JPH05258903A - Electronic parts - Google Patents

Abstract

(57) [Summary] [Object] To provide an electronic component capable of performing a visual inspection in a stable state by diffusing and reflecting the light for visual inspection, increasing the reflection output to the light receiving element. A component for diffusing and reflecting light such as silicon powder is arranged on the inner surface of a light-transmitting protective film 6 to form a light diffusing / reflecting portion 5. When the laser light is irradiated, the laser light is diffusely reflected by the light diffusing / reflecting portion 5, and a large amount of the reflected light is made incident on the light receiving element.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component suitable for mounting on a printed circuit board.

[0002]

2. Description of the Related Art After mounting electronic parts on a printed circuit board,
It is necessary to carry out visual inspections such as mounting / dismounting of electronic parts, misalignment, and horizontal standing.

The structure of a conventional electronic component and the principle of appearance inspection of the mounted state of the electronic component will be described below with reference to the drawings.

FIG. 7 is a partially cutaway perspective view showing a conventional electronic component. An electronic component 51 shown in FIG. 7 is a minute resistance element, in which a film-shaped resistor 53 is provided on the surface of a base 52 made of ceramic, and electrodes are formed on both ends of the base 52 so as to be connected to the ends of the resistor 53. 54 is provided. Resistor 5
The surface of No. 3 is covered with a protective film 55, and a symbol 56 for indicating the type is imprinted on the surface of the protective film 55.

FIG. 8 is an explanatory view of the principle of inspecting the state in which the electronic component 51 is mounted on the printed board 57 by the appearance inspection device. As shown in FIG. 8, the printed circuit board 57 on which the electronic component 51 is mounted is run in the direction perpendicular to the paper surface, and during this time, the laser light 58 is emitted from the laser light source (not shown) to the printed circuit board 57 and the electronic component 51. . The reflected light from the printed board 57 is made incident on the light receiving element 60 via the condenser lens 59. The reflected light from the protective film 55 of the electronic component 51 on the printed board 57 is also made incident on the light receiving element 60 via the condenser lens 59. Since the printed circuit board 57 and the electronic component 51 are different in the height of the reflection portion, the incident positions 61a and 61b of the reflected light with respect to the light receiving element 60 are different, and the light receiving element 60 electrically detects the difference dx between the positions 61a and 61b. And the height dimension of the electronic component 51 is read. Based on such a principle, it is possible to perform an appearance inspection such as presence / absence of the electronic component 51, misalignment, and horizontal standing.

[0006]

However, in the conventional electronic component 51 as described above, when the laser light 58 is irradiated, the laser light 58 is specularly reflected on the surface portion of the protective film 55 with almost no diffuse reflection. As a result, the reflected output of the laser light 58 to the light receiving element 60 is reduced or halation occurs, and there is a problem that the appearance inspection cannot be reliably performed in a stable state.

The present invention solves such a conventional problem, and diffuses and reflects the light for appearance inspection, increases the reflection output to the light receiving element, and can reliably perform appearance inspection in a stable state. The object is to provide an electronic component that can be manufactured.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention comprises a light diffusing / reflecting portion capable of diffusing and reflecting light for visual inspection.

As the light diffusing / reflecting portion, a component for diffusing and reflecting light is formed on the back surface of the light transmitting protective film, or a component for diffusing and reflecting light is arranged on the surface of the protective film. It can be formed by forming a component that diffuses and reflects light inside a light-transmitting protective film, or by roughening the surface of the protective film, or by an exposed surface of a ceramic.

[0010]

Therefore, according to the present invention, since the light diffusing / reflecting portion is provided, when the light for visual inspection is irradiated, it is diffused and reflected by the light diffusing / reflecting portion and a large amount of reflected light is made incident on the light receiving element. You can

[0011]

【Example】

(Embodiment 1) Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing an electronic component according to the first embodiment of the present invention. The electronic component 1 shown in FIG. 1 is a minute resistance element, in which a film-shaped resistor 3 is provided on the surface of a base body 2 made of ceramic, and electrodes are formed on both ends of the base body 2 so as to be connected to the ends of the resistor 3. 4 are provided. The surface of the resistor 3 is provided with a light diffusing and reflecting portion 5 made of a component such as silicon powder that diffuses and reflects light, and the surfaces of the light diffusing and reflecting portion 5 and the electrode 4 are covered with a protective film 6. That is, the light diffuse reflection portion 5 is formed by arranging a component that diffuses and reflects light on the back surface of the protective film 6. Therefore, the protective film 6 is formed of a light transmissive material.

The appearance inspection operation of the mounted state of the electronic component 1 configured as described above will be described with reference to the principle explanatory diagram shown in FIG.

