Background Art A flat panel display (FPD) is a display with a flat panel. Flat panel displays may be classified into cathode ray tube (CRT) displays and liquid crystal displays (LCD), which will be described below.

The CRT includes a panel and a funnel attached to the panel. The panel and the funnel are made of glass. In the neck of the funnel is disposed an electron gun. The CRT has high resolution, but is very heavy. On this account, demand and supply of the LCD has recently been increased with the progress of the industry as compared to the CRT. For convenience of description, the flat panel display will hereinafter be referred to as"LCD".

FIG. 1 is a schematic plan view showing a conventional working stage system for flat panel displays, and FIG. 2 is a side view of FIG. 1. As shown in the drawings, the conventional working stage system for flat panel displays comprises a working table 116, on which an LCD 101 to be processed is placed, and a working unit disposed above the working table 116 for carrying out prescribed work on the LCD 101 loaded on the working table 116. At one side of the working table 116 is provided a robot 117 that is movable in one direction to transfer the LCD 101 to the working table 116 or take the LCD 101 off the working table 116.

On the working table 116 are disposed a plurality of supporting pins 119 for supporting the lower surface of the LCD 101. When the LCD 101 is moved to the working table 116 by means of the robot 117, the supporting pins 119 are erected to support the lower surface of the LCD 101 by means of their ends. When the robot 117 is moved away from the working table, the supporting pins 119 are rotated in one direction such that the LCD 101 is placed on the working table 116 while the LCD is in face-to-face contact with the working table.

Above the working table 116 are disposed a pair of columns 118a, which are spaced a prescribed distance from each other. Between the columns 118a is disposed a connecting unit 118b for connecting the columns 118a to each other. The working unit 120 is mounted to the connecting unit 118b such that the working unit moves along the connection unit 118b according to a prescribed electrical signal to carry out prescribed work on the LCD 101.

The prescribed work on the LCD 101 includes a short circuit or disconnection test of an electric signal formable at the LCD 101, repair of the short circuit or the disconnection, and etching. In other words, the prescribed work on the LCD includes all the processes, such as inspection and repair, carried out so that it can be assured that

the LCD 101 is not defective before it is placed on the market, which will be described below.

The operating mechanism of the conventional working stage system for flat panel displays with the above-described construction is as follows: First, an LCD 101 is taken out from a cassette (not shown) containing LCD's to be processed, and is then transferred to the working table 116 by means of the robot 117.

When the LCD 101 is placed above the working table 116 by means of the robot 117, the supporting pins 119 are rotated such that the ends of the supporting pins face upward.

When the supporting pins 119 are erected, the LCD 101 grasped by means of the <BR> <BR> robot 117 is put down on the ends of the supporting pins 119 (i. e. , the LCD is loaded).

After that, the robot 117 returns to its original position.

When the LCD 101 is put down on the ends of the erected supporting pins 119, the supporting pins 119 are rotated in one direction such that the LCD 101 is placed on the working table 116 while the LCD is in face-to-face contact with the working table.

This position of the LCD 101 is a position where prescribed work on the LCD will be carried out.

When the LCD is placed on the prescribed working position by means of the robot 117 and the supporting pins 119 as described above, the working unit 120 is moved along the connecting unit 118b according to a prescribed electric signal so that the prescribed work on the LCD 101 is carried out.

In the conventional working stage system for flat panel displays, the loading of an LCD 101 to be processed, the prescribed work on the LCD 101, and the unloading of the processed LCD 101 are carried out in sequence. The above procedure is applied identically to a great number of LCD's.

In the conventional working stage system for flat panel displays, however, time

required to load the LCD 101 to be processed onto the working table 116 or time required to unload the processed LCD 101 from the working table 116 is much greater than time required to carry out the prescribed work on the LCD 101.

Since it takes a great deal of time to load the LCD 101 to be processed onto the working table and unload the processed LCD 101 from the working table as described above, the prescribed work on the LCD cannot be efficiently carried out. As a result, working efficiency is lowered, and thus productivity is considerably decreased. In fact, the number of LCD's for which a single working table 116 carries out the prescribed work per unit time is not large.

If loading and unloading of an LCD 101 and carrying out prescribed work on the LCD 101 are concurrently carried out on a single working table 116, it is expected that time required to load the LCD 101 to be processed onto the working table 116 or time required to unload the processed LCD 101 from the working table 116 is decreased, and thus the number of LCD's for which a single working table 116 carries out the prescribed work per unit time is increased, whereby working efficiency is increased, and thus productivity is considerably improved.

