JPH0658736A - Method and device for three dimensional shape inspection - Google Patents

Abstract

PURPOSE:To judge good or bad of cream solder print from the estimation of the three dimensional shape by extracting the distribution position of each particular color corresponding to particular shapes such as inclined part, concave part, covex part and the like from the color image data of an inspected body. CONSTITUTION:From a color image 1 of a printed base plate of an inspected body cream solder printed, an image cut out memory cuts out an inspection object image 2 and stores it. The solder cross section 19 has a three dimensional shape. The color distributions 3 of whole solder, of circumferential inclined plane 20, of flat part 21, of concave part 22 are stored in a particular color distribution memory means. Each particular color of these color distributions 3, 20, 21, 22 is extracted from the color image 1, the image position is extracted, plane views 23, 24, 25, 26 are combined and a plane view 27 is obtained. By combining this plane view 27, three dimensional shape of the inclined plane 29, three dimensional shape of the flat part 30 and three dimensional shape of the concave part 31, a cross sectional view 32 combining each particular shape part is obtained and the three dimensional shape is estimated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image inspection method and apparatus using color image data, and in particular, it determines whether or not cream solder printing is good or bad on a printed circuit board for an electronic circuit in a production process of electronic equipment. Printing 3
The present invention relates to a three-dimensional shape inspection method and a three-dimensional shape inspection device that estimate and determine a three-dimensional shape.

[0002]

2. Description of the Related Art A conventional cream solder printing inspection method is shown in FIG.
It will be described based on the conceptual diagram shown in FIG.

In FIG. 5, in the conventional example, first, a color image at the inspection target screen position 2 is cut out from the color image 1 of the electronic circuit printed circuit board of the inspection target printed with cream solder.

The color image at the inspection target screen position 2 includes a color image 7 for cream solder printing. Reference numeral 3 denotes color distribution data of colors included in the color image 7 for cream solder printing. When the screen position where the color distribution data 3 of the color image 7 of the cream solder printing exists is extracted from the color image of the inspection target screen position 2, the cream solder printing screen position data 4 indicating the two-dimensional shape and position of the cream solder printing is obtained. can get. Image processing 5 is performed based on the cream solder printing screen position data 4, and the quality 6 of the solder paste printing is inspected 6.

[0005]

However, since the image processing of the two-dimensional shape is performed in the above-described configuration of the conventional example, it is assumed that the height of the solder in the cream solder printing portion is always constant. The quality is judged based on the shape, dimensions, and area of the plan view of the printing section.

Therefore, the height of the solder in the cream solder printing portion changes due to the change in the printing condition of the cream solder,
Even if the amount of printed solder changes, if the area of the plan view of the cream solder printing portion is within the specified value range, the inspection result is determined to be good. Therefore, in reality, even if the height of the solder in the cream solder printing part has changed and the printed solder amount is excessive or insufficient, the inspection result is judged to be good if the area is within the specified value range. There is a problem that

In order to solve the above problems, the present invention provides a three-dimensional shape inspection method and a three-dimensional shape inspection apparatus for determining and inspecting the three-dimensional shape of solder in a cream solder printing section. It is an issue.

[0008]

The three-dimensional shape inspection method of the present invention, in order to solve the above-mentioned problems, inspects the three-dimensional shape of the inspection object from the color image data of the inspection object, From the color image data of the inspection object, the positions of the specific color distribution screens in which the specific color distributions corresponding to the specific shape portions such as the inclined surface, the concave portion, the convex portion, and the flat surface portion of the three-dimensional shape portion of the inspection object are present. The shape, dimensions, and area of each specific color distribution screen position are measured and extracted, and the inclined surface of the specific shape portion, the concave portion,
The shape of the convex portion, the flat surface portion, or the like is applied to the shape, the dimension, or the area to estimate the three-dimensional shape, dimension, or volume of the three-dimensional shape portion of the inspection object, or the inclined surface, the concave portion, the convex portion, It is characterized in that the quality of the three-dimensional shape is judged by calculating the ratio of the dimensions, area, etc. of the plan view between the specific shape portions such as the flat portion and estimating the shape, dimensions and volume of the three-dimensional shape portion.

