JP2004109127A - Defect detection device for fpd substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a defect detection device for an FPD (flat panel display) substrate, which facilitates the inspection of a large substrate, reduces the volume, reduces the manufacture cost, and can shorten the inspection time of the substrate. <P>SOLUTION: The defect detection device for the FPD substrate includes a light source; a focusing lens for concentrating the light emitted from the light source; and a polygon mirror which the light transmitted through the focusing lens enters, diffused, and reflected, or includes the light source; an optical guide plate which the light emitted from the light source enters and diffused; and an optical transmission means for transmitting the light emitted from the light source to the optical guide plate. Accordingly, since the large substrate can be easily inspected and there is no need for a long optical path, the dimension of the inspection device can be reduced. Further, since there is no need for varying the irradiation position with the light, the cost for constructing a control part or the like is saved, and the manufacturing cost can be reduced. The inspection time can be shortened, thus improving the productivity. <P>COPYRIGHT: (C)2004,JPO

Description

The present invention relates to a defect inspection apparatus for an FPD substrate, and more particularly to a macro inspection apparatus used for inspecting a surface defect of an FPD substrate.

In response to the development of information and communication technology and the demands of the diversified information society, the demand for electronic displays is increasing, and the required displays are also diversifying, and new flat panel displays (Flat Panel Displays, , 'FPD') devices are being developed one after another. Currently, flat panel displays under development or production include liquid crystal display elements (Liquid Crystal Display: LCD), organic electroluminescence display elements (Organic Electroluminescence Display: OELD), plasma display elements (Plasma Display Panel: PDP) and light emitting diodes ( Light Emitting Display (LED).

In order to maintain the above-mentioned stable quality of FPDs, the development of materials and the development of processes are also important.However, if there is a defect in the substrate such as glass or plastic used for their production, No. A device for inspecting a defect of an FPD substrate includes irradiating the substrate surface with light and inspecting the substrate surface for defects based on an optical change of the light, and a defect portion detected by the macro inspection. There is a micro inspection device for inspecting by enlarging.

FIG. 1 is a schematic diagram for explaining a conventional FPD macro inspection apparatus.
Referring to FIG. 1, a conventional FPD macro inspection apparatus includes a light source 10, mirrors 21 and 22 provided to sufficiently secure an optical path of light emitted from the light source 10, and a diffuser through the mirrors 21 and 22. A Fresnel lens (Fresnel lens) 30 for collecting the light, and a liquid crystal plate 40 for scattering or condensing the light passing through the Fresnel lens 30. Therefore, the light emitted from the light source 10 passes through the mirrors 21 and 22, the Fresnel lens 30, and the liquid crystal plate 40 in order, and is applied to the FPD substrate, which is the subject, and is reflected. The presence or absence of a defect such as a scratch or unevenness is determined.

FIG. 2A is a schematic diagram for explaining the progress of light before and after the Fresnel lens in the conventional FPD macro inspection apparatus shown in FIG. 1, and FIG. 2B is a schematic view showing the light using the FPD macro inspection apparatus shown in FIG. FIG. 4 is a schematic diagram showing the brightness of the FPD substrate when the light is irradiated.

As shown in (1) and (2) of FIG. 2A, in order for the light passing through the Fresnel lens 20 to be sufficiently spread by the area of the substrate as the subject, the distance between the light source 10 and the Fresnel lens 30 must be increased. Need to be long. This is the reason for sufficiently securing the optical path of the light using the mirror in FIG.

Then, as shown in (2) of FIG. 2A, when the light is collected, the illuminance on the FPD substrate and the luminance at the position of the inspector become high. Requires that the size of the Fresnel lens 30 be large.

Therefore, in order to compensate for insufficient brightness using a Fresnel lens, the optical path between the light source and the Fresnel lens and the size of the Fresnel lens must be considered. However, to increase the optical path between the light source and the Fresnel lens and to increase the size of the Fresnel lens, there is a limit such as the size of the equipment and the unit production cost increases. It is not suitable for the current trend of increasing size. In order to overcome this, the light source, mirror, Fresnel lens, etc. may be moved to change the light irradiation position, but this will increase the construction cost of the control unit and increase the inspection time. There is a problem.

