KR100911331B1 - Array tester and method for measuring a point of substrate of the same - Google Patents

Abstract

An array tester and a method for measuring a point of substrate of the same are provided to a certain position accurately by reducing an error in teaching. A test apparatus(10) comprises a test module(50), a test block(30), and a position display member(200). A loading unit comprises more than two loading plates(22), and a substrate(2) is supported by the substrate chuck(70) and is transferred to the test block. A test block comprises a stage(32) for test and voltage supply unit(38), and the test module comprises more than one modulator head(100). The modulator head comprises a fixed block(110), a camera assembly(120), and a modulator block(130).

Description

Array tester and method for measuring a substrate point position of the array test device {Array tester and method for measuring a point of substrate of the same}

The present invention relates to an array test apparatus, a method of measuring a substrate point position of the array test apparatus, and more particularly, an array test apparatus for inspecting an electrical defect of electrodes formed on a substrate as a plurality of cameras, and the array test. A method for measuring a substrate one point position of an apparatus.

An all-optical device is a device that emits light by receiving electric energy, and includes a flat display device such as an LCD (Liquid Crystal Display) and a Plasma Display Panel (PDP).

The all-optical device typically has a substrate on which electrodes are formed. For example, a TFT (Thin Film Transister) LCD substrate may include a TFT substrate, a color substrate having color filters and a common electrode disposed to face the TFT substrate, a liquid crystal and a backlight injected between the TFT substrate and the color substrate. Equipped.

Defects of the electrodes formed on the substrate are inspected by an array tester. The array test apparatus has at least one modulator head. The modulator head locates a defective position of the substrate electrode while being transferred in at least one direction, and includes a modulator block and a camera.

The modulator block includes a modulator electrode for forming an electric field between the substrate electrode and a physical property change portion whose physical properties change according to the size of the electric field. The modulator block performs an array test on a portion of the substrate and then moves to the next adjacent test location to repeat the array test.

The camera is disposed opposite the substrate of the modulator block to photograph the modulator block and the substrate. As the physical properties change in the physical property changing unit, a pixel photographed by the camera at a defective point among substrate electrodes is different from other pixels. Accordingly, the position of the defective electrode is found by the position coordinate value of the pixel of the camera.

However, a single camera is provided for each modulator head. Accordingly, the size of the field of view (FOV) of the camera is limited.

In particular, with the trend that the size of the display is enlarged, in order to quickly detect whether or not the substrate electrode of the display is defective, a camera having an increasingly larger FOV is required, but this is not practical.

In addition, as the size of the camera increases, a large driving power is required, and the camera cost also increases exponentially.

 Accordingly, an object of the present invention is to provide an array test apparatus in which an FOV photographed at a time has a structure in which the size thereof can be adjusted according to the size of a display, and a large driving power is unnecessary and manufacturing cost is reduced.

In addition, it is an object of the present invention to provide a method for measuring the position of a substrate one point of an array test apparatus capable of quickly and accurately determining the position of a defective substrate electrode in the array test apparatus.

Therefore, the array test apparatus according to the embodiment of the present invention includes a test unit, a test module, and a position display member. The test unit supports at least a test area of the substrate. The test module includes at least one modulator heads disposed to be transportable on the test unit to identify a defective position of an electrode formed on the substrate. The modulator head includes a camera assembly in which a reference camera and at least one adjacent camera are arranged. The position display member is disposed adjacent to the modulator on the modulator head and the transfer path outside the test unit, and a reference position mark corresponding to the reference camera and a corresponding position mark corresponding to each of the adjacent cameras are formed.

In another aspect of the present invention, a method for measuring a position of a substrate point of a substrate, which may be applied to an array test apparatus having the above structure, is a method of measuring a position of a point of a substrate through the camera assembly, Obtaining a position coordinate based on a reference pixel of the reference camera, obtaining a position coordinate value of the reference pixel of the reference camera based on a preset reference point of the substrate, and based on a preset reference point of the substrate And adding a position coordinate value of a pixel obtained by photographing a point of the substrate with respect to the reference pixel to a position coordinate value of the reference pixel of the reference camera.

According to the present invention, by simultaneously photographing a plurality of cameras on a substrate, the area to be photographed at once can be widened, and at the same time, the driving voltage for driving the respective cameras is reduced, and the camera cost is reduced.