In order to solve the above problems, the three-dimensional shape inspection apparatus of the present invention includes a camera for picking up a color image of an inspection object, and an inclined surface, a concave portion, and a convex portion of the three-dimensional shape portion of the inspection object. , A specific color distribution storage unit that stores a specific color distribution corresponding to a specific shape portion such as a flat surface portion, and a specific color distribution screen in which the specific color distribution exists for each specific color distribution corresponding to each specific shape portion A specific color distribution screen position extracting means for measuring / extracting the position to determine the shape / dimension / area of each specific color distribution screen position, and the shape of the specific shape portion such as the inclined surface, the concave portion, the convex portion, and the flat surface portion. Estimating the three-dimensional shape, size, and volume of the three-dimensional shape part of the inspection object by applying it to the shape, size, and area, or the plane between the specific shape parts such as the inclined surface, the concave portion, the convex portion, and the flat surface portion. Calculate the ratio of dimensions, area, etc. on the figure to calculate the shape and dimensions of the three-dimensional shape And having a three-dimensional shape determination means for determining the quality of estimation to the three-dimensional shape of the volume.

[0010]

According to the three-dimensional shape inspection method of the present invention, in order to inspect the three-dimensional shape of the inspection object from the color image data of the inspection object, the three-dimensional shape portion has an inclined surface, a concave portion, a convex portion,
The fact that the color distribution of the color image data is different for each specific shape such as a plane portion is used.

Therefore, the specific color distributions peculiar to the specific shape parts such as the inclined surface, the concave part, the convex part and the flat part of the three-dimensional shape part of the inspection object are measured in advance, and first, the specific color Each specific color distribution screen position having a distribution is measured and extracted to obtain the shape, size, and area of each specific color distribution screen position.

The shape, size, and area of these specific color distribution screen positions are determined by the sloped surface, the concave portion, and the three-dimensional shape of the inspection object.
Since it is a plan view corresponding to a specific shape portion such as a convex portion and a flat portion, the specific color distribution screen position indicating the color distribution of the inclined surface is the inclined surface, and the specific color distribution screen position indicating the color distribution of the concave portion is the concave portion. , The specific color distribution screen position showing the color distribution of the convex part is the convex part, the specific color distribution screen position showing the color distribution of the flat part is the flat part, and the shapes of the inclined surface, the concave part, the convex part, and the flat part are applied respectively. Then, the pass / fail can be determined by estimating the three-dimensional shape / dimension / volume of the inspection target.

Further, when the ratios of dimensions, areas, etc. on the plan view between the specific shaped portions such as the inclined surface, the concave portion, the convex portion and the flat surface portion are calculated, each specific shaped portion is inspected by the calculation result. The pass / fail can be determined based on the proportion of the object in the three-dimensional shape portion (the volume of the three-dimensional shape portion can be estimated).

That is, as in the conventional example, for example, a three-dimensional inspection object such as a cream solder printing portion is not two-dimensionally determined by comparing the area of its plan view with a reference value. According to the present invention, it is possible to judge pass / fail by estimating the three-dimensional shape, size, and volume of a three-dimensional inspection object such as a cream solder printing unit, so that the reliability of the inspection is improved. With respect to the work of (3), it is possible to add the data of the amount of solder to the defect content data and feed it back as easy-to-determine data, so that an accurate response can be implemented in a short time.

In the three-dimensional shape inspection apparatus of the present invention, a camera for picking up a color image of the inspection object and a specific shape portion such as an inclined surface, a concave portion, a convex portion or a flat surface portion of the three-dimensional shape portion of the inspection object are provided. Specific color distribution storage means for storing the corresponding specific color distribution,
A specific color distribution for each specific color distribution corresponding to each of the specific shape parts. A specific color distribution screen position in which the specific color distribution exists is measured / extracted to obtain the shape / dimension / area of each specific color distribution screen position. The screen position extracting means and the three-dimensional shape / dimension of the three-dimensional shape portion of the inspection object by applying the shapes of the inclined surface, the concave portion, the convex portion, the flat surface portion, etc. of the specific shape portion to the shape / dimension / area. Estimate the volume, or the inclined surface, the recess,
A three-dimensional shape that determines the quality of the three-dimensional shape by calculating the ratio of the dimensions, areas, etc. on the plan view between the specific shapes such as the convex portion and the flat portion, and estimating the shape, dimensions, and volume of the three-dimensional shapes. The above-described three-dimensional shape inspection method of the present invention is implemented by using a determining unit.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a three-dimensional shape inspection method according to the present invention. An embodiment of a three-dimensional shape inspection apparatus using the method will be described with reference to FIGS. To do.