On the other hand, referring to the brightness of the FPD substrate shown in FIG. 2B, the conventional inspection apparatus shown in FIG. 1 has a structure in which only a single light source is used. The appearance of darkening appears. Such uneven brightness on the substrate makes it impossible to accurately determine the presence or absence of a defect.

Therefore, the technical problem to be solved by the present invention is to easily inspect large substrates, to reduce the volume, to reduce the manufacturing cost, and to reduce the inspection time of the FPD substrate. An object of the present invention is to provide a defect inspection device.

According to one embodiment of the present invention, there is provided an apparatus for inspecting a defect of an FPD substrate for solving the above technical problem, comprising: a light source; a focusing lens provided on an optical path of light emitted from the light source to focus the light; And a polygon mirror for receiving the light transmitted through the focusing lens and diffusing and reflecting the light in the direction in which the FPD substrate as the subject is placed.

According to another embodiment of the present invention, there is provided an apparatus for inspecting a defect of an FPD substrate according to another embodiment of the present invention, comprising: a light source; light emitted from the light source being incident thereon; And a light transmitting means for transmitting light emitted from the light source to the light guide plate.

As described above, according to the FPD substrate defect inspection apparatus of the present invention, a large substrate can be inspected.

Also, unlike the prior art, it is not necessary to lengthen the optical path, so the size of the inspection device can be reduced, and since there is no need to change the light irradiation position, the construction cost of the control unit is reduced, The unit production cost of the device can be reduced.

Furthermore, since it is not necessary to change the light irradiation position, the inspection time can be shortened and the productivity is improved.

The present invention is not limited to only the above-described embodiment, but it is apparent that various modifications can be made by those having ordinary knowledge in the relevant field within the technical idea of the present invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

FIGS. 3A and 3B are schematic views illustrating an apparatus for inspecting a defect of an FPD substrate according to a first embodiment of the present invention, and FIG. 4 is a schematic view illustrating a defect of the FPD substrate according to a second embodiment of the present invention. It is a schematic diagram for explaining an inspection device.

[Example 1]
Referring to FIG. 3A, the apparatus for inspecting defects of an FPD substrate according to the present embodiment includes a light source 10, a focusing lens 110, and a polygon mirror 120.

光 As the light source 10, a light halogen lamp or a metal halide lamp is used.

The focusing lens 110 is provided on the optical path of the light emitted from the light source 10. Therefore, when the light emitted from the light source 10 is incident on the focusing lens 110, it is converged into a thin strip of parallel light and transmitted through the focusing lens 110.

The polygon mirror 120 is rotatably provided on the optical path of the converged light transmitted through the focusing lens 110. Therefore, when the condensed light transmitted through the focusing lens 110 is incident on the polygon mirror 120, it is diffused and reflected in the form of a surface light source by the polygon mirror, and is irradiated on the surface of the FPD substrate.

The polygon mirror 120 is an optical component made of a polyhedron having mirror surfaces of the same size. A point light source such as a laser beam incident on the polygon mirror by the rotation of the polygon mirror is diffused and reflected by the line light source, and the line light source is diffused and reflected by the surface light source. As shown in FIG. 3A, one surface light source is created per one mirror surface of the polygon mirror, so that the number of surface light sources equal to the number of mirror surfaces is created per one rotation of the polygon mirror. By the way, human eyes recognize as continuous light when light is illuminated 24 times or more per second. Therefore, when the polygon mirror 120 is assumed to be an octahedron, if it is rotated only three times or more per second, a person perceives that the surface light source is always illuminated on the FPD substrate.

Therefore, the light emitted from the light source 10 passes through the focusing lens 110 and the polygon mirror 120 in order, and is applied to the FPD substrate, which is the subject, in the form of a surface light source. The presence or absence of a defect such as a scratch or unevenness is determined.