In addition, if only the position coordinates of the reference pixel of the reference camera are taught based on the specific reference point of the substrate, the position coordinates of each pixel of the adjacent camera can be obtained, thereby reducing the measurement time of the specific position.

In addition, since it is not necessary to separately teach a specific pixel of an adjacent camera based on a specific reference point of the substrate, an error according to the teaching is reduced, so that a specific position can be accurately obtained.

1 is a perspective view schematically showing an example of an array test apparatus according to a preferred embodiment of the present invention. In this case, the array test apparatus 10 is equipment for testing electrical defects of the substrate electrodes formed on the substrate 2.

The substrate 2 may be one panel provided in a flat panel display panel. For example, the substrate 2 may be a TFT panel in which a TFT is formed in a TFT LCD substrate.

The array test apparatus 10 may include a test module 50, a test unit 30, and a position display member 200. In addition, the test apparatus 10 may further include a loading unit 20 and an unloading unit 40.

The loading unit 20 may include at least two or more loading plates 22. The loading plates 22 are arranged side by side with a clearance to each other to support the substrate to be tested. The substrate 2 may be supported by the substrate chuck 70 and transferred to the test unit 30.

The test unit 30 is disposed on one side of the loading unit 20, in which an electrical defect of the panel transferred along the loading plate 22 is tested. The test unit 30 may include a test stage 32 on which the substrate is mounted, and a voltage applying unit 38 for applying a voltage to the substrate.

The test module 50 is disposed above or below the test unit 30, or above and below the test unit 30, and detects an error of the substrate electrode disposed on the test stage 32.

The test module 50 has at least one modulator head 100.

The modulator head 100 is disposed to be horizontally movable in at least one axis direction, and includes a fixing block 110, a camera assembly 120, and a modulator block 130.

The fixing block 110 is coupled to be horizontally movable along the guide of the gantry 60 disposed in the direction crossing the test unit 30.

The camera assembly 120 includes a plurality of cameras consisting of a basic camera 121 and at least one adjacent camera 123. The camera assembly 120 may be arranged in a rectangular, square, or the like as a whole. In the array test operation, the cameras included in the camera assembly simultaneously photograph the substrate 2. Therefore, the section photographed at one time becomes wider in proportion to the number of cameras, thereby reducing the test time. In addition, since the size of each camera is not large, the driving power for driving it does not need to be large.

The modulator block 130 is detachably coupled to the fixed block 110. Although not shown in the figure, the modulator block 130 includes a modulator electrode portion and a characteristic change portion. The modulator electrode portion forms a magnetic field between the electrodes of the substrate. The modulator electrode part may be made of a material such as indium tin oxide (ITO) or carbon nano tube (CNT), and generally functions as a common electrode.

The characteristic change unit changes a characteristic that can be seen from the outside according to the intensity of the electric field between the modulator electrode unit and the substrate electrode. The property change unit may be a polymer dispersed liquid crystal (PDLC) film. The PDLC film is disposed between the modulator electrode part and the electrode of the substrate and polarized so that the amount of incident light passing therethrough is changed according to the magnitude of the electric field formed between the modulator electrode part and the substrate electrode.

In this case, the modulator block 130 may further include a translucent substrate. The light transmissive substrate 121 may be formed of a material having a predetermined or more rigidity through light, and may have a modulator electrode portion and a characteristic change portion sequentially coupled to one side thereof.

The position display member 200 is disposed adjacent to the modulator head 100 on the modulator head and the transfer path outside the test unit 30, and includes a reference position mark 221 corresponding to the reference camera and the adjacent position. Corresponding location marks 223 corresponding to each camera are formed. The position display member 200 is preferably disposed adjacent to the test unit 30.

FIG. 1 illustrates that the position display member 200 is located at one side and the other side of the test unit 30, and the modulator heads 100 close to the test unit 30 move to both sides to photograph each of the position display members. The present invention is not limited thereto and may be disposed on one side of the test unit 30, or may be disposed on at least one of the test front and the rear.

In addition, although not shown in the drawings, a backlight may be disposed below the test unit 30. The backlight shines light toward the test unit, and the backlight may be installed to be transportable corresponding to the modulator block 130. In this case, the position display member 200 may be disposed on one side of the backlight.