In FIG. 1, in the present embodiment, a camera 8 having a lighting device for illuminating an inspection object and color-imaging the inspection object, and color image data 9 color-imaged by the camera 8 are shown.
A color image memory 10 for storing a color image data, a color image data stored in the color image memory 10, and an inspection target screen cutout memory 11 for cutting out and storing an inspection target screen; and a specific color distribution storage unit 12 for storing a specific color distribution. , A control unit 1 having a CPU, an inspection program, a memory for storing inspection information of various inspection items, and the like, and controlling the entire three-dimensional shape inspection apparatus
8, a specific color distribution table designation data memory 17 that stores specific color distribution table designation data that designates a specific color distribution table to be used, and a specific color distribution table designation data memory 17 under the control of the control unit 18. Specific color distribution screen position extraction for calling the specified specific color distribution table from the specific color distribution storage means 12 based on the specified color distribution table specification data and extracting the screen position of the specific color distribution from the inspection target screen based on this. A means 13, a specific color distribution screen position memory 14 for storing the extracted specific color distribution screen position, and a shape / dimension of the specific color distribution screen position.
It has a three-dimensional shape determining means 15 for determining a three-dimensional shape by an operation that combines areas and an output unit 16.

Next, the operation of this embodiment will be described with reference to FIGS.

1 to 4, the color image 1 of the printed circuit board for electronic circuit of the inspection object printed by cream solder which is picked up by the camera 8 and stored in the color image memory 10 is printed.
Then, the inspection target screen cutout memory 11 cuts out and stores the inspection target screen 2. 7 is a cream solder to be inspected and has a three-dimensional shape with a cross section 19 The specific color distribution storage unit 12 stores a specific color distribution corresponding to each specific shape portion of the three-dimensional shape 19. In FIG.
(A) The left side of the plan view shows the two-dimensional shape of the cream solder on the plan view, and (b) the right side of the three-dimensional shape shows the three-dimensional shape of the cream solder estimated from (a). In the present embodiment, the color distribution 3 of the whole cream solder of FIG. 2A, the color distribution 20 of the inclined surface of the cream solder, the color distribution 21 of the flat portion of the cream solder, and the color distribution of the depressed portion of the cream solder. 22 is stored in the specific color distribution storage means 12.
If the color unique to each of these color distributions 3, 20, 21, and 22 is extracted from the color image 1 and the screen position where the color exists is extracted, the screen position will be the whole of the cream solder of (a). Plan views 23 and 28 of FIG.
Plan views 25 and 30 of the flat portion, and plan views 26 and 3 of the depressed portion
Becomes 1.

Plan view 24 of the inclined surface, plan view 2 of the flat portion
5. By combining the plan views 26 of the recessed portions, as shown in the combined plan view 27, the two-dimensional shape, size, and area in the plan view of each specific shape portion can be obtained.

For the inspection of the three-dimensional shape, the combined plan view 27 is combined with the three-dimensional shape 29 of the inclined surface, the three-dimensional shape 30 of the flat portion, and the three-dimensional shape 31 of the recessed portion to combine each specific shape portion. The cross-sectional view 32 is obtained and the three-dimensional shape is estimated.

The actual shape of the cream solder includes the solder plan view and the solder sectional views 33 to 37 shown in FIG. 33 is a solder shape without an inclined surface, 34 is a solder shape with an inclined surface, 35 is a conical solder shape, 36 is a dented solder shape, and 37 is a distorted solder shape.

The inspection of the three-dimensional shape is performed by combining the two-dimensional dimensions and areas obtained from the combined plan view 27 to calculate and estimate the three-dimensional shape.

An example of this calculation is shown in FIG. In FIG. 4, when the area of the plan view 27 is used, the ratio of the area of each specific shape portion to the entire area of the solder, (inclined portion area) / (total area) = S ₂ / S ₁ (recessed portion area ) / (Overall area) = S ₃ / S ₁ (flat area) / (Overall area) = S ₄ / S ₁ etc., the three-dimensional shape of the cross-sectional view 32 can be estimated. In this case, it is sufficient to determine whether the quality is good as long as S ₂ and S ₃ are small. Therefore, it is determined that S ₂ / S ₁ and S ₃ / S ₁ are equal to or less than a predetermined value.

In FIG. 4, when the dimensions of the plan view 27 are used, the ratio of the dimensions of each specific shape portion to the overall dimensions of the solder, (inclined portion dimension) / (overall dimension) = 2a / L (recessed portion Dimension) / (overall dimension) = b / L (flat portion dimension) / (overall dimension) = (L-2a-b) / L etc., the three-dimensional shape of the sectional view 32 can be estimated. . In this case, it is sufficient to judge whether the quality is good or not, so that a and L are small, and therefore 2a / L and b / L are judged to be good when they are equal to or less than a predetermined value.

The above determination is performed by the three-dimensional shape determining means 15 of FIGS. 1 and 2, and the determination result is output by the output unit 16 of FIGS.