Disclosure of the Invention Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a working stage system for flat panel displays and a flat panel display working method using the same that is capable of concurrently carrying out loading and unloading of an LCD and carrying out prescribed work on the LCD to decrease loading and unloading time and increase the number of LCD's for which a working table carries out the prescribed work per unit time, thereby

increasing working efficiency and considerably improving productivity.

In accordance with one aspect of the present invention, the above and other objects can be accomplished by the provision of a working stage system for flat panel displays, comprising: a working table having a plurality of working positions sufficient to place at least two flat panel displays to be processed; a working unit disposed above the working table for continuously carrying out prescribed work on the flat panel displays loaded on the respective working positions; a unit-moving device for moving the working unit to or from the working positions; a loading/unloading unit for concurrently carrying out loading of the flat panel displays to be processed onto the vacant working positions and unloading the flat panel displays processed by means of the working unit from the working positions; and a controller for selectively controlling the loading/unloading unit, the working unit, and the unit-moving device.

Preferably, the loading/unloading unit comprises a plurality of supporting pins provided on the respective working positions for supporting the flat panel displays such that the supporting pins support one of the flat panel display when the flat panel display is loaded on the corresponding working position by means of a robot.

The supporting pins may be operated individually by means of the controller.

Preferably, the unit-moving device comprises: an X-axis moving part for moving the working unit in parallel with the loading or unloading direction of the flat panel display onto or from the working table; a Y-axis moving part for moving the working unit in the direction perpendicular to the X-axis moving part; and a Z-axis moving part for partially vertically moving the working unit in the direction perpendicular to an X-Y imaginary plane formed by the X-axis moving part and the Y- axis moving part.

The working unit may be used for a short circuit or disconnection test of an

electric signal formable at the flat panel display, which will be described in connection with a third preferred embodiment of the present invention.

The working unit may used for repair work of bad parts formed at the flat panel display, which will be described in connection with a fourth preferred embodiment of the present invention. Preferably, the repair work includes at least one selected from a group comprising module repair, panel repair, array repair, and depo repair.

The working unit may be used for partial etching of the flat panel display.

Preferably, the working unit is mounted to an A. O. I machine or an A. O. I repairing machine.

In accordance with another aspect of the present invention, there is provided a flat panel display working method using a working stage system for flat panel displays, the method comprising the steps of : loading flat panel displays onto a plurality of working positions provided on a working table; successively moving a working unit to a corresponding working position according to a loading sequence so that the working unit can carry out prescribed work on the flat panel display loaded on the corresponding working position; unloading the flat panel display processed by means of the working unit; and loading a new flat panel display onto the vacant working position, from which the flat panel display is unloaded.

Preferably, the steps are successively carried out by means of a controller.

Brief Description of the Drawings The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a schematic plan view showing a conventional working stage system for flat panel displays; FIG. 2 is a side view of FIG. 1 ; FIG. 3 is a schematic plan view showing a working stage system for flat panel displays according to a first preferred embodiment of the present invention; FIG. 4 is a side view of FIG. 3; FIG. 5 is a schematic plan view showing a working stage system for flat panel displays according to a second preferred embodiment of the present invention; FIG. 6 is a schematic view showing coordinate information of an LCD ; FIG. 7 is a schematic plan view showing a working stage system for flat panel displays according to a third preferred embodiment of the present invention; FIG. 8 is a partially enlarged perspective view of FIG. 7; FIG. 9 is a partially enlarged perspective view of FIG. 8; and FIG. 10 is an enlarged perspective view of the lower region of a working unit.

Best Mode for Carrying Out the Invention Now, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same elements are denoted by the same reference numerals even though they are depicted in different drawings.

First preferred embodiment FIG. 3 is a schematic plan view showing a working stage system for flat panel displays according to a first preferred embodiment of the present invention, and FIG. 4 is a side view of FIG. 3.

As shown in the drawings, the working stage system for flat panel displays according to the first preferred embodiment of the present invention comprises: a working table 16 having different working positions sufficient to place at least two flat panel displays 1 (hereinafter referred to as"LCD") to be processed; a working unit 20 disposed above the working table 16 for continuously carrying out prescribed work on the LCD's 1 loaded on the respective working positions; a loading/unloading unit for concurrently carrying out loading of a new LCD 1 to be processed onto a vacant working position and unloading the LCD 1 processed by means of the working unit 20 from the working position; and a controller 18 for selectively controlling the loading/unloading unit, the working unit 20 and a unit-moving device.

