KR20020067184A - Method and laser machining apparatus for cutting electrodes of plasma display panel - Google Patents

Abstract

PURPOSE: An electrode isolating method of a plasma display panel and a laser processing apparatus are provided to readily isolate short electrodes using a laser beam. CONSTITUTION: A laser processing apparatus for isolating short electrodes of a plasma display panel comprises a table, a laser, a head(140), a head moving unit, an optical fiber and a vacuum absorbing unit(180). The plasma display panel(100) is loaded on the table. The head(140) is arranged over the table for radiating laser beam generated from the laser on some areas of the short electrodes(103) of the plasma display panel(100) to remove some parts of the electrodes(103) to isolate the electrodes(103). The head moving unit moves the head(140) at least horizontally. The optical fiber is coupled between the laser and the head(140). The vacuum absorbing unit(180) is arranged closely by the table for absorbing fragments generated from the electrodes.

Description

Electrode disconnection method of plasma display panel and laser processing apparatus therefor {Method and laser machining apparatus for cutting electrodes of plasma display panel}

The present invention relates to a method for disconnecting electrodes of a plasma display panel and a laser processing apparatus for the same, and more particularly, to a method for disconnecting shorted electrodes of a plasma display panel from each other and to improve its structure to be suitable for use in the method. It relates to a laser processing apparatus.

Plasma display panels (PDPs), which form images using electrical discharges, have excellent display performance, such as brightness and viewing angle, and their use is increasing day by day. The plasma display panel is classified into a direct current type and an alternating current type according to its discharge type, and may be classified into a counter discharge type and a surface discharge type according to the configuration of the electrodes. The direct current type is a structure in which the electrodes constituting the plasma display panel are exposed to the discharge space, and charges are directly transferred between the corresponding electrodes. The AC type is a structure in which at least one of the corresponding electrodes is surrounded by a dielectric material and forms wall charges without direct transfer of charges between the corresponding electrodes, and uses the wall charges to generate the next discharge. .

As shown in FIG. 1, the plasma display panel 10 is a structure in which a front substrate and a rear substrate are bonded to each other, and a plurality of unit cells selectively emitting light are formed between the front substrate and the rear substrate. have. In addition, a plurality of electrodes 13 for applying a voltage to selectively emit light of unit cells are disposed at four edges of the plasma display panel 10 at predetermined intervals.

The manufacturing process of the plasma display panel 10 includes an aging process for checking whether all the cells of the plasma display panel 10 operate properly for a long time. The aging process is performed by applying a voltage while all of the electrodes 13 of the plasma display panel 10 are shorted in order to easily perform this. At this time, the short of the electrodes 13 is made by printing the aging electrode 15 on the electrodes 13 so as to be orthogonal to them.

After the aging process is completed, the shorted electrodes 13 should be made in a state before shorting, that is, each electrode 13 is disconnected from each other. To this end, a conventional method has been used in which the electrodes 13 are disconnected from each other by removing the aging electrode 15 by an etching process. However, in such an etching process, as it is known, the process is relatively complicated, which requires a lot of process time, and because chemicals are used, there are disadvantages in terms of environment friendliness.

On the other hand, Figure 2 schematically shows the components of a conventional laser processing apparatus. As shown in the drawing, the laser processing apparatus emits a laser beam toward the work piece 1 on the table 30 and the table 30 on which the work piece 1 is mounted on an upper surface thereof. The laser 40 which processes the workpiece | work 1 by a predetermined | prescribed method is provided. In order to enable the laser beam to be irradiated to the entire surface of the workpiece 1 on the table 30, the laser 40 is generally fixed while the table 30 is capable of horizontal and vertical movement.

By the way, in such a conventional laser processing apparatus, when the size of the workpiece 1 is large, for example, when the workpiece 1 is a plasma display panel having a size of about 30 inches to about 60 inches, the whole of the workpiece 1 In order for the surface to be irradiated with a laser beam, the table 30 must be able to move up to twice the horizontal and vertical lengths of the work piece 1, so that the space to be secured for this purpose is unnecessarily large. In order to solve this disadvantage, the table 30 may be fixed and the laser 40 may be moved and processed. In this case, since the laser 40 having a relatively large size must move at a high speed, the laser 40 may be moved. There was a problem that the vibration is easy to occur and it is difficult to precisely position the fine position.