The output of the output unit 16 is fed back to the host computer, the cream solder printing apparatus, etc. as an inspection result. This feedback data can be supplied not only for quality judgment but also for data such as area ratio, dimensional ratio, volume ratio, positional deviation of each specific shape portion including the passage of time,
Even if a defect occurs, the cause and countermeasure can be easily determined, so that it can be quickly improved.

The three-dimensional shape inspection method and the three-dimensional shape inspection apparatus of the present invention are not limited to the above-mentioned embodiments, but various modes are possible. For example, the configuration of the circuit in FIG. 1 and the sharing of operations can be freely designed.

Color image data captured in color by a camera is converted into RGB color space coordinates in a predetermined color space, for example, illuminance,
You may convert and use it for the color space coordinate of chroma and a pigment system.

If the specific shape portion of the three-dimensional shape of the inspection object is related to the color distribution, it can be used not only for solder but also for other inspection objects.

[0031]

According to the three-dimensional shape inspection method and the three-dimensional shape inspection apparatus of the present invention, the three-dimensional shape is utilized by utilizing the relationship between the specific shape portion of the inspection object having the three-dimensional shape and the color distribution of the portion. Measuring and extracting the two-dimensional color distribution of the inspection object, combining this color distribution with a specific shape to estimate the three-dimensional shape of the inspection object, or determining the two-dimensional size ratio and area ratio of the specific shape part. The inspection determination is performed by calculating and estimating the three-dimensional shape of the inspection object. Therefore, for example, when an inspection of cream solder printing is performed, the inspection determination is performed by estimating the three-dimensional shape of the inspection target instead of the determination of the conventional example in which the area of the plan view of the printed solder is compared with the reference value. Since the quality of the printed solder can be judged properly by judging the amount of the printed solder, the data such as the area ratio, the size ratio, the volume ratio and the positional deviation of the printed solder can be fed back including the passage of time. Even if a problem occurs, it is easy to determine the cause and countermeasure, and it is possible to improve quickly.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.

FIG. 2 is a conceptual diagram of the operation of the present invention.

FIG. 3 is a plan view and a sectional view of cream solder printing.

4 is an operation diagram of the shape determination of FIG.

FIG. 5 is a conceptual diagram of an operation of a conventional example.

[Explanation of symbols]

 8 camera 10 color image memory 11 inspection target screen cutout memory 12 specific color distribution storage means 13 specific color distribution screen position extraction means 14 specific color distribution screen position memory 15 three-dimensional shape determination means 16 output section 17 specific color distribution table designation data Memory 18 control unit

Claims (2)

[Claims] 1. In order to inspect the three-dimensional shape of the inspection object from the color image data of the inspection object, an inclined surface, a concave portion of a three-dimensional shape portion of the inspection object from the color image data of the inspection object, The shape, size, and area of each specific color distribution screen position are obtained by measuring and extracting each specific color distribution screen position where each specific color distribution corresponding to the specific shape part such as the convex portion and the flat surface portion exists.
Estimating the three-dimensional shape, size, and volume of the three-dimensional shape portion of the inspection object by applying the shapes of the inclined surface, the concave portion, the convex portion, the flat surface portion, etc. of the specific shape portion to the shape, dimension, and area, or , The quality of the three-dimensional shape is calculated by calculating the ratio of the dimension, area, etc. of the plan view between the specific shaped portions such as the inclined surface, the concave portion, the convex portion, and the flat portion to estimate the shape, dimension, and volume of the three-dimensional shaped portion. A three-dimensional shape inspection method, which comprises: 2. A camera for picking up a color image of an inspection object, an inclined surface, a concave portion, a convex portion of a three-dimensional shape portion of the inspection object,
Specific color distribution storage means for storing a specific color distribution corresponding to a specific shape portion such as a flat portion, and a specific color distribution screen position where the specific color distribution exists for each specific color distribution corresponding to each specific shape portion Specific color distribution screen position extraction means for measuring / extracting to obtain the shape / dimension / area of each specific color distribution screen position, and the shape such as the inclined surface, the concave portion, the convex portion, the flat surface portion of the specific shape portion -Estimating the three-dimensional shape, size and volume of the three-dimensional shape part of the inspection object by applying it to the size and area,
Alternatively, a three-dimensional shape is obtained by calculating the ratio of the dimension, area, etc. on the plan view between the specific shaped portions such as the inclined surface, the concave portion, the convex portion, and the flat portion to estimate the shape, dimension, and volume of the three-dimensional shaped portion. A three-dimensional shape inspecting apparatus, comprising: