JP2003240524A - Optical substrate visual inspection apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical substrate visual inspection apparatus by which a flat part and a grade part on a three-dimensional molded MID substrate are visually inspected simultaneously. <P>SOLUTION: The optical substrate visual inspection apparatus is provided with a first light irradiation means 2 by which a substrate 10 is irradiated with parallel light from a direction at right angles to the substrate; a second light irradiation means 3 by which the substrate 10 is irradiated with light from an oblique direction; at least a pair of third light irradiation means 4 in which optical filters used to transmit light in a wavelength band at a low spectral reflectance in the surface of the substrate 10 are interposed, and which are arranged and installed nearly symmetrically with reference to a virtual line parallel to a conveyance direction of the substrate 10 so as to cross an optical axis of the means 2 in order to irradiate the parallel light from the oblique direction at the substrate 10; and a CCD camera imaging means 5 which detects reflected light and scattered light reflected to the direction at right angles to the substrate 10 when beams of light from the first, second and third light irradiation means 2, 3, and 4 are irradiated. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical board appearance inspection apparatus for inspecting the appearance of a conductor pattern of a board or a bonding pad plated with gold, and more particularly to a three-dimensionally molded MID (Molded Inter).
connect device (three-dimensional injection molding circuit component) belongs to the technical field of an optical substrate visual inspection device suitable for visual inspection of a substrate.

[0002]

2. Description of the Related Art Various substrates used in electric products and electronic equipment are inspected for surface defects by an optical substrate appearance inspection device, and substrates which have passed the inspection and have no surface defects are shipped as products. . Examples of such an optical substrate appearance inspection device include, for example, JP-A-5-280952 (conventional example 1; optical printed circuit board inspection device) and JP-A-7-58500 (conventional example 2: appearance inspection). The device disclosed in (Device) is known.

The optical printed circuit board inspecting apparatus according to the conventional example 1 has a vertical illumination for irradiating a printed circuit board to be inspected with light in a vertical direction and an oblique illumination for irradiating light in an oblique direction with respect to a surface to be inspected. It is provided with a side illumination and inspects defects on the surface to be inspected of the printed circuit board by imaging combined light from both light sources with an imaging means such as a CCD camera. Further, the appearance inspection apparatus according to Conventional Example 2 inspects a substrate on which surface mount components are mounted, and the difference in spectral reflectance between different materials of the electrode portion (silver color) and the electrode portion (copper foil) of the substrate. Paying attention to, the configuration is such that the illumination wavelength is selected and illumination is performed.

[0004]

The optical printed circuit board inspecting apparatus according to the conventional example 1 or the appearance inspecting apparatus according to the conventional example 2 can inspect the board for defects. Considered useful. However, in the case of the optical printed circuit board inspecting apparatus according to the above-mentioned conventional example 1, if the irradiation direction of light is set only for an inspected object having a step like the MID board, the inspected object is inspected. It is not possible to inspect defects in the flat portion and the slope portion at the same time. In other words, since the defects of the flat portion and the sloped portion of the inspection target must be individually inspected, it takes a long time to visually inspect the inspection target having the flat portion and the sloped portion. However, there is a problem to be solved that the efficiency of visual inspection work cannot be expected.

Further, in the case of the appearance inspection apparatus according to the conventional example 2, the difference in the spectral reflectance between different materials of the electrode portion (silver color) and the electrode portion (copper foil) of the substrate is utilized to make the substrate Since the configuration is such that the appearance is inspected, it is not possible to perform a high-precision inspection because it is insufficient for the appearance inspection of an object to be inspected that has the same material as the MID substrate and has a different surface shape. There are issues to be solved.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an optical substrate visual inspection apparatus which enables simultaneous visual inspection of the flat portion and the inclined portion of a three-dimensionally molded MID substrate.