The present invention has been made to solve the above-mentioned problems of the prior art, and is particularly suitable for use in the method and the method which can easily disconnect the shorted electrodes of the plasma display panel using a laser beam. It is an object of the present invention to provide a laser processing apparatus having an improved structure.

1 is a view schematically showing the appearance of a conventional plasma display panel;

2 is a view schematically showing the configuration of a conventional laser processing apparatus;

3A and 3B are views showing a configuration of a laser processing apparatus used in the method of the present invention and a partial perspective view thereof;

4 is a micrograph showing a state of cutting the electrodes of the plasma display panel according to the method of the present invention,

5A to 5C are photographs showing data in various forms, measured using an interferometer, in which electrodes of a plasma display panel are cut according to the method of the present invention.

<Explanation of symbols for the main parts of the drawings>

10,100 ... plasma display panel 13,103 ... electrode

15,105 ... Aging electrode 110 ... Table

121 Support 122 Arm

130 ... laser 131 ... focusing lens

140 ... head 141 ... first lens

142 Second lens 150 Optical fiber

170 ... control unit 180 ... vacuum suction device

SUMMARY OF THE INVENTION In order to achieve the above technical problem, the present invention provides a method for disconnecting electrodes shorted after an aging process of a plasma display panel. A method according to the present invention comprises a portion of each of the electrodes of the plasma display panel. By irradiating a laser beam to each of the electrodes to remove a portion of the electrodes are characterized in that they are disconnected from each other.

Here, the laser beam may be a laser beam having a wavelength of 200 nm to 2,000 nm, preferably an Nd: YAG laser beam having a wavelength of substantially 1,064 nm.

And it provides the laser processing apparatus which performs the above-mentioned method of this invention. A laser processing apparatus according to the present invention comprises: a table on which a plasma display panel is loaded on its upper surface; A laser that emits a laser beam; A head installed above the table and irradiating a portion of each of the electrodes with a laser beam transmitted from the laser to remove a portion of each of the electrodes such that the electrodes of the plasma display panel are disconnected from each other; Head moving means for moving the head in at least the horizontal direction; An optical fiber connected between the laser and the head to transmit a laser beam emitted from the laser to the head; A vacuum suction device installed adjacent to the table to vacuum suction a by-product generated when a portion of each of the electrodes is removed by a laser beam; And a control unit for controlling the laser beam emission of the laser and the movement of the head.

According to the present invention, a process of disconnecting the shorted electrodes of the plasma display panel from each other can be made quickly and environmentally friendly.

Hereinafter, an electrode disconnection method of a plasma display panel according to the present invention and a laser processing apparatus therefor will be described in detail with reference to the accompanying drawings.

3A and 3B show the configuration of a laser processing apparatus used in the method of the present invention.

3A and 3B, a laser processing apparatus for performing the method of the present invention includes a table 110 on which a plasma display panel 100 is loaded. Since the plasma display panel 100 has a relatively large size of 30 inches to 60 inches, in the laser processing apparatus of the present invention, the table 110 is fixedly installed and the head 140 to be described later moves and irradiates a laser beam. Take the way. According to this method, there is an advantage that the installation area of the laser processing apparatus is much narrower.

The laser 130 emitting the laser beam and the laser beam installed on the table 110 and transmitted from the laser 130 are respectively positioned at predetermined positions on the surface of the plasma display panel 100, that is, the electrodes 103. The head 140 is irradiated to a portion of the. Transmission of the laser beam from the laser 130 to the head 140 is via the optical fiber 150. A focusing lens 131 for focusing the laser beam emitted from the laser 130 into the optical fiber 150 is disposed between the laser 130 and one end of the optical fiber 150.

The first lens 141 and the second lens 142 are provided at predetermined intervals inside the head 140. The laser beam transmitted through the optical fiber 150 is made into parallel light by the first lens 141 installed inside the head 140, and is focused again to have an irradiation area of a predetermined size by the second lens 142. do. In this case, the second lens 142 may be a convex lens having a short focal length.