The printed circuit board 7 on which the electronic component 1 is mounted is run in a direction perpendicular to the paper surface, and during this time, a laser light source (not shown) irradiates the printed circuit board 7 and the electronic component 1 with laser light 8. At this time, in the electronic component 1,
The laser light 8 passes through the protective film 6, is diffused and reflected by the light diffusing and reflecting portion 5, and a large amount of reflected light is incident on the light receiving element 10 via the condenser lens 9. Therefore, the height dimension of the electronic component 1 can be read in the same manner as the above-mentioned conventional example, and the appearance inspection of the electronic component 1 such as presence / absence, displacement, and standing can be performed.

(Second Embodiment) A second embodiment of the present invention will be described below with reference to the drawings.

FIG. 3 is a sectional view showing an electronic component according to the second embodiment of the present invention. In the present embodiment, as shown in FIG. 3, the light diffusion reflection portion 5 is formed on the surface of the protective film 6 by disposing a component such as silicon powder that diffuses and reflects light. Therefore, the protective film 6 in this embodiment does not need to be light transmissive. The other parts of the configuration are the same as those of the first embodiment, and therefore, the same parts are designated by the same reference numerals and the description thereof is omitted.

(Embodiment 3) A third embodiment of the present invention will be described below with reference to the drawings.

FIG. 4 is a sectional view showing an electronic component according to the third embodiment of the present invention. In this embodiment, as shown in FIG. 4, a light diffusion reflection part 5 is formed by arranging a component such as silicon powder that diffuses and reflects light inside a protective film 6 made of a light transmissive material. Since the other configurations are similar to those of the first embodiment, the same parts are designated by the same reference numerals and the description thereof will be omitted.

(Embodiment 4) A fourth embodiment of the present invention will be described below with reference to the drawings.

FIG. 5 is a sectional view showing an electronic component according to the fourth embodiment of the present invention. In the present embodiment, as shown in FIG. 5, the light diffusion reflection portion 5 is formed with the surface of the protective film 6 roughened. Therefore, the protective film 6 in this embodiment is made of a light-reflecting material. The rest of the configuration is the same as that of the first embodiment described above, so the same reference numerals are given to the same parts and the description thereof is omitted.

(Fifth Embodiment) A fifth embodiment of the present invention will be described below with reference to the drawings.

FIG. 6 is a sectional view showing an electronic component according to the fifth embodiment of the present invention. In the present embodiment, as shown in FIG. 6, the exposed surface of the base body 2 made of ceramic is used as the light diffusing and reflecting portion 5. Since ceramic easily diffuses and reflects light, it can be used as it is as the light diffusing and reflecting portion 5. The other parts of the configuration are the same as those of the first embodiment, and therefore, the same parts are designated by the same reference numerals and the description thereof is omitted.

[0023]

As described above, according to the present invention, since the light diffusing / reflecting portion is provided, when the light for visual inspection is irradiated, it is diffused and reflected by the light diffusing / reflecting portion to receive a large amount of reflected light. It can be incident on the device. Therefore,
Appearance inspection can be reliably performed in a stable state.

[Brief description of drawings]

FIG. 1 is a sectional view of an electronic component according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of the appearance inspection principle of the mounted state of the electronic component.

FIG. 3 is a sectional view of an electronic component according to a second embodiment of the present invention.

FIG. 4 is a sectional view of an electronic component according to a third embodiment of the present invention.

FIG. 5 is a sectional view of an electronic component according to a fourth embodiment of the present invention.

FIG. 6 is a sectional view of an electronic component according to a fifth embodiment of the present invention.

FIG. 7 is a partially cutaway perspective view of a conventional electronic component.

FIG. 8 is an explanatory diagram of the appearance inspection principle of the mounted state of the electronic component.

[Explanation of symbols]

 1 Electronic Component 2 Base 3 Resistor 4 Electrode 5 Light Diffuse Reflecting Part 6 Protective Film

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takumi Sudo Door 4-3-1, Tsunashima-higashi, Kohoku-ku, Yokohama-shi, Kanagawa Matsushita Communication Industrial Co., Ltd. 3-3-1 Matsushita Communication Industrial Co., Ltd.

Claims (6)

[Claims] 1. An electronic component having a light diffusion reflection portion capable of diffusely reflecting light for visual inspection. 2. The electronic component according to claim 1, wherein the light diffusing and reflecting portion is formed by arranging a component for diffusing and reflecting light on the back surface of the light transmitting protective film. 3. The electronic component according to claim 1, wherein the light diffusing and reflecting portion is formed by arranging a component for diffusing and reflecting light on the surface of the protective film. 4. The electronic component according to claim 1, wherein the light diffusing / reflecting portion is formed by arranging a component that diffuses and reflects light inside a light-transmitting protective film. 5. The electronic component according to claim 1, wherein the light diffuse reflection portion is formed by roughening the surface of the protective film. 6. The electronic component according to claim 1, wherein the light diffuse reflection portion is an exposed surface of ceramic.