[0007]

The present invention has been made in view of the above circumstances, and therefore, in order to solve the above problems, the optical substrate visual inspection apparatus according to claim 1 of the present invention is adopted. The means irradiates a substrate having a flat portion and a slope portion on the surface with light, and detects the reflected light from the substrate to detect defects on the plated surface of the substrate, in the optical substrate visual inspection device, The first light irradiating means for irradiating parallel light from a direction orthogonal to the first light irradiating means, the second light irradiating means for irradiating the substrate with light obliquely, and the spectral reflectance on the surface of the substrate portion of the substrate are An optical filter that transmits light in a low wavelength band is interposed, and the reflected light from the gradient part of the substrate is not parallel to the parallel light emitted from the first light irradiating means with respect to the substrate. To irradiate the substrate From at least a pair of third light irradiating means and the first to third light irradiating means, which are arranged substantially in parallel with a virtual line intersecting the optical axis of the first light irradiating means in parallel with the transport direction. Image pickup means for detecting reflected light and scattered light reflected in a direction orthogonal to the substrate by the irradiation of the light.

According to a second aspect of the present invention, the means adopted by the optical appearance inspection apparatus is the optical substrate inspection apparatus according to the first aspect, wherein the optical filter is 400 nm to 50 nm.
It is characterized in that it is a blue filter that transmits light with a wavelength of 0 nm.

The means adopted by the optical appearance inspection apparatus according to claim 3 of the present invention is to irradiate a substrate having a flat portion and a slope portion on its surface with light, and detect the reflected light from the substrate. In the optical substrate visual inspection apparatus for detecting defects on the plating surface, first light irradiating means for irradiating the substrate with parallel light from a direction orthogonal to the substrate, and first light irradiating means for irradiating the substrate with light in an oblique direction. In order to irradiate the two-light irradiation means and the parallel light from an oblique direction in which the reflected light from the gradient part of the substrate is not parallel to the parallel light emitted from the first light irradiation means, the substrate At least a pair of third light irradiating means, which are arranged substantially in parallel with the imaginary line intersecting the optical axis of the first light irradiating means in parallel with the transport direction of the first light irradiating means. From the substrate by irradiation with light from The reflected light and the diffusely reflected light reflected in the direction orthogonal to the substrate are separated into red, green, and blue, and the defect in the flat portion is detected from the red or / and blue image, and the defect in the gradient portion is detected from the green image. It is characterized by comprising an image pickup means for detecting.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION An optical substrate visual inspection apparatus according to a first embodiment of the present invention will be described below with reference to FIG. 1 (a), which is a schematic side view, and A--A in FIG. 1 (a). Figure 1 of the line cross section
2B of FIG. 2B, which is an explanatory view of light scattering components of the irradiation light emitted from the second light irradiation unit and the irradiation light emitted from the third light irradiation unit toward the CCD camera, and a defect of gold plating. The description will be made with reference to FIG. 2B which is a plan view of the substrate showing the state in order.

Reference numeral 1 shown in FIG. 1 (a) indicates MI during conveyance.
This is an optical substrate appearance inspection device that inspects the appearance of flat portions and inclined portions of a three-dimensionally formed substrate 10 called a D substrate, that is, the defects of the flat portions and inclined portions. This optical substrate visual inspection device 1 is provided with a first light irradiation means 2, a second light irradiation means 3 provided below the first light irradiation means 2, and below the second light irradiation means 3. Third light irradiation means 4
And is provided above the first light irradiation means 2,
From the substrate 10 to the substrate 10 by the irradiation of light from the light irradiation means 2, the second light irradiation means 3, and the third light irradiation means 4.
It is composed of a monochrome CCD camera 5 which is an image pickup means for detecting the reflected light and the diffusely reflected light which are reflected in the vertical direction.