Through the position display member 200, pixel position coordinates of each of the adjacent cameras 123 are obtained based on a reference pixel of the reference camera 121 before the actual array test operation. That is, the pixel position coordinates of each of the adjacent cameras 123 may be obtained based on only one reference pixel of the reference camera, not based on the reference pixels of the adjacent cameras 123.

Subsequently, if only the position coordinates between the reference pixels of the reference camera 121 are taught from the reference point of the substrate, the actual position coordinates of the pixels photographing the defective substrate electrodes can be obtained based on the reference points of the substrate.

FIG. 2 is an enlarged view of a portion of the position display member 200 in FIG. 1. As illustrated in FIG. 2, the position display member 200 captures a reference position mark 221 captured in a field of view (F121) of the reference camera and an FOV (F123) of each of the adjacent cameras. Corresponding location marks 223 are formed at regular intervals G1 and G2.

In addition, the position display member 200 is captured in the FOV (F121) of the reference camera and the FOV (F123) of each adjacent camera, respectively, and the respective position marks 221, 223 and a predetermined interval ( A plurality of length marks 225 spaced apart with k) may be formed. The function of the reference position mark 221, the corresponding position mark 223, and the length mark 225 will be described later in detail.

The position display member 200 may be disposed to be rotatable about one rotation shaft. That is, the position display member 200 is arranged to be foldable at the outside of the test unit 30, when the image is captured by the cameras are disposed in the optical path of the camera, otherwise folded to the entire array test The size of the device can be reduced.

The unloading unit 40 is disposed on one side of the test unit 30, and the tested substrate 2 is transferred to the excitation unit from the test unit 30 and moved to the outside. In this case, the unloading unit 40 may include an unloading plate 42 which allows the tested panel to be seated thereon or floated at a predetermined interval.

In this case, air holes 24 and 44 for supplying pressure to the loading plate 22 of the loading unit 20 and the unloading plate 42 of the unloading unit 40 to support the substrate are provided. In addition, the loading unit 20 and the unloading unit 40 may include an adsorption plate 70 for adsorbing the substrates.

However, the array test apparatus 10 that may be applied to the present invention is not limited to FIG. 1. The substrate is fixed to the fixed support plate, the test module 50 may be moved to the X, Y axis to test the error of the substrate electrode, the test module 50 is fixed in the horizontal direction, the substrate 2 is X In addition, the substrate electrode may be tested for errors of the substrate electrode while moving along the Y axis.

Each step of the method for measuring the position of a substrate point that can be used in an array test apparatus having the above structure is as follows. First, a position coordinate of each pixel on the adjacent camera 123 is obtained based on the reference pixel P1 of the reference camera 121, and then the reference pixel P1 of the reference camera based on a preset reference point of the substrate. The position coordinate of the specific position can be obtained from the reference point of the substrate by adding the position coordinate value of) and the position coordinate value of the pixel obtained by imaging one point of the substrate on the basis of the reference pixel.

According to the present invention, the position coordinates of each pixel located on the plurality of cameras of one camera assembly are determined based on the reference pixel of one camera (reference camera). This results in the cameras making up the camera assemblies as a whole having a single FOV, resulting in the same effect as a single camera with this sized FOV.

In addition, if the reference pixel of the reference camera included in the modulator head knows only the position coordinate values spaced apart from the reference point of the substrate, the position of the pixels of each camera constituting the camera assembly can be known from the reference point of the substrate. There is no need to separately set the position away from the substrate reference point.

3 to 8 are diagrams showing each step of the method for measuring the position of the substrate one point of the array test apparatus according to an embodiment of the present invention. In this case, for convenience of description, the description will be made based on a single separation camera spaced apart from the first axis (the X axis in the drawing) of the reference camera. However, the present invention may have a plurality of separation cameras in a first axis direction and / or It is also applicable to having a plurality of spaced apart cameras in the biaxial direction.