The laser processing apparatus of the present invention supports the head 140 and is provided with head moving means for moving the head 140 in at least the horizontal direction, preferably in the horizontal and vertical directions. As such a head moving means, various methods employed in a conventional general processing apparatus can be employed in the laser processing apparatus of the present invention. As an example, FIG. 3A shows a head moving means having a support 121 and an arm 122. The support 121 is for supporting the arm 122, may support only one end of the arm 122, or may support both ends of the arm 122. The arm 122 is installed to be horizontally moved in the first direction by a predetermined driving means while being supported by the support 121. In this case, the support 121 may be installed to move along the guide rail (not shown) provided to be adjacent to the edge of the table 110 so that the arm 122 may move horizontally together, or the support 121 may be fixedly installed. In addition, only the arm 122 may be horizontally moved along a guide rail (not shown) provided at the upper end of the support 121. Meanwhile, the arm 122 may be installed to vertically move along the vertical direction of the support 121. The head 140 is installed on the arm 122 so as to move horizontally in a second direction (indicated by an arrow in FIG. 3A) orthogonal to the first direction. The heads 140 are horizontally moved in a first direction and a second direction orthogonal to each other by the head moving means having the configuration as described above, and arranged at four edges of the plasma display panel 100. The laser beam can be irradiated to the laser beam.

In addition, a vacuum suction device 180 is provided to be adjacent to the table 110. The vacuum suction device 180 is a by-product, for example, generated when a portion of each of the electrodes 103 is removed by a laser beam. Vacuum suction of product or gas. The vacuum suction device 180 may be installed at the upper and / or lower portion of the table 110, and may also be installed at the side of the table 110. Preferably, the vacuum suction device 180 is installed such that the suction port 181 is directed toward the electrodes 103 disposed at the edge of the plasma display panel 100. In addition, the vacuum suction device 180 may be configured to adjust the position and direction of at least the suction port 181 according to the size of the plasma display panel 100 and the position of the electrodes 103.

In addition, the laser processing apparatus of the present invention is provided with a control unit 170 for controlling the laser beam output of the laser 130 and the movement of the head 140. The control unit 170 controls the beam exit of the laser 130, the intensity of the beam emitted, the moving distance and the moving speed of the head 140, and the like.

As described above, according to the present invention, the laser 130 itself is installed to be moved above the table 110 so that the laser 130 does not directly irradiate a laser beam to the surface of the plasma display panel 100, but rather has a smaller size and a simpler configuration. The head 140 having a structure is installed to be movable to irradiate a laser beam transmitted from the laser 130 through the optical fiber 150. Therefore, the head 140 can be moved quickly and shaking is prevented, thus enabling more precise position control. In addition, the apparatus required for driving can be miniaturized, and driving power can be reduced.

As the laser 130, as described in detail later, it is used to emit an Nd: YAG laser beam having a wavelength of substantially 1,064 nm.

Hereinafter, a method of cutting an electrode of the plasma display panel according to the present invention will be described with reference to FIGS. 3A and 3B. As described above, the plasma display panel 100 undergoes an aging process that checks whether all the unit cells operate properly for a long time, and the aging process includes electrodes disposed at the edges of the plasma display panel 100. This is done by printing the aging electrode 105 on the 103 and applying a voltage while the electrodes 103 are all shorted. After the aging process is completed, the shorted electrodes 103 should be made in a state before shorting, that is, each electrode 103 is disconnected from each other.

To this end, the present invention takes a method of removing a portion of each of the electrodes 103 by irradiating a laser beam to each of the electrodes 103. As a result, since the respective electrodes 103 are cut, the electrodes 103 may be disconnected from each other. At this time, the removed portion of the electrode 103 may be a portion where the aging electrode 105 is printed, it is preferable that the aging electrode 105 is not printed portion. This is because the amount of the electrode removed by the laser beam is reduced, less by-products are generated, the energy required to remove the electrode can be reduced, and the removal time can be shortened.

The method of the present invention as described above may be performed by any device that emits a laser beam, but is performed by the head 140 for irradiating a laser beam transmitted from the laser 130 through the optical fiber 150. It is preferable because it has the advantages as described above. That is, the head 140 moves and irradiates a laser beam to each of the electrodes 103 to remove a portion thereof. The movement of the head 140 and the irradiation position of the laser beam are controlled by the control unit 170 described above.

In addition, a relatively high power laser beam having a wavelength of 200 nm to 2,000 nm may be used as the laser beam. Preferably, an Nd: YAG laser beam having a wavelength of 1,064 nm is used. This relatively short wavelength laser beam has a higher absorption rate in the metallic material than in the longer wavelength laser beam, for example, a CO ₂ laser beam having a wavelength of 10.6 mu m. Therefore, by using a laser beam of a relatively short wavelength as in the present invention, it is possible to remove only the electrode 103 made of a metallic material without damaging the glass substrate. When a high power laser beam having a relatively short wavelength is irradiated to a portion of the electrode 103, the portion is instantaneously evaporated and removed. Thus, the respective electrodes 103 can be cut quickly. On the other hand, when using a CO ₂ laser beam having a relatively long wavelength, there is a problem that a problem that the electrode 103 is melted and stuck to the substrate or the substrate itself is damaged rather than removed.