The first light irradiating means 2 emits a divergent light in a horizontal direction, and a collimator lens 22 which makes the divergent light emitted from the first light source 21 parallel light.
And a half mirror 23 having a reflecting surface arranged at 45 degrees with respect to the horizontal line and converting the parallel light parallelized by the collimator lens 22 into a direction orthogonal to the substrate 10, that is, a vertically downward direction. It consists of In this way, by making the divergent light parallel light by the collimator lens 22, it is possible to obtain the same illumination effect regardless of the position of the flat portion 11 of the substrate 10.

The second light irradiation means 3 is a half mirror 2.
This half mirror 23 is arranged between the substrate 3 and the substrate 10.
The light source support member 31 having a passage for passing the parallel light that has been vertically converted downward by the light source support member 31 and the end portions of the light source support member 31 corresponding to the upstream side and the downstream side in the transport direction of the substrate 10, respectively. , A second light source 3 for emitting divergent light
2 and 32.

A pair of the third light irradiating means 4 is provided between the second light irradiating means 3 and the substrate 10, and the third light irradiating means 4 intersects with the optical axis of the first light irradiating means 2 in parallel with the conveying direction of the substrate 10. It is axially symmetric with respect to the imaginary line and is arranged at the left and right positions on the upstream side of the substrate 10. Then, the third light irradiation means 4
It is configured such that parallel light can be irradiated toward each of the gradient portions 12 via an optical filter (not shown) that transmits light in a wavelength band having a low spectral reflectance on the surface of the base material portion of the substrate 10. There is. In this case, since the optical filter depends on the material of the base material and the purpose is to inspect for short-circuit defects due to the protrusion of gold plating on the gradient portion 12, a blue filter having a transmission wavelength band of 400 nm to 500 nm is adopted. It

More specifically, the direction of the optical axis of the irradiation light emitted from the pair of third light irradiation means 4, 4 is obliquely downward, and as shown in FIG. It is set so that the angle formed by the horizontal center line orthogonal to the transport direction passing through the center of the axis is 20 to 40 degrees (the angle formed by the optical axes is 100 to 140 degrees), and the angle is downward. A third light source 41 for irradiating light and a collimator lens 4 for collimating divergent light emitted from the third light source 41
2 and. By making the irradiation light parallel light by the collimator lens 42, the same illumination effect can be obtained regardless of the position of the gradient portion 12.

The third light irradiation means 4 and 4 are arranged in such an orientation that the specularly reflected light from the gradient portion 12 of the substrate 10 is not parallel to the vertical parallel light emitted from the first light irradiation means 2. This is to prevent adverse effects on the reflected light or the diffused reflected light that is emitted from the first light emitting means 2 and the second light emitting means 3 and is reflected vertically upward from the flat portion 11 of the substrate 10. Further, a blue filter having a transmission wavelength band of 400 nm to 500 nm is interposed as an optical filter in the third light irradiating means 4 in order to suppress the light amount of vertically upward diffused reflection light reflected by the gradient portion 12, and This is because, as will be described later, it is convenient for detecting a gold plating short circuit defect in the gradient portion 12.

Irradiation light is emitted from the first light irradiating means 2, the second light irradiating means 3, and the third light irradiating means 4, 4 toward the substrate 10, and the substrate 10 vertically upwards. The reflected light and the diffused reflected light are transmitted through the half mirror 23 and are incident on the monochrome CCD camera 5 provided above the half mirror 23.

The operation mode of the optical substrate visual inspection apparatus 1 according to the first embodiment will be described below with reference to FIG. 2A. From the second light sources 32, 32 of the second light irradiation means 3, Diffuse reflected light that is emitted obliquely downward, is reflected by the normal flat portion 11 of the substrate 10 and is incident on the monochrome CCD camera 5,
And the third light source 41 of each of the third light irradiation means 4 and 4,
The diffusely reflected light that is emitted obliquely downward from 41, is reflected by the normal gradient portion 12 of the substrate 10 and is incident on the monochrome CCD camera 5, is extremely small.