At one side of the working table 16 is provided a robot 17 that is movable in prescribed directions to transfer the LCD 1 to the working table 16 or take the LCD 1 off the working table 16. The robot 17 can be moved by means of an additional moving device 17a as shown in FIG. 3. Of course, it should be understood that a robot used to transfer wafers in the semiconductor industry may be adopted instead of using the robot 17.

In the first preferred embodiment, two working positions are provided on the working table 16. For convenience of description, the two working positions are referred to as a first working position 16a and a second working position 16b, which are arranged side by side from the right side of FIG. 3.

The working unit 20 is moved toward a desired position above the working table 16 by means of a unit-moving device to continuously carry out prescribed work on the corresponding LCD 1.

The prescribed work on the LCD carried out by means of the working unit 20 includes a short circuit or disconnection test of an electric signal formable at the LCD 1

(Refer to a third preferred embodiment), repair of bad parts formed at the LCD l (a repairing machine filed in the name of the applicant), and partial etching of the LCD 1.

In other words, the prescribed work on the LCD includes all the processes carried out before the LCD 1 is placed on the market as a non-defective good.

The unit-moving device comprises various moving parts for moving the working unit 20 along the X, Y, and Z-axes, which will be described in detail in relation to a third preferred embodiment.

The LCD 1 is generally formed in the shape of a thin plate with a relatively large area. Consequently, it is preferable that the robot 17 supports the lower surface of the thin plate-shaped LCD 1, and is then rotated or moved to transfer the LCD 1 to the first or second working position 16a or 16b on the working table 16 or take the LCD 1 off the first or second working position 16a or 16b on the working table 16. The robot 17 is commonly adopted in the semiconductor device industry. Consequently, a further detailed description of the robot will not be given.

When the LCD 1 is placed on the first or second working position 16a or 16b after the LCD 1 is supported by means of the robot 17, the robot 17 cannot be moved away from the working table if there is no gap between the first or second working position 16a or 16b and the robot 17.

In this embodiment, therefore, the working stage system for flat panel displays further comprises a loading/unloading unit, which is operated on the basis of the movement of the robot 17. The loading/unloading unit is provided on the working table 16, as shown in FIGS. 3 and 4. The loading/unloading unit comprises a plurality of supporting pins 19 for supporting the LCD 1. When the LCD 1 is loaded on the first or second working position 16a or 16b by means of the robot 17, the LCD 1 is supported on the corresponding working position by means of the supporting pins 19.

The supporting pins 19 are also controlled by means of the controller 18. In this embodiment, the supporting pins provided on the first working position 16a are referred to as a first supporting pin group 19a, and the supporting pins provided on the second working position 16b are referred to as a second supporting pin group 19b.

When the LCD 1 is transferred to the first or second working position 16a or 16b by means of the robot 17, the first or second supporting pin group 19a or 19b is erected to support the lower surface of the LCD 1 by the ends of the supporting pins of the first or second supporting pin group. When the robot 17 is moved away from the first or second working position, the first or second supporting pin group is rotated in one direction such that the LCD 1 is placed on the corresponding working position of the working table 16 while the LCD is in face-to-face contact with the working table.

As shown in the drawings, all the supporting pins 19 are rotated in one direction.

However, supporting pins (not shown) may be moved vertically by means of an actuator.

Otherwise, compressed air may be injected toward the LCD 1 while the compressed air does not directly contact the LCD 1, and may then be slowly removed so that the LCD 1 can be loaded on the first or second working position 16a or 16b of the working table 16.

The operating mechanism of the working stage system for flat panel displays with the above-described construction according to the first preferred embodiment of the present invention is as follows: First, an LCD 1 is taken out from a cassette containing LCD's to be processed, and is then transferred to the first working position 16a of the working table 16 by means of the robot 17. When the LCD 1 is placed above the first working position 16a of the working table 16 by means of the robot 17, the first supporting pin group 19a is rotated such that the ends of the supporting pins of the first supporting pin group 19a face upward.

When the first supporting pin group 19a is erected, the LCD 1 grasped by means of the robot 17 is put down on the ends of the supporting pins of the first supporting pin group 19a. After the LCD 1 is put down on the ends of the supporting pins of the first erected supporting pin group 19a, the first supporting pin group 19a is rotated in one direction such that the LCD 1 is placed on the first working position 16a of the working table 16 while the LCD is in face-to-face contact with the working table.

When the LCD 1 is placed on the first working position 16a by means of the robot 17 and the first supporting pin group 19a, the working unit 20 is moved by means of the unit-moving device on the basis of an electric signal from the controller 18 so that prescribed work on the LCD 1 is carried out.