As shown in FIG. 3, the reference position mark 221 captured in the FOV F121 of the reference camera is the reference camera 121 (see FIG. 1), and the corresponding position mark captured in the FOV F123 of the adjacent camera. 223 is photographed by the adjacent camera 123 (see FIG. 1). Accordingly, the reference position mark 221 is picked up by the reference position mark imaging pixel P121 of the reference camera, and the corresponding position mark 223 is picked up by the corresponding position mark imaging pixel P123 of the adjacent camera. In this case, an actual separation distance G1 may already be defined between the reference position mark 221 and the corresponding position mark 223.

Thereafter, as shown in FIGS. 4 to 6, a position coordinate of each pixel on the adjacent camera is obtained based on the reference pixel of the reference camera.

For this purpose, first, as shown in FIG. 4, a reference which is a distance in a first axis direction between the reference position mark imaging pixel P121 and the corresponding position mark imaging pixel P123 when the FOVs of the cameras are correctly engaged. After the separation distance L is obtained, a difference between the reference separation distance L and the actual separation distance G1 is obtained, as shown in FIG. 5.

That is, as shown in FIG. 4, the first distance L1 from the reference position mark imaging pixel P121 of the first camera to the last pixel Pr1 in the forward direction of the first axis is obtained, and the second camera is obtained. The second distance L2 from the corresponding position mark image pick-up pixel P123 to the last pixel Pr2 opposite the first axis is obtained. Thereafter, the reference distance L may be obtained by adding the first distance L1 and the second distance L2.

Thereafter, as shown in FIG. 5, the first offset value Os1 in the first axis direction is obtained by obtaining a difference between the reference separation distance G1 and the actual separation distance L. Accordingly, it is possible to determine whether the FOV of the adjacent camera and the FOV of the reference camera are engaged, spaced, or overlapped, and the amount of spaced and overlapped.

On the other hand, the separation camera may be shifted from the reference camera to the second axis (Y-axis in the figure). Accordingly, as shown in FIG. 6, a second offset value Os2, which is a second axis shift amount of the separation camera, may be obtained from the reference camera.

To this end, obtaining a third distance L3 which is a distance from the reference position mark imaging pixel P121 to one pixel Pr3 in the second axis direction of the reference camera, and the corresponding position mark imaging pixel. Obtaining a fourth distance L4, which is a distance from P123 to one pixel Pr4 in the second axis direction of the adjacent camera, and obtaining a difference L3-L4 between the third distance and the fourth distance. Thus, the second offset value Os2 can be obtained.

By going through the above steps, a position coordinate value in each pixel of the adjacent camera can be obtained based on the reference pixel of the reference camera.

That is, as shown in FIG. 7, if the distance Pr5 from the reference pixel P1 to the end pixel P2 of the first axis and the specific pixel position value in the adjacent camera are (a1, b1), The specific pixel position value of the adjacent camera becomes (Pr5 + a1-Os1, b1-Os2) based on the reference pixel of the reference camera.

For example, it is assumed that the first offset value Os1 is 10 and the second offset value Os2 is −2 due to some overlap between the FOV F121 of the reference camera and the adjacent camera FOV F123. In addition, it is assumed that the distance Pr5 from the reference pixel P1 to the end pixel of the first axis is 200.

Then, if the specific pixel position value of the adjacent camera is (50, 50), the specific pixel position value of the adjacent camera is (200 + 50-10, 50 + 2) based on the reference pixel of the reference camera. 52).

The position coordinate value may be a coordinate value obtained by converting the pixel value into an actual distance value. In this case, it is easy to know the actual distance of the pixel by multiplying the unit pixel distance by the position coordinate value of the pixel.

There are various methods of obtaining the actual distance of one pixel of the reference camera and one pixel of the adjacent camera. For example, if one camera is photographed while moving at a constant speed in one unit of time, the moving distance can be known, and if the moving distance is divided by the number of pixels captured, the actual unit pixel is simply You can see the distance.

On the contrary, as shown in FIG. 2, at least one length mark 225 formed side by side with a predetermined interval on each of the position marks 221 and 223 corresponds to each of the cameras. And dividing the distance between the position marks 221, 223 and the length mark 225 corresponding to each of the cameras by the number of pixels between the pixel on which the position mark is imaged and the pixel on which the length mark is imaged. The actual distance of each pixel from the adjacent camera and the reference camera can be obtained.

