KR100484655B1 - Line scan camera using penta-prism - Google Patents

Abstract

A line scan camera using a pentaprism is provided to reduce a working distance, thereby enhancing space utilization, and simplify an inner structure to have a small weight, thereby being unaffected by vibration. A line scan camera has an image acquiring unit(401), a focus controlling unit having two convex lenses(402) and a diaphragm(403) between the two lenses, and an image converting unit(404). The image acquiring unit acquires a line scan image of a panel. The focus controlling unit controls a focal distance to reduce the working distance between the image acquiring unit and the panel. A pentaprism is capable of being used in the image converting unit. A CCD(Charge Coupled Device) is capable of being used in the image acquiring unit. The image converting unit converts the angle of the light from the focus controlling unit to exit the converted light to the panel. The image converting unit rotates the line scan image from the panel to transfer the rotated line scan image to the image acquiring unit. Herein, the rotated line scan image is photographed by the image acquiring unit having a long axis and a short axis reversed each other.

Description

Line scan camera using penta-prism}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a line scan camera, and more particularly, to a line scan camera used to inspect an edge surface of a panel such as a liquid crystal display device.

In general, a liquid crystal display (LCD) displays a display in which a desired image can be displayed by individually supplying data signals according to image information to liquid crystal cells arranged in a matrix to adjust light transmittance of the liquid crystal cells. Device.

The liquid crystal display device forms a thin film transistor array substrate (TFT) on a large mother substrate, forms color filter substrates (CF) on a separate mother substrate, and then bonds the two mother substrates together. Since the panels are formed simultaneously to improve the yield, a step of cutting the unit liquid crystal panel is required.

In general, the cutting of the unit panel is performed through a process of forming a cutting scheduled groove on the surface of the mother substrate with a wheel that is harder than glass and allowing cracks to propagate along the cutting scheduled groove.

When the unit liquid crystal panel is separated, a phenomenon such as burrs, cracks, and pattern cracks may occur on the edge surface cut through the cutting process. When burrs are generated on the edge surface during this phenomenon, serious defects may occur in the manufacturing process equipment of the next liquid crystal panel, and thus the liquid crystal panel edge surface is inspected after the cutting process for separating the liquid crystal panel.

In order to inspect the edge surface of a liquid crystal panel, it measured conventionally by touching an edge surface mechanically. That is, by using a means having a sensor on one side to contact the edge surface of the liquid crystal panel with one side provided with the sensor to check the burrs, cracks and pattern cracks generated on the edge surface.

However, when the edge surface of the liquid crystal panel is inspected by the conventional mechanical contact method, it is not possible to inspect that the edge defect is formed inside a constant reference line, and in particular, there is a problem in that no damage is detected in the pattern.

In order to overcome this problem, an inspection method of an edge using optics has been introduced. In the edge inspection method using optics, an image of an edge surface is acquired using a line scan camera, and the necessary dimensions and defects are determined through image processing of the acquired image.

A line scan camera for capturing an image of the edge surface of the liquid crystal panel will be described with reference to FIG. 1.

Referring to FIG. 1, line scan cameras 30, 40, 50, and 60 are positioned to capture an image along upper and lower edges of the panel 10 mounted on the table 20. Illuminations 31, 41, 51, 61 are provided at 30, 40, 50, and 60. The line scan camera is provided with the line scan cameras 30 and 40 positioned above the panel 10 and the line scan cameras 50 and 60 positioned below the line scan camera. Each of the line scan cameras 30, 40, 50, and 60 and the lights 31, 41, 51, and 61 are controlled by the central computer for image acquisition and brightness of the lights. In order to obtain a high quality image, it is very important to adjust the lighting appropriately, and in FIG. 1, the position of the lighting is shown together with the camera. However, the position of the lighting and the angle brightness are various for obtaining an optimal image as necessary. It is determined by one attempt.

The upper edge surface is imaged by the upper cameras 30 and 40 while the panel 10 mounted on the table 20 moves, and the lower edge surface is imaged by the lower cameras 50 and 60.

The line scan camera will be described in more detail with reference to FIGS. 2A and 2B.

2A is a side cross-sectional view of the line scan camera of FIG. 1.

Referring to FIG. 2A, since the depth of the line scan camera 30 increases as the end of the CCD and the lens increases, the length of the overall camera body should be long. Therefore, the working distance between the camera and the panel becomes long. The line scan camera 30 of FIG. 2A has a length of a body installed vertically from the panel 10 and the innermost position of the line scan camera 30 is located farthest from the panel 10. The CCD 310 is installed in this. In addition, the conversion unit 320 and two telephoto rings (extender rings), the first telephoto ring 330 and the second telephoto ring 340 are installed below. The lower portion of the two telephoto rings includes a lens unit 350 having a plurality of lenses. The CCD 310 of the line scan camera 30 is for capturing an image of the panel 10, and the conversion unit 320 is connected to the front or rear of the lens unit to adjust the overall focal length. Accordingly, the position of the conversion unit 320 is not limited to FIG. 2A shown. In addition, the first telephoto ring 330 and the second telephoto ring 340 are provided below the conversion unit 320 and installed to increase the working distance. The lens unit 350 includes a plurality of lenses, for example, an iris lens for adjusting brightness and a focus lens for focusing.