Simultaneously when the prescribed work on the LCD placed on the first working position 16a is carried out by means of the working unit 20, the robot 17 is returned to its original position to grasp a new LCD 1 from the cassette. And then, the new LCD is transferred to the vacant working position 16b of the working table 16 by means of the robot 17.

When the LCD 1 is placed above the second working position 16b of the working table 16 by means of the robot 17, the second supporting pin group 19b is rotated such that the ends of the supporting pins of the second supporting pin group 19b face upward. When the second supporting pin group 19b is erected, the LCD1 grasped by means of the robot 17 is put down on the ends of the supporting pins of the second supporting pin group 19b (the LCD is loaded).

After the LCD 1 is put down on the ends of the supporting pins of the second erected supporting pin group 19b, the second supporting pin group 19b is rotated in one direction such that the LCD 1 is placed on the second working position 16b of the working table 16 while the LCD is in face-to-face contact with the working table.

As described above, time required to load the LCD 1 onto the working table or time required to unload the LCD 1 from the working table is much greater than time required to carry out the prescribed work on the LCD 1 by means of the working unit 20.

Consequently, while the new LCD 1 is loaded onto the second working position 16b of the working table 16 by means of the robot 17 and the second supporting pin group 19b, the work on the LCD 1 placed on the first working position 16a, which is carried out by means of the working unit 20, is completed. The working unit successively carries out prescribed work on the LCD placed on the second working position 16b.

The robot 17 is moved to the first working position of the working table 16 to take the processed LCD 1 off the first working position 16a. At this time, the first supporting pin group 19a is erected again according to a signal from the controller 18 to raise the processed LCD 1 above the first working position 16a. Subsequently, the robot 17 supports the lower surface of the LCD 1 raised by means of the first supporting pin group 19a, and then transfers the raised LCD 1 to an additional receiving space.

After that, the robot 17 grasps a new LCD 1 from the cassette containing LCD's 1 to be processed, and then loads the new LCD 1 onto the first working position 16a of the working table 16 in cooperation with the first supporting pin group 19a.

At this time, the prescribed work on the LCD 1 loaded on the second working position 16b has been finished by means of the working unit 20. Consequently, the working unit 20 carries out prescribed work on the LCD 1 loaded on the first working position 16a under the control of the controller 18.

At the same time, the robot 17 is moved to the second working position 16b of the working table 16, and then transfers the LCD 1 processed on the second working position 16b to the receiving space in cooperation with the second supporting pin group

19b. After that, the robot 17 loads a new LCD 1 onto the second working position 16b, which is now vacant.

According to the first preferred embodiment of the present invention as described above, the robot 17, the first and second supporting pin groups 19a and 19b, and the working unit 20 are selectively controlled by means of the controller 18. As a result, the operation of the working unit 20 is not stopped while the LCD 1 is loaded.

Of course, the movement of the robot 17 is not stopped while the working unit 20 is operated.

Consequently, loading and unloading of the LCD 1 and the prescribed work on the LCD 1 are concurrently carried out to decrease loading and unloading time and increase the number of LCD's for which the working table 16 carries out the prescribed work per unit time, thereby increasing working efficiency and considerably improving productivity.

Second preferred embodiment FIG. 5 is a schematic plan view showing a working stage system for flat panel displays according to a second preferred embodiment of the present invention.

In the first preferred embodiment as described above, the first and second working position 16a and 16b are provided on the working table 16 so that loading and unloading of the LCD 1 and the prescribed work on the LCD 1 are concurrently carried out by means of the robot 17, the first and second supporting pin groups 19a and 19b, and the working unit 20.

However, the two working positions 16a and 16b need not be provided on the working table 16.

According to the second preferred embodiment of the present invention, three working positions 16a, 16b, and 16c are provided on the working table 16, as shown in

FIG. 5. The robot 17 is moved by means of the moving device 17a, and the supporting pins 19, the robot 17, and the working unit 20 are controlled by means of the controller 18. Consequently, the second preferred embodiment of the present invention has an advantage in that working efficiency is further improved as compared to the first preferred embodiment of the present invention.

In this case, first to third supporting pin groups 19a to 19c are provided on the three working positions 16a, 16b, and 16c, respectively.

Of course, it is understood that four or more working positions may be provided on the working table 16, the description of which will not be given.

Third preferred embodiment A working stage system for flat panel displays according to a third preferred embodiment of the present invention, which is applied as a testing machine, is shown in FIGS. 6 to 10.