Therefore, according to the optical substrate visual inspection apparatus 1 according to the first embodiment, the light is emitted from the first light emitting means 2, is reflected by the flat portion 11 of the substrate 10 and is incident on the monochrome CCD camera 5. The light densities of the reflected light and the diffusely reflected light emitted from the second light irradiating means 3 and reflected from the substrate 10 differ depending on whether the light is reflected from the normal portion of the flat portion 11 or from the defective portion. That is, the density of the reflected light from the defective portion is either brighter at a higher density or darker at a lower density as compared with the average reflected light density of the normal portion. Lack,
It is possible to inspect for defects such as scratches and defective plating.

Further, in the case of the sloped portion 12 of the substrate 10,
Although the presence or absence of the short-circuit defect is mainly inspected, the short-circuit defect 14 of the gradient portion 12 can be detected by the scattered light emitted from the third light irradiation unit 4 and reflected from the substrate 10. In this case, the base material portion of the gradient portion 12 becomes a bright portion because scattered light enters the monochrome CCD camera, and the gold plating portion becomes a dark portion because light does not enter the monochrome CCD due to specular reflection. Therefore, as shown in FIG.
The short-circuit defect 14 in which the gold plating is projected on the base material portion 13 is detected as a dark portion. The irradiation direction of the irradiation light of the third light irradiation unit 4 and the optical filter suppress the light amount of the incident light incident on the monochrome CCD camera 5 from the substrate 10, so that the flat portion 11 and the gradient portion 12 of the substrate 10 are suppressed. And defects can be inspected at the same time.

Therefore, according to the optical substrate appearance inspection apparatus 1 according to the first embodiment, the appearance inspection work of the substrate 10 can be completed within a relatively short time as compared with the conventional example 1. Therefore, it can greatly contribute to the improvement of the productivity of the substrate 10. In addition, unlike the conventional example 2, since the appearance of the substrate is not inspected by utilizing the difference in the spectral reflectance of different materials, an object to be inspected having the same material but different surface shape, such as the MID substrate. It can greatly contribute to visual inspection.

Next, an optical substrate visual inspection apparatus according to the second embodiment of the present invention will be described. However, the difference between the second embodiment and the first embodiment is that an optical filter is not provided in the third light irradiating means and the function provided to the CCD camera is different. Other than that, the configuration is exactly the same, so the explanation will be limited to the functions given to the CCD camera.

The CCD camera is provided with an optical filter for separating the light incident on the CCD camera among the reflected light emitted from the first to third light emitting means and reflected by the substrate into red, green and blue. It is also a commercially available color CCD camera. Then, the captured red image, green image,
Among the blue images, the red image and / or the blue image detects defects in the flat portion of the substrate, while the green image detects defects in the inclined portion of the substrate.

That is, based on the captured image of white light,
The image of the first and second light irradiating means is created from the R wavelength and B wavelength components to detect defects in the flat portion of the substrate, while the image of the third light irradiating means is created from the G wavelength component. The defect of the gradient part is detected, and the defects of the flat part and the gradient part of the substrate can be detected at the same time. Therefore, the second embodiment has the same effect as the first embodiment.
However, in the second embodiment, as described above, the third
No optical filter is interposed in the light irradiation means. Therefore, the optical system of the optical substrate visual inspection device can be simplified, which can contribute to the compactness of the optical substrate visual inspection device.

[0025]

As described in detail above, the first aspect of the present invention
According to the optical substrate visual inspection apparatus of the second or second aspect, it is possible to simultaneously inspect for defects in the flat portion and the gradient portion of the three-dimensionally molded MID substrate. Therefore, the inspection work can be completed within a relatively short time as compared with the conventional example 1, which can greatly contribute to the improvement of the productivity of the substrate, and unlike the conventional example 2, it is different. Because it does not inspect the appearance of the substrate by utilizing the difference in the spectral reflectance of the material,
There is an excellent effect that it can greatly contribute to the appearance inspection of the inspection object having the different surface shape with the same material such as the MID substrate.

