the image sensor 25a in Figure B is the same and is indicated by a _n . Similarly, the image sensor 25' in figure a
The bright level light receiving element position indicating the alignment pattern position of the image sensor 25a' in _FIG .

Next, to align patterns 61 and 62 in the Y direction, compare pattern 62 (r-
It is sufficient to move by m)·l in the negative direction of Y. FIGS. 13a and 13b show a state in which alignment in the rotational direction and the Y direction has been completed. The bright level light receiving element positions are image sensors 25, 25', 25a, 25'a.
Both are a _n or a′ _n .

To align the patterns 61 and 62 in the X direction, image sensors 25b and 25'b, condensing lenses 38b and 38'b, and light sources 37b and 37'b are provided. Under this configuration, the image sensor 25b receives the reflected light from the pattern 63b, the image sensor 25'b receives the reflected light from the pattern 63'b, and the positions of the respective light receiving elements are determined. Perform alignment from The details of this alignment method will be omitted since alignment can be performed in exactly the same way as in the Y direction.

FIGS. 14a and 14b are diagrams showing another embodiment of the present invention, in which figure a is a side view and figure b is a plan view. In FIG. 14, 64 is a plated lead wire of a plug terminal, and other parts with the same reference numerals indicate the same parts as in the previous embodiment. Since there are two or more patterns of the same type on the printed wiring board 1 and the connection terminals must be fully plated or rhodium plated, plated lead wires are generally present. The present embodiment was made with attention to this point, and the difference between this embodiment and the previous embodiment is that the x and y coordinate axes in the pattern coincide with each other in the printed wiring board 1 as shown in FIG. Inspected pattern and comparison pattern 6
2, the relative position with respect to the pattern to be inspected 61 and the pattern for comparison and verification 62 is the same, and the mated lead wire 64 of the plug terminal is parallel to the x-coordinate axis of the x-y coordinate axes and can be used as an alignment pattern. The point is that there is. In addition, this embodiment controls two light sources 37, 37', two condensing lenses 38, 38', two image sensors 25, 25', a drive unit 39 that drives the stage 31, and a drive unit 39. The control device 35 further includes an electric signal comparison and verification device 27.

The electrical signal comparison and verification device 27 includes two binarization circuits 28 and 28', two memories 29 and 29', and a pattern comparison circuit 30. Binarization circuit 28, 2
8' receives the detection signals 26, 26' from the image sensors 25, 25', respectively, and obtains a binarized signal by comparing the levels I ₂ and I ₃ with a predetermined threshold I _s . That is, level I ₂ is "0" and level I ₃ is "1". The generation positions at which the binarized signals are generated are taken in as data into the memories 29 and 29', respectively, and temporarily stored therein. Pattern comparison circuit 30
reads mutually corresponding data stored in the memories 29 and 29', and if there is a difference in position,
Find the difference. Then, a control command (rotation command) is sent to the control device 35 so that the difference becomes zero, and the drive unit 39 is rotationally driven for alignment.

Next, the mutual alignment operation of comparative test patterns will be explained using FIG. 15. As shown in FIG. 15a, in the printed wiring board 1 arbitrarily installed on the stage, the are not consistent. As a result, the position of the lead wire of the plug terminal that appears on the image sensor is determined by the brightness level of the light-receiving element present at each position _ak for the image sensor 25 and a′ _j for the image sensor 25', as shown in FIG. 15b. (binary “1”). Therefore, in order to match the xy coordinate axes existing in the comparative inspection pattern with the The width of one light receiving element is l', the distance between the image sensors 25 and 25' is L', and the printed wiring board 1 is tan ^-1.
It can be seen that it is sufficient to rotate clockwise by an angle of [(k-j)·l'/L']. If the control device 35 controls the drive device 39 by sending a clockwise rotation command with a drive amount corresponding to the rotation angle, the xy coordinate axes existing in the comparison inspection pattern and the XY coordinate axes corresponding to the moving direction of the stage or the moving direction of the image sensor are controlled. can be matched. FIG. 16a shows the electrical signal 26 appearing on the image sensor when alignment is completed. The bright level light receiving element position indicating the position of the plated lead wire of the plug terminal is a _n or a' _n for both image sensors 25 and 25'.
Unlike the first embodiment, in this embodiment, when alignment in the rotational direction is performed, the alignment in the Y direction is also automatically performed. X
As for the direction, since the distance between the patterns 61 and 62 is determined as a design value, it is sufficient to set the distance between the image sensors 25 and 25' for comparison and verification to the design value, which greatly simplifies alignment.