Referring to FIG. 6, prescribed coordinate information, including scanning electrodes and signal electrodes, is provided on the LCD 1. Specifically, contact pad groups 2a to 2d, to which prescribed coordinate information including electric signals is inputted, respectively, are formed on the LCD 1. Each of the contact pad groups 2a to 2d comprises three contact pads. The contact pad groups have different arrangement directions of the contact pads.

Commonly, the contact pad groups 2a to 2d, to which prescribed coordinate information including electric signals is inputted, are formed when the LCD 1 is manufactured by a manufacturing company so that the coordinate information is inputted to the LCD 1. The coordinate information of the LCD 1 supplied from the LCD manufacturing company is tested by a computer manufacturing company to determine where the LCD 1 is defective or not. The non-defective LCD is adopted as a monitor

panel of the computer.

The testing machine for testing the LCD 1 is shown in FIGS. 7 to 10. In this testing machine is adopted the working stage system for flat panel displays according to the present invention.

The LCD testing machine according to the third preferred embodiment of the present invention detects information from the contact pad groups 2a to 2d provided on the LCD 1 as shown in FIG. 6, to which prescribed coordinate information including electric signals is inputted, respectively, to determine whether the LCD is defective or not.

The LCD testing machine comprises: a cabinet 10 forming the external appearance of the machine; a testing stage 12 disposed in the cabinet 10; a working table 16 disposed on the testing stage 12 such that the LCD 1 to be tested is securely located on the working table 16; working units 20 disposed above the working table 16; unit- moving devices for moving the working units in at least one direction; and a monitor 32 for outputting test results carried out by means of probe tips 21a and 22a of the working units 20.

The cabinet 10 includes a plurality of unit panels 1 Oa to protect the testing stage 12 and the working units 20. The cabinet 10 may be closed in the case that the LCD testing machine is not used.

The testing stage 12 is disposed in the cabinet 10, and is formed in the shape of a surface table. In the testing stage 12 is provided a vibration-eliminating device (not shown) for eliminating vibration generated outside and inside the testing stage 12. The testing stage 12 is provided at the four lower corner areas thereof with a plurality of horizontal control members 14 for supporting the testing stage 12. Each of the horizontal control members 14 has a height-adjustment bolt 14a for horizontally

supporting the testing stage 12 and controlling the horizontal position of the testing stage 12.

The working table 16, on which the LCD 1 to be tested is securely loaded, is disposed on the testing stage 12 such that the working table 16 can be shaken at a prescribed angle to the horizontal direction of the upper surface of the working stage 12.

The reason why the working table 16 can be shaken at the prescribed angle to the horizontal direction of the upper surface of the working stage 12 is that the loading position of the LCD to be tested can be reliably and rapidly corrected.

In the case that the loading angle of the robot 17 that loads the LCD 1 can be accurately controlled, it is not necessary to shake the working table 16 at the prescribed angle. A shaking device is not shown in the drawings. For example, the shaking device may be a vibrating element. On the working table 16 are provided the first and second working positions 16a and 16b, as previously described in connection with the previous preferred embodiment of the present invention.

The unit-moving devices are provided at the testing stage 12. The unit-moving devices move the working units 20 in at least one direction so that the probe tips 21 a and 22a of the working units 20 can contact the contact pad groups 2a to 2d (Refer to FIG. 6) formed at the LCD 1 to be tested. Here, the one direction indicates one of the X, Y, and Z-axes, which will be described below.

Each of the unit-moving devices comprises: an X-axis moving part 40 for moving the working unit 20 in parallel with the loading or unloading direction of the LCD 1 onto or from the working table 16; a Y-axis moving part 50 for moving the working unit 20 in the direction perpendicular to the X-axis moving part 40; and a Z-axis moving part 60 provided at the working unit 20 for moving vertically the probe tips 21 a and 22a above the Y-axis moving part 50.

It is difficult that reference numeral of the unit-moving device is indicated on the drawings, and therefore the reference numeral of the unit-moving device will hereinafter be omitted. The movement of the working unit along the X, Y, and Z-axes is accomplished by means of an LM guide structure having ball screws rotated by means of a motor, a detailed description of which will not be given.

The X-axis moving part 40 includes: first and second X-axis supporting members 41a and 41b spaced apart from each other in the direction perpendicular to the loading direction of the LCD, in which the LCD is loaded to one of the first and second working positions 16a and 16b of the working table 16, and disposed such that the first and second X-axis supporting members 41a and 41b can be erected from the upper surface of the testing stage 12; first and second X-axis rail parts 42a and 42b provided at the upper ends of the first and second X-axis supporting members 41a and 41b, respectively; at least one pair of X-axis rail blocks 43 slidably attached to the first and second X-axis rail parts 42a and 42b, each of the X-axis rail blocks 43 being formed in the shape of a dove tail; and an X-axis driving part 44 for sliding the X-axis rail blocks 43 on the first and second X-axis rail parts 42a and 42b.