The line scan camera 30 captures a line scan image along the edge surface of the panel 10. That is, the CCD image and the line scan image of the CCD 310 of the line scan camera 30 are formed on the line scan axis in the same manner. That is, the line scan camera 30 is line scanned such that the long axis and short axis of the line scan image of the panel 10 are the same as the CCD image formed on the CCD 310. The CCD image refers to an image formed on the CCD 310 surface.

FIG. 2B is a plan view of such a line scan camera, showing the line scan camera 30 on top of the panel 10.

Referring to FIG. 2B, the line scan camera 30 is shown above the panel 10 and the panel 10, and the CCD 310 is shown inside the line scan camera 30. The line scan image 100 can be obtained along the line scan direction of the panel 10, and the movement direction of the line scan camera is such that the long axis and the short axis of the line scan image 100 are the same as the CCD image formed on the CCD 310. Is set. That is, the line scan direction and the movement direction of the line scan camera of the CCD 310 are the same, and in this case, the CCD image of the line scan camera 30 is the same as that of the line scan image 100 of the panel 10. Is imaged.

However, such a conventional line scan camera has a long working distance, so the configuration is complicated, the weight is heavy, and the body is long, so that the space utilization is inferior during installation. There is a problem of less usability.

In addition, since the focal length is increased in order to lengthen the working distance, it is difficult to focus and there is a problem of blurring toward the edge of the line-by-line image acquired by the line scan camera.

Therefore, the object of the present invention is to minimize the configuration of the camera to solve the above-mentioned problems, it is possible to make the camera body small by shortening the working distance is excellent space utilization, as well as the upper camera of the panel as well It is to provide a line scan camera using a penta prism that can also be replaced with a camera.

The line scan camera according to the present invention for achieving the above object is a line scan camera for photographing a panel, the image acquisition means for acquiring the line scan image of the panel, the working distance between the image acquisition means and the panel is short Focus adjusting means for adjusting the focal length so that the focus distance, and the incident light from the focus adjusting means is angularly converted to the panel and the line scan image obtained from the panel is rotated at right angles so that the long axis and short axis of the line scan image are interchanged with each other. And image conversion means for imaging on the means.

In addition, according to the present invention, the focus adjusting means is characterized in that it comprises an aperture between the two convex lenses, and two convex lenses.

In addition, according to the present invention, the image conversion means is characterized in that the five-sided prism of the prism.

In addition, according to the present invention, the prism is characterized by converting the incident light to a 90-degree angle is emitted.

In addition, according to the present invention, the prism is characterized in that the pentaprism.

In addition, according to the present invention, the image acquisition means is characterized in that the CCD.

According to the present invention, the CCD image picked up by the CCD has a long axis in the line scan direction and the line scan camera moving direction.

Further, according to the present invention, the line scan image has a long axis in the line scan direction, and the CCD image has a long axis in the line scan direction.

According to the present invention, the line scan image and the CCD image are orthogonal to each other when the line scan direction and the line scan camera movement direction are the same direction.

Hereinafter, with reference to the accompanying Figures 3 to 5 will be described in detail a preferred embodiment of the present invention.

Before describing the line scan camera using the pentaprism of the present invention, the principle of the pentaprism will be described first.

3 is a view for explaining the principle of such a pentaprism.

Reference numeral 15 in FIG. 3 denotes a pentaprism. Pentaprism has five sides and the top has two slopes, like an arch roof. The etymology of pentaprism comes from the Latin prefix penta-, meaning pentagonal five. Pentaprism is also called 'eye level finder' because it can see the viewfinder at eye level.

Referring to the principle of the pentaprism 15 of FIG. 3, the light entering through the lens L is reflected perpendicularly to the built-in mirror 12. The reflected light enters the bottom of the pentaprism 15 and is reflected on the first surface of the top of the pentaprism 15 so that the reversed phase is correctly corrected. Then, it is reflected at right angles and after two more reflections, the angle is changed and emitted. Therefore, when the image inverted in the mirror 12 passes through the pentaprism 15 again, it is seen as top, bottom, right and left normal.

In FIG. 3, the light to be transmitted through the photographing lens 11 is collected on the in-plane focus plate 14 such as the image area 13 through the mirror 12 to form the subject image. The photographer observes the subject image through the pentagram prism 15 and the eyepiece (eyepiece system) 16.

4 is a side view illustrating a line scan camera using a pentaprism according to an embodiment of the present invention.

Referring to FIG. 4, the line scan camera 400 has a length of the body installed in the horizontal direction from the panel 10 in a long direction, and when looking at the internal structure in the order of the working distance along the path of light, the panel is located in a long distance. The CCD 401 is provided at the position furthest from the light path from 10. The lens unit 402 and the diaphragm 403 and a pentaprism 404 for converting the incident light and the outgoing light by 90 degrees to the left.