As described above, the present invention has the following effects.

(1) By irradiating the wiring surface with light whose incidence angle is close to 90 degrees, the image sensor can capture the reflected light from the side of the wiring pattern.

(2) By controlling the drive device based on the information obtained from the reflected light from the side surface of the wiring pattern, the comparative inspection patterns can be aligned with each other.

(3) The blind lead wire of the plug terminal can be used for mutual alignment of comparative inspection patterns.

Since the printed wiring pattern can be automatically aligned in this way, the wiring pattern can be quickly automated and inspected, saving labor and improving the reliability of the printed wiring board.

[Brief explanation of the drawing]

Fig. 1 is an example of a wiring pattern, Fig. 2 is a configuration diagram of a wiring board, Fig. 3 is a conventional configuration diagram, Figs. Figures 6a and b are explanatory diagrams, Figures 7, 8 and 9 are other explanatory diagrams, Figure 10 is a diagram showing the actual system, Figures 11a and b, Figure 12a, b, Figure 13 a, b
is an explanatory diagram of the image sensor that detected the pattern,
Figures 14a and 14b are diagrams of other embodiments; Figures 15a and 15b are diagrams of other embodiments;
b, and FIGS. 16a and 16b are explanatory diagrams thereof. 1, 1'...Printed wiring board, 2, 2'...Wiring surface,
4... Wiring pattern, 27... Comparison verification device, 3
5...Control device.

Claims (1)

[Claims] 1: first and second positioning mechanisms; a first wiring board disposed on the first positioning mechanism; and a second wiring board disposed on the second positioning mechanism. , a first projector that projects light from the lateral direction onto a part of the wiring pattern on the first wiring board; and a first projector that forms an image of reflected light obtained by the projection.
a second projector that projects light from a lateral direction onto a part of the second wiring pattern corresponding to the part of the first wiring pattern; second image forming
a calculation unit that calculates a mutual positional deviation between the first and second wiring boards by comparing the magnitudes and the positions of the detection signals of the first and second sensors; A wiring pattern positioning device comprising: a control device that controls the first and second positioning mechanisms based on the above-mentioned information to correct positional deviations of the first and second wiring boards; 2. Parts of the first and second wiring patterns are:
2. The wiring pattern positioning device according to claim 1, wherein the solder pattern is a solder pattern, and the light incident from the lateral direction is incident from the edge direction of the solder pattern. 3. A positioning mechanism, a wiring board disposed on the positioning mechanism, and corresponding parts of the first and second wiring patterns on the wiring board to be compared with each other,
First and second projectors that respectively project light from the lateral direction, and first and second sensors that form images of the first and second reflected lights from mutually corresponding positions obtained by the projection. a calculation unit that calculates the positional deviation of the wiring board by comparing the magnitudes and the positions of the detection signals of the first and second sensors, and controlling the positioning mechanism based on the calculation result to A wiring pattern positioning device consisting of a control device that corrects misalignment of a wiring board, and a wiring pattern positioning device. 4. Parts of the first and second wiring patterns are:
4. The wiring pattern positioning device according to claim 3, wherein the wiring pattern is a solder pattern, and the light incident from the lateral direction is incident from the edge direction of the solder pattern.