The X-axis rail blocks 43 may be provided in a pair. In this embodiment, the X- axis rail blocks 43 are provided at four corners about the working table 16 to improve accuracy and reliability of the test while decreasing the testing time.

The Y-axis moving part 50 includes: first and second Y-axis supporting members 5 la and 51b for connecting the corresponding pair of X-axis rail blocks 43 to each other; first and second Y-axis rail parts 52a and 52b provided at the first and second Y-axis supporting members 5 la and 51b, respectively; Y-axis rail blocks 53 each having one end slidably attached to the corresponding first or second Y-axis rail part 52a or 52b and the other end attached to the corresponding working unit 20; and an Y-axis driving part 54 for

sliding the Y-axis rail blocks 53 on the first and second Y-axis rail parts 52a and 52b.

The Y-axis rail blocks 53 are provided at the first and second Y-axis rail parts 52a and 52b in pairs. Consequently, the number of working units 20 attached to the Y- axis rail blocks 53 is four.

The Z-axis moving part 60 includes a stationary unit 62 attached to the corresponding Y-axis rail block 53; a movable unit 64 attached to the stationary unit 62 such that the movable unit 64 can be moved vertically; and a Z-axis driving part 66 for moving vertically the movable unit 64 relative to the stationary unit 62.

To the movable unit 64 of the working unit 20 is mounted a camera 70. The camera 70 is electrically connected to the monitor 32 to transmit an image signal of the LCD 1 to the monitor 32. An operator checks the partial image of the LCD 1 taken by means of the camera 70 to shake the working table 16 at a prescribed angle through a control part (not shown) or to control the position of the working unit 20 through the unit-moving device.

The loading of the LCD 1, the shaking of the working table 16, and the positional control of the working unit 20 by means of the unit-moving device are carried out through the operator's control of the control part 34 while the operator watches the monitor 32. However, it is understood that the above operations may be automatically carried out by means of a prescribed control program.

Between the movable unit 64 and the camera 70 is disposed a camera-moving part 72 for moving the camera in the direction perpendicular to the lifting direction of the movable unit 64. The camera-moving part 72 includes: a horizontal stationary block 72a fixed to the movable unit 64 ; a horizontal movable block 72b attached to the camera 70, engaged with the horizontal stationary block 72a in the shape of a dove tail, and horizontally movable relative to the horizontal stationary block 72a ; and a camera-

driving motor 72c for driving the horizontal movable block 72b. The camera-driving motor 72c is controlled by means of the control part 34.

To the lower part of the working unit 20 are detachably attached first and second probe cards 21 and 22, as shown in FIGS. 9 and 10. The first and second probe cards 21 and 22 have first and second probe tips 21a and 22a contacting the contact pad groups 2a to 2d of the LCD 1 for detecting prescribed information inputted into the contact pad groups 2a to 2d.

As described above, the contact pad groups 2a to 2d of the LCD 1 have different arrangement directions of the contact pads. In response to the different arrangement directions of the contact pad groups 2a to 2d, the first and second probe cards 21 and 22 are disposed at the lower end of the working unit 20 in such a manner that the first and second probe cards 21 and 22 also have different arrangement directions. The first and second probe cards 21 and 22 are supported by means of clamps 21d and 22d, respectively.

Since the first and second probe cards 21 and 22 are disposed such that the first and second probe cards 21 and 22 are perpendicular to each other, the first and second probe tips 21 a and 22a attached to the first and second probe cards 21 and 22 are also disposed such that the first and second probe tips 21a and 22a are perpendicular to each other. Consequently, the first and second probe tips 21a and 22a have different arrangement directions. The ends of the first and second probe tips 21a and 22a are bent so that the first and second probe tips 21 a and 22a can easily contact the contact pad groups 2a to 2d (Refer to FIG. 2).

The first and second probe tips 21a and 22a, which are perpendicular to each other, can be moved vertically on the movable unit 64 independently of each other.

Specifically, the first probe card 21 is moved vertically by means of a first probe lifting

part 21b while the second probe card 22 is moved vertically by means of a second probe lifting part.