The pentaprism 404 of FIG. 4 has five faces as described above with respect to FIG. 3. Three of them are reflecting surfaces on which light is reflected, one is an incidence surface on which light is incident, and the other is an emission surface on which light reflected from the reflection surface is emitted. That is, the light coming from the incident surface is reflected at right angles from the first reflecting surface and is reflected toward the second reflecting surface adjacent to the first reflecting surface, and the light reflected from the second reflecting surface is the first reflecting surface adjacent to the second reflecting surface. It is reflected from the 3rd reflection surface and heads toward the exit surface. Therefore, the light reflected from the third reflection surface passes through the emission surface to form a light spot on the panel 10. Light reflected from the panel 10 is captured on the CCD 401 through a reverse process. In this case, an aperture 403 and a lens unit 402 are formed between the CCD 401 and the pentaprism 404 to adjust the focal length so as to shorten the working distance for obtaining the line scan image 110 from the panel. An optical spot is formed at 10 and the imaging light reflected from the panel 10 is transferred to the CCD 401.

Although the line scan camera 400 having the pentaprism 404 has been described as a camera on the upper side, when installed downward, the line scan camera 400 of FIG. 4 is rotated 180 degrees to be installed at the bottom of the panel 10. Is possible. In addition, the line scan camera 400 of FIG. 4 has a small number of internal components and employs a pentaprism, and thus a short working distance. Therefore, it is possible to install both on the top and bottom of the panel in the space utilization surface. And since the weight is light, it is also resistant to vibration, so it is also possible to move the position of the camera to take an image of the edge surface of the panel.

5 is a plan view illustrating a line scan camera using a pentaprism according to an embodiment of the present invention.

Referring to FIG. 5, line scan images 110, 120, and 130 for capturing an image A on the panel 10 are illustrated. The line scan images 110, 120, and 130 are sequentially picked up along the line scan direction (arrow display). In FIG. 5, the line scan camera 400 is a plan view seen from above, and the CCD 401 has a long axis of vertical axis that is vertically long. In order to obtain the line scan image, the line scan camera 400 is moved to the upper portion of the panel 10, and the line scan camera 400 is moved along the line scan camera moving direction to transfer the line scan images to the CCD 401 in order. Acquire a CCD image. The line scan image having the long axis in the horizontal direction is rotated at right angles while passing through the pentaprism 404, and the CCD image is captured to have the long axis in the vertical direction in the CCD 401.

Although the line scan camera 400 disclosed in FIG. 4 and FIG. 5 has been described as employing a pentaprism, the line scan camera 400 may be implemented in another configuration in which the incident light is converted by 90 degrees.

Therefore, the line scan camera of the present invention is equipped with a penta prism, the working distance is shortened, so the space utilization is increased, and the internal structure is simplified, the weight is light, thereby providing the effect of being insensitive to vibration.

In addition, the volume of the line scan camera is reduced, so that shooting from various angles is possible, and it is also possible to obtain an image of the panel by moving the camera.

In addition, since the panel can be used for the top and bottom of the panel at the same time, the usability is increased.

1 is a view for explaining a general line scan camera,

Figure 2a is a side view of the line scan camera used in Figure 1

2B is a plan view of the line scan camera used in FIG.

3 is an exemplary view for explaining the principle of pentaprism used in the present invention,

4 is a side view for explaining a line scan camera using a pentaprism according to an embodiment of the present invention;

5 is a plan view illustrating a line scan camera using a pentaprism according to an embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

400: line scan camera 401: CCD

402: lens 403: aperture

404: pentaprism 110, 120, 130: line scan image

Claims (9)

In the line scan camera for photographing the panel, Image acquisition means for acquiring a line scan image of the panel; Focus adjusting means for adjusting a focal length so that the working distance between the image acquisition means and the panel is shortened; And An image conversion means for converting the incident light from the focus adjusting means to be outputted to the panel and rotating the line scan image obtained from the panel at a right angle so that the long axis and the short axis of the line scan image are interchanged so as to be captured by the image acquisition means; Line scan camera comprising a. The method of claim 1, The focus adjusting means And a convex lens between the two convex lenses and the two convex lenses. The method of claim 1, The image converting means is a line scan camera, characterized in that the five-sided prism of the five sides. The method of claim 3, wherein The prism is a line scan camera, characterized in that for converting the incident light to an angle of 90 degrees. The method of claim 4, wherein And the prism is a pentaprism. The method according to any one of claims 1 to 5, And said image acquisition means is a CCD. The method of claim 6, And a CCD image picked up by the CCD has a long axis in a line scan direction and a line scan camera movement direction. The method of claim 7, wherein And wherein the line scan image has a long axis in the line scan direction, and the CCD image has a long axis in the line scan direction. The method of claim 8, And the line scan image and the CCD image are orthogonal to each other when the line scan direction and the line scan camera movement direction are the same direction.