After that, as shown in FIG. 8, the position coordinate values a and b of the reference pixel P1 of the reference camera with respect to the preset reference point P0 of the substrate 2, and the reference pixel The positional coordinate values c and d of the pixel Px obtained by photographing one point of the substrate are added as a reference. Accordingly, it is possible to know simply and accurately at which position of the substrate a defect has occurred.

Since the position coordinates of each pixel of the adjacent camera are already set based on the reference pixel of the reference camera, the test modulator block only needs to teach the position coordinates a and b spaced apart from the reference point of the substrate in this step. .

According to the present invention, even if a plurality of adjacent cameras are arranged, if only the reference pixels of the reference camera are actually taught, the position coordinates of each pixel of all the adjacent cameras can be obtained. Accordingly, since the adjacent cameras are not taught separately during the actual array test operation, an error caused by the teaching process can be prevented and the test time can be shortened.

On the other hand, the position coordinates can be measured by the above method even in the case of the second adjacent camera which is not adjacent to the reference camera but is adjacent to the first adjacent camera directly adjacent to the reference camera.

That is, as shown in FIG. 9, first, a position coordinate value of the position mark imaging pixel P123_a in the FOV F123_a of the first adjacent camera is obtained. Thereafter, the position coordinate value of each pixel on the FOV F123_b of the second adjacent camera is obtained based on the reference pixel P1 of the reference camera.

To this end, offset values Os3 and Os4 of the corresponding position marks 223b of the second neighboring camera are obtained based on the corresponding position marks 223a of the first neighboring camera. The method for obtaining the offset values Os3 and Os4 may include obtaining offset values Os1 and Os2 of the corresponding position marks of the first adjacent camera based on the reference position mark imaging pixel P121 of the reference camera. May be the same. For example, the actual separation distance G2 and the reference separation between the imaging pixel P123_a of the corresponding position mark 223a of the first adjacent camera and the imaging pixel P123_b of the corresponding position mark 223b of the second adjacent camera. By calculating the difference between the distances L5 + L6, the offset value in the second axis direction can be known.

Accordingly, the offset value of the first neighboring camera of the second neighboring camera obtained by adding the offset value of the first neighboring camera to the reference camera can be obtained. have.

So far I looked at the center of the preferred embodiment of the present invention. Those skilled in the art will appreciate that the present invention can be implemented in a modified form without departing from the essential features of the present invention. Therefore, the disclosed embodiments should be considered in descriptive sense only and not for purposes of limitation. The scope of the present invention is shown in the claims rather than the foregoing description, and all differences within the scope will be construed as being included in the present invention.

1 is a perspective view schematically showing an array test apparatus according to a preferred embodiment of the present invention.

FIG. 2 is an enlarged perspective view of the position display member of the camera assembly of FIG. 1.

3 to 8 are conceptual diagrams illustrating each step of a method of measuring a specific position coordinate captured by a camera assembly, and FIG. 3 shows an actual separation distance between a basic camera reference position image picked-up pixel and a corresponding position mark image picked-up pixel of an adjacent camera. A diagram illustrating the steps.

4 is a diagram illustrating a step of obtaining a reference separation distance between a reference position image picked-up pixel and a corresponding position mark image picked-up pixel.

FIG. 5 is a diagram illustrating a step of obtaining a first offset value by obtaining a difference between a reference separation distance and an actual separation distance.

FIG. 6 is a diagram illustrating a step of obtaining a second offset value between a reference camera and a separation camera.

FIG. 7 is a diagram illustrating a step of obtaining a position coordinate value of a specific position pixel of a spaced camera based on a reference pixel of a reference camera.

FIG. 8 is a diagram illustrating a step of obtaining a position coordinate value of a specific position pixel of a spaced camera based on a reference point of a substrate.

9 is a diagram illustrating a step of obtaining an offset value when there are a plurality of adjacent cameras.