Consequently, one of the contact pad groups 2a to 2d is inspected by means of the first probe tip 21a of the first probe card 21, which is movable vertically by means of the first probe lifting part 21b, and another contact pad group is inspected by means of the second probe tip 22a of the second probe card 22, which is movable vertically by means of the second probe lifting part 22b. The inspection results obtained by means of the first and second probe tips 21 a and 22a are outputted to the monitor 32.

The first and second probe lifting parts 21b and 22b adopt lifting cylinders 21c and 22c with LM guides instead of the afore-mentioned motor and ball screw structure.

This is because the lifting cylinders 21c and 22c can be advantageously controlled as compared to the motor control in that each of the first and second probe tips 21 a and 22a is reciprocated between a start position and an end position.

Operation of the LCD testing machine with the above-stated construction will now be described in connection with the working stage system for flat panel displays.

First, an LCD 1 is taken out from a cassette containing LCD's to be processed, and is then transferred to the first working position 16a of the working table 16 by means of the robot 17. When the LCD 1 is placed above the first working position 16a of the working table 16 by means of the robot 17, the first supporting pin group 19a is rotated such that the ends of the supporting pins of the first supporting pin group 19a face upward.

When the first supporting pin group 19a is erected, the LCD 1 grasped by means of the robot 17 is put down on the ends of the supporting pins of the first supporting pin group 19a. After the LCD 1 is put down on the ends of the supporting pins of the first erected supporting pin group 19a, the first supporting pin group 19a is rotated in one

direction such that the LCD 1 is placed on the first working position 16a of the working table 16 while the LCD is in face-to-face contact with the working table.

When the LCD 1 is placed on the first working position 16a by means of the robot 17 and the first supporting pin group 19a, the working units 20 are moved to prescribed positions by means of the unit-moving device on the basis of an electric signal from the controller 18 so that prescribed work on the LCD 1 is carried out.

Specifically, the X-axis rail blocks 43, four in number, are moved along the X- axis on the first and second X-axis rail parts 42a and 42b by means of the X-axis driving part 44. At the same time, the Y-axis rail blocks 53, four in number, are moved along the Y-axis on the first and second Y-axis rail parts 52a and 52b by means of the Y-axis driving part 54.

When the four working units 20 are moved to the contact pad groups 2a to 2d (Refer to FIG. 6) by means of the X-axis moving part 40 and the Y-axis moving part 50, the Z-axis moving part 60 is operated. Specifically, the movable unit 64 is moved relative to the stationary unit 62 by means of the Z-axis driving part 66 such that the movable unit 64 is moved downward by a prescribed distance toward the LCD 1 to be tested.

As the movable unit 64 is moved downward, one of the first and second probe lifting parts 21b and 22b is operated so that one of the first and second probe cards 21 and 22 is moved downward. As a result, the corresponding probe tip contacts the contact pad group. When the probe tip contacts the contact pad group, prescribed information inputted in the contact pad group is detected. The detected value is outputted to the monitor 32 to determine whether the LCD 1 is defective or not.

Simultaneously when the prescribed work on the LCD 1 placed on the first working position 16a is carried out by means of the working units 20, the robot 17 is

returned to its original position to grasp a new LCD 1 from the cassette. And then, the new LCD is transferred to the vacant second working position 16b of the working table 16 by means of the robot 17.

When the LCD 1 is placed above the second working position 16b of the working table 16 by means of the robot 17, the second supporting pin group 19b is rotated such that the ends of the supporting pins of the second supporting pin group 19b face upward. When the second supporting pin group 19b is erected, the LCD 1 grasped by means of the robot 17 is put down on the ends of the supporting pins of the second supporting pin group 19b.

After the LCD 1 is put down on the ends of the supporting pins of the second erected supporting pin group 19b, the second supporting pin group 19b is rotated in one direction such that the LCD 1 is placed on the second working position 16b of the working table 16 while the LCD is in face-to-face contact with the working table.

As described above, time required to load the LCD 1 onto the working table or time required to unload the LCD 1 from the working table is much greater than time required to carry out the prescribed work on the LCD 1 by means of the working units 20.

Consequently, while the new LCD 1 is loaded onto the second working position 16b of the working table 16 by means of the robot 17 and the second supporting pin group 19b, the work on the LCD 1 placed on the first working position 16a, which is carried out by means of the working units 20, is completed. The working units 20 successively carry out prescribed work on the LCD placed on the second working position 16b.

The robot 17 is moved to the first working position 16a of the working table 16 to take the processed LCD 1 off the first working position 16a. At this time, the first

supporting pin group 19a is erected again according to a signal from the controller 18 to raise the processed LCD 1 above the first working position 16a. Subsequently, the robot 17 supports the lower surface of the LCD 1 raised by means of the first supporting pin group 19a, and then transfers the raised LCD 1 to an additional receiving space.