Further, according to the optical substrate visual inspection device of the third aspect of the present invention, it is not necessary to interpose an optical filter in the third light irradiation means, and the optical system of the optical substrate visual inspection device is simple. Since it can be realized, it can contribute to downsizing of the optical substrate visual inspection apparatus.

[Brief description of drawings]

1A and 1B relate to a first embodiment of the present invention, and FIG. 1A is a schematic side surface configuration explanatory diagram of an optical substrate visual inspection apparatus;
1B is a sectional view taken along the line AA of FIG.

FIG. 2 relates to the first embodiment of the present invention, and FIG. 2 (a) is a diagram showing the irradiation light emitted from the second light irradiation means and the irradiation light emitted from the third light irradiation means toward the CCD camera. FIG. 2B is a plan view of the substrate showing a defect state of gold plating.

[Explanation of symbols]

1 Optical substrate visual inspection device 2 First light irradiation means 3 Second light irradiation means 4 Third light irradiation means 5 CCD camera 10 substrates 11 Flat part 12 slope 13 Base material 14 Short circuit defect 21 First light source 22 Collimator lens 23 Half mirror 31 Light source support member 32 Second light source 41 Third light source 42 Collimator lens

Continued front page    (72) Inventor Yo Okamoto             1-5-5 Takatsukadai, Nishi-ku, Kobe City, Hyogo Prefecture             Kobe Steel Co., Ltd.Kobe Research Institute F term (reference) 2F065 AA56 BB02 CC01 DD06 FF04                       HH03 HH14 JJ03 JJ26 LL21                       UU01                 2G051 AA65 AB20 BA01 BA08 BB01                       BB07 CA04 CA06 CB01 CB05

Claims (3)

[Claims] 1. An optical substrate visual inspection apparatus for detecting a defect on a plated surface of a substrate by irradiating a substrate having a flat portion and a sloped portion with light and detecting reflected light from the substrate, First light irradiating means for irradiating the substrate with parallel light from a direction orthogonal to the substrate, second light irradiating means for irradiating the substrate with light in an oblique direction, and spectral reflection on the surface of the substrate portion of the substrate. An oblique direction in which an optical filter for transmitting light of a wavelength band having a low rate is interposed, and the reflected light from the gradient part of the substrate is not parallel to the parallel light emitted from the first light irradiating means with respect to the substrate. For irradiating parallel light from the at least one pair of third light irradiating means, which are arranged substantially in parallel with a virtual line intersecting the optical axis of the first light irradiating means in parallel with the transport direction of the substrate. From the first to third light irradiation means An optical substrate visual inspection apparatus comprising: an image pickup unit that detects reflected light and scattered light that are reflected in a direction orthogonal to the substrate when irradiated with light. 2. The optical filter is 400 nm to 50 nm.
The optical substrate inspection device according to claim 1, wherein the optical substrate inspection device is a blue filter that transmits light having a wavelength of 0 nm. 3. An optical substrate visual inspection apparatus for detecting a defect on a plating surface of a substrate by irradiating a substrate having a flat portion and a gradient portion on the surface with light and detecting reflected light from the substrate, First light irradiating means for irradiating the substrate with parallel light from a direction orthogonal to the substrate, second light irradiating means for irradiating the substrate with light in an oblique direction, and a gradient part of the substrate with respect to the substrate. In order to irradiate the parallel light from an oblique direction in which the reflected light from is not parallel to the parallel light emitted from the first light irradiating means, an optical axis of the first light irradiating means is parallel to the transport direction of the substrate. At least one pair of third light irradiation means, which are arranged substantially symmetrically with respect to the intersecting virtual line, and the light emitted from the first to third light irradiation means, are orthogonal to the substrate from the substrate. Reflected light and diffuse reflection It is characterized by comprising an image pickup means for separating light into red, green and blue, detecting a defect in the flat portion from a red or / and blue image, and detecting a defect in the gradient portion from a green image. Optical substrate visual inspection device.