 <Brief Description of Drawings>

2: substrate 10: array test apparatus

20: loading unit 30: test unit

40: unloading unit 50: test module

100: modulator head 110: fixed block

120: camera assembly 121: main camera

123: adjacent camera 130: modulator block for coordinate measurement

200: position display member 221: reference position mark

223: corresponding position mark 225: length mark

F121: FOV of reference camera F123: FOV of adjacent camera

k: gap between the length mark and the position mark

P1: reference pixel of the reference camera P0: reference point of the substrate

P121: Reference position mark imaging pixel P123: Correspondence position mark imaging pixel

Os1: first offset value Os2: second offset value

Claims (11)

A test unit supporting a substrate to be tested; A test module disposed at least horizontally and having at least one modulator head detecting a defective position of a substrate disposed in the test unit; And And a position display member disposed adjacent to the modulator head on a movement path of the modulator head in a horizontal outer periphery of the test unit, and having a reference position mark and at least one corresponding position mark. The modulator head includes a camera assembly including a reference camera and at least one adjacent camera, wherein the reference position mark of the position display member is picked up by the reference camera, and the corresponding position mark is picked up by the adjacent camera. Array test apparatus, characterized in that. The method of claim 1, And at least one length mark formed side by side at a predetermined interval on each of the position marks in correspondence with the respective cameras. The method of claim 1, Obtaining the difference between the actual separation distance between the reference position mark and the corresponding position mark and the reference separation distance between the reference position mark imaging pixel and the corresponding position mark imaging pixel when the FOV of the cameras is correctly engaged, And a controller configured to obtain a position coordinate value of each pixel of the pixel based on the reference pixel of the reference pixel. The method of claim 1, And the position display member is arranged to be rotatable along one rotation axis. In the array test apparatus having the structure of claim 1, the method for measuring the position of one point of the substrate through the camera assembly, Obtaining positional coordinates of each pixel on the adjacent camera with reference to the reference pixel of the reference camera; Obtaining a position coordinate value of a reference pixel of the reference camera based on a preset reference point of the substrate; Adding a position coordinate value of a pixel obtained by photographing a point of the substrate relative to the reference pixel to a position coordinate value of the reference pixel of the reference camera based on a preset reference point of the substrate; Substrate one point position measurement method of an array test apparatus comprising a. The method of claim 5, Obtaining the position coordinates of each pixel on the adjacent camera spaced apart from the reference camera in the first axis forward direction: An actual separation distance in the first axis direction between the reference position mark and the corresponding position mark and a distance in the first axis direction between the reference position mark imaging pixel and the corresponding position mark imaging pixel when the FOVs of the cameras are correctly engaged. Obtaining an offset value between the reference position mark and the corresponding position mark, including a first offset value that is a difference between reference distances; And Obtaining a position coordinate value of each pixel of the adjacent camera based on the reference pixel of the reference camera using the offset value; Substrate one point position measurement method of an array test apparatus comprising a. The method of claim 6, Obtaining the reference separation distance; Obtaining a first distance of said reference camera from said reference positionmark picked-up pixel to the last pixel in the first axis forward direction; Calculating a second distance of the neighboring camera from the corresponding positionmark picked-up pixel to the last pixel opposite the first axis; Adding the first and second distances; Position measuring method of the substrate one point of the array test apparatus comprising a. The method of claim 7, wherein The obtaining of the first distance is performed by multiplying the distance per unit pixel of the reference camera by the number of pixels from the reference position-marked imaging pixel to the last pixel on the first axis forward side, The calculating of the second distance is performed by multiplying the distance per unit pixel of the adjacent camera by the number of pixels from the corresponding position-marked imaging pixel to the last pixel on the reverse side of the first axis. Way. The method of claim 6, The calculating of the offset value may further include obtaining a second offset value that is an offset value in a second axis direction perpendicular to the first axis of the adjacent camera. Obtaining the second offset value includes: Obtaining a third distance, from the corresponding mark imaging pixel, to a first pixel in the second axis direction of the adjacent camera; Obtaining a fourth distance from the reference mark image pick-up pixel, the fourth distance being a distance from one reference pixel in a second axis direction of the reference camera;  And obtaining a difference between the third and fourth distances. The method of claim 5, And measuring unit pixel distances of each of the reference camera and the adjacent camera. The method of claim 10, In the position display member, at least one length mark formed side by side with a predetermined interval on each of the position marks is disposed corresponding to each of the cameras, Measuring the unit pixel distance of each of the reference camera and the adjacent camera, the distance between the position mark and the length mark corresponding to each of the camera, the distance between the pixel where the location mark is imaged and the pixel where the length mark is imaged A substrate one point position measuring method of an array test apparatus, characterized by dividing by the number of pixels.

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