After that, the robot 17 grasps a new LCD 1 from the cassette containing LCD's 1 to be processed, and then loads the new LCD 1 onto the first working position 16a of the working table 16 in cooperation with the first supporting pin group 19a. At this time, the prescribed work on the LCD 1 loaded on the second working position 16b has been finished by means of the working units 20. Consequently, the working units 20 carry out prescribed work on the LCD 1 loaded on the first working position 16a under the control of the controller 18.

At the same time, the robot 17 is moved to the second working position 16b of the working table 16, and then transfers the LCD 1 processed on the second working position 16b to the receiving space in cooperation with the second supporting pin group 19b. After that, the robot 17 loads a new LCD 1 onto the second working position 16b, which is now vacant.

According to the third preferred embodiment of the present invention, loading and unloading of the LCD 1 and the prescribed work on the LCD 1 are concurrently carried out on the single working table 16 to decrease loading and unloading time and increase the number of LCD's for which the working table 16 carries out the prescribed work per unit time, whereby working efficiency is increased, and thus productivity is considerably improved.

Fourth preferred embodiment A fourth preferred embodiment of the present invention, which is not shown in the accompanying drawings, will now be described. Those skilled in the art will sufficiently

understand the fourth preferred embodiment of the present invention since the fourth preferred embodiment of the present invention is applied to a repairing machine filed in the name of the applicant.

According to the third preferred embodiment of the present invention as described above, the working stage system of the present invention is applied to the LCD testing machine. In addition, the present invention is also applied to an LCD repairing machine.

The repairing machine filed in the name of the applicant is very similar in the structure to the system shown in FIG. 7.

When one electrical signal line extending from one of the contact pad groups 2a to 2d shown in FIG. 6 does not run parallel with another adjacent electrical signal line, <BR> <BR> i. e. , one electrical signal line overlaps with another adjacent electrical signal line (it is referred to as"defect"), no correct image is formed on an LCD. Consequently, it is <BR> <BR> necessary to cut off or repair the overlap between the signal lines, i. e. , repair the defect, so that the signal lines do not overlap with each other, which is accomplished by means of the repairing machine.

The repairing machine includes a working table, on which an LCD to be repaired is placed. Above the working table are disposed repairing units (working units) for repairing defect formed at the LCD. The repairing units are moved by means of additional unit-moving devices, respectively. Each repair unit may be a laser scope for photographing the defect formed at the LCD securely placed on the working table and repairing the defect.

A plurality of working positions are provided on the working table of the repairing machine in the same manner as the third preferred embodiment of the present invention. Supporting pins are provided on the corresponding working positions of the

working table, and a robot for transferring the LCD to the working position or taking the LCD from the working position is also provided. The robot, the supporting pins, and the repairing units are controlled by means of an additional controller so that loading and unloading of the LCD and the repairing work on the LCD are concurrently carried out.

Consequently, it is possible to decrease loading and unloading time and to increase the number of LCD's for which the working table carries out the prescribed work per unit time with the result that working efficiency is increased, and thus productivity is considerably improved.

Several embodiments are described above to explain the present invention.

However, the present invention is not limited by the embodiments.

For example, the working unit may carry out other work in addition to the prescribed work carried out in connection with the above-mentioned embodiments. Of course, it is expected that work or machines described below are easily understood by those skilled in the art.

The working unit may carry out repair work, such as module repair, panel repair, and array repair. The operation of the working unit is finished by cutting off defect through the use of a laser. The repair work is carried out per unit panel, unit array, and unit module.

In addition, the working unit may carry out depo repair work. The depo repair work is identical to the above-mentioned other repair work in that defect is cur off through the use of a laser. However, the depo repair work is different from the above- mentioned other repair work in that the cut part can be deposited.

The working unit may be applied to an A. O. I machine or an A. O. I repairing machine. The A. O. I machine is a machine that emits an additional light source to detect the defect, and the A. O. I repairing machine is a repairing machine of the above-

mentioned type with an additional camera for A. O. I inspection.

Industrial Applicability As apparent from the above description, the present invention provides a working stage system for flat panel displays and a flat panel display working method using the same that is capable of concurrently carrying out loading and unloading of an LCD and carrying out prescribed work on the LCD in a single working table to decrease loading and unloading time and increase the number of LCD's for which the working table carries out the prescribed work per unit time, thereby increasing working efficiency and considerably improving productivity.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.