As described above, by inspecting the FPD substrate for defects using the surface light source irradiated from the polygon mirror 120, the light irradiation area can be increased only by adjusting the number of mirror surfaces and the rotation speed of the polygon mirror. Therefore, a large substrate can be easily inspected, and unlike the related art, it is not necessary to lengthen the optical path, so that the size of the inspection apparatus can be reduced. Further, since it is not necessary to change the light irradiation position, the construction cost of the control unit and the like can be reduced, and the inspection time can be shortened.

On the other hand, as shown in FIG. 3B, a Fresnel lens 130 is further provided on the optical path of the light diffused and reflected from the polygon mirror 120 so that the surface light source irradiated on the substrate is uniformly collected. The light diffused and reflected from the substrate may be applied to the surface of the substrate via the Fresnel lens 130.

If necessary, a color filter (not shown) may be further provided in front of or behind the polygon mirror 120 so that light incident on the polygon mirror or light reflected from the polygon mirror becomes monochromatic light. Good.

[Example 2]
Referring to FIG. 4, the apparatus for inspecting an FPD substrate for defects according to the present embodiment includes an optical transmission unit including a light source 10, a light guide plate 210, and an optical fiber bundle 220.

The optical fiber bundle 220 is provided so that the light emitted from the light source 10 is uniformly transmitted to the light guide plate 210. That is, one end of each of the optical fibers 221 is provided inside the light guide plate 210 so as to form a lattice arrangement at a constant interval, and the other end is provided to face the light source 10.

Therefore, the light emitted from the light source 10 is incident on the light guide plate 210 through the optical fiber 221, is diffused, and is irradiated on the FPD substrate so that the inspector can determine whether there is a defect such as a scratch or unevenness. Become.

Thus, by simply arranging the optical fibers 221 such that the light transmitted by the optical fibers 221 is evenly distributed over the entire surface of the light guide plate 210, the illumination required for inspecting the substrate for defects can be obtained. Therefore, the inspection device can be implemented extremely simply and economically as compared with the conventional one.

On the other hand, in order to increase the luminous efficiency, a light collecting means (not shown) may be further provided between the light source 10 and the other end of the optical fiber bundle 220.

It is a schematic diagram for explaining the conventional FPD macro inspection device. It is a schematic diagram for explaining the conventional FPD macro inspection device. It is a schematic diagram for explaining the conventional FPD macro inspection device. FIG. 2 is a schematic view illustrating an apparatus for inspecting defects of an FPD substrate according to an embodiment of the present invention. FIG. 2 is a schematic view illustrating an apparatus for inspecting defects of an FPD substrate according to an embodiment of the present invention. FIG. 2 is a schematic view illustrating an apparatus for inspecting defects of an FPD substrate according to an embodiment of the present invention.

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 10 ... Light source 110 ... Focusing lens 120 ... Polygon mirror 130 ... Fresnel lens 210 ... Light guide plate 220 ... Optical fiber bundle 221 ... Optical fiber

Claims (5)

A light source;
A focusing lens provided on an optical path of the light emitted from the light source and focusing the light;
A defect of the FPD substrate including: a polygon mirror that is rotatably provided, receives light transmitted through the focusing lens, and diffuses and reflects the incident light in a direction in which the FPD substrate serving as a subject is placed. Inspection equipment. A Fresnel lens is further provided on the optical path of the light reflected from the polygon mirror, so that the light diffused and reflected from the polygon mirror is uniformly collected and applied to the surface of the FPD substrate. The defect inspection apparatus for a substrate for an FPD according to claim 1, wherein: 2. The color filter according to claim 1, further comprising a color filter that is provided in front of or behind the polygon mirror and that converts light incident on the polygon mirror or light reflected from the polygon mirror into monochromatic light. 3. The defect inspection apparatus for an FPD substrate according to 2. A light source;
A light guide plate on which light emitted from the light source is incident and which diffuses the incident light in a direction in which an FPD substrate as an object is placed;
A light transmission unit for transmitting light emitted from the light source to the light guide plate; The optical transmission means,
An optical fiber bundle, one end of the optical fiber is provided in the light guide plate so as to form a lattice arrangement at a fixed interval, the other end is an optical fiber bundle provided to face the light source. The apparatus for inspecting defects of an FPD substrate according to claim 4, wherein:

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