The intensity of the laser beam to be irradiated may be adjusted by the control unit 170 to the extent that only the electrodes 103 can be cut completely according to the thickness of the electrodes 103 to be cut. The irradiated laser beam is focused by the second lens 142 of the head 140 so that the energy can be concentrated at the cut portion of the electrode 103.

4, 5A and 5B show an experimental result of cutting each of the electrodes of the plasma display panel according to the method of the present invention. 4 is a micrograph, and FIGS. 5A and 5B are photographs showing data in various forms measured using an interferometer. In this experiment, a Nd: YAG laser beam having a wavelength of 1,064 nm transmitted through an optical fiber was used as the laser beam, and the laser beam was set to an output frequency of 30 W and an oscillation frequency of 10 Hz.

First, referring to FIGS. 4 and 5A, it can be seen that the electrodes of the plasma display panel are removed by a predetermined length d, respectively. 5B shows the length length d and thickness h of the removed portion of the electrodes, the length d of which is approximately 200 μm to 260 μm, and the thickness h of about 5 μm to 6 μm to be. In addition, only a portion of the electrode to which the laser beam was irradiated was completely removed and the substrate was shown to be almost intact. After the above experiment, a part of the cut-off test was performed with a mega tester capable of measuring 500 ㏁ and 1,000 V, and a short-circuit test was performed on both sides of the cut electrode.

As described above, according to the method and apparatus of the present invention, since the electrodes are disconnected from each other by removing and cutting a part of each of the electrodes shorted in the aging process of the plasma display panel with a laser beam, In comparison, productivity is improved by shortening the process time, and there is an environment-friendly advantage because no chemicals are used. In addition, since the laser processing apparatus according to the present invention enables precise control and rapid movement of the head, there is an advantage that a relatively large plasma display panel can be processed accurately and at high speed.

Claims (10)

In the method of disconnecting the shorted electrodes after the aging process of the plasma display panel: And removing a portion of each of the electrodes by irradiating a laser beam to a portion of each of the electrodes of the plasma display panel so that the electrodes are disconnected from each other. The method of claim 1, And irradiating the laser beam by a head that moves in a horizontal direction from the top of the plasma display panel and irradiates a laser beam transmitted through the optical fiber from the laser. The method of claim 1, The wavelength of the laser beam is 200nm to 2,000nm electrode disconnection method of the plasma display panel, characterized in that. The method of claim 3, wherein And the laser beam is an Nd: YAG laser beam having a wavelength of substantially 1,064 nm. The method of claim 1, And the laser beam is focused to have a predetermined irradiation area. In the laser processing apparatus for disconnecting the electrodes shorted after the aging process of the plasma display panel: A table on which a plasma display panel is loaded; A laser that emits a laser beam; A head installed above the table and irradiating a portion of each of the electrodes with a laser beam transmitted from the laser to remove a portion of each of the electrodes such that the electrodes of the plasma display panel are disconnected from each other; Head moving means for moving the head in at least the horizontal direction; An optical fiber connected between the laser and the head to transmit a laser beam emitted from the laser to the head; A vacuum suction device installed adjacent to the table to vacuum suction a by-product generated when a portion of each of the electrodes is removed by a laser beam; And And a control unit for controlling the laser beam emission of the laser and the movement of the head. The method of claim 6, And a focusing lens disposed between the laser and one end of the optical fiber to focus a laser beam emitted from the laser into the optical fiber. The method of claim 6, And the head comprises a first lens for converting the laser beam emitted from the optical fiber into parallel light, and a second lens for focusing parallel light of the laser beam passing through the first lens. The method of claim 6, And the laser emits an Nd: YAG laser beam having a wavelength of substantially 1,064 nm. The method of claim 6, The vacuum suction device is installed such that the suction port is directed toward the electrodes disposed at the edge of the plasma display panel, and the position and direction of the suction port can be adjusted according to the size of the plasma display panel and the position of the electrodes. The laser processing apparatus characterized by the above-mentioned.