KR20060088396A - Plasma display panel - Google Patents

Abstract

The present invention relates to a plasma display panel which can improve electromagnetic wave blocking and driving stability by improving a grounding method.

The plasma display panel according to the present invention connects the ground line formed near the inlet to the position where the voltage measurement value is highest on the heat sink.

Description

Plasma Display Panel {PLASMA DISPLAY PANEL}             

1 is a cross-sectional view of a three-electrode surface discharge plasma display panel.

2 is a view schematically showing a conventional plasma display panel.

3 is a view schematically showing a plasma display panel according to the present invention.

4 is a diagram showing a range of positions where voltage measurements are highest.

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

10: upper substrate 12: lower substrate

36, 66: heat sink 32, 62: cabinet

49: back cover 40, 70: scan drive circuit board

42, 72: sustain drive circuit board

41, 71: Power supply board 38, 68: INLET

47, 77: ground wire

The present invention relates to a plasma display panel, and more particularly to a plasma display panel that can improve the grounding performance between boards.

Recently, various flat panel displays have been developed to reduce weight and volume, which are disadvantages of cathode ray tubes. Such flat panel displays include liquid crystal displays, field emission displays, electro luminescence, and plasma display panels (PDPs). .

Referring to FIG. 1, a discharge cell of a three-electrode AC surface discharge type PDP includes a scan electrode 8Y and a sustain electrode 8Z formed on the upper substrate 10, and an address electrode formed on the lower substrate 12. 2) is provided.

Each of the scan electrode 8Y and the sustain electrode 8Z has a line width smaller than that of the transparent electrodes 4Y and 4Z and the transparent electrodes 4Y and 4Z, and is formed on one edge of the transparent electrodes 4Y and 4Z. Bus electrodes 6Y and 6Z. The transparent electrodes 4Y and 4Z are usually formed on the upper substrate 10 using indium tin oxide (ITO) as a material. The metal bus electrodes 6Y and 6Z are formed of a metal such as chromium (Cr) on the transparent electrodes 4Y and 4Z, thereby reducing the voltage drop caused by the transparent electrodes 4Y and 4Z having high resistance. The upper dielectric layer 14 and the passivation layer 18 are stacked on the upper substrate 10 on which the scan electrode 4Y and the sustain electrode 4Z are formed. The upper dielectric layer 14 accumulates wall charges generated during plasma discharge. The protective film 18 protects the upper dielectric layer 14 from sputtering generated during plasma discharge and increases the emission efficiency of secondary electrons. As the protective film 18, magnesium oxide (MgO) is usually used.

The address electrode 2 is formed on the lower substrate 12 in a direction crossing the scan electrode 8Y and the sustain electrode 8Z. The lower dielectric layer 16 and the partition wall 20 are formed on the lower substrate 12 on which the address electrode 2 is formed. The phosphor layer 22 is formed on the surfaces of the lower dielectric layer 16 and the partition wall 20. The partition wall 20 is formed parallel to the address electrode 2 to structurally distinguish the discharge cells, and prevents ultraviolet rays and visible light generated by the discharge from leaking to the adjacent discharge cells. The phosphor layer 22 is excited and emitted by ultraviolet rays generated during plasma discharge to generate visible light of any one of red, green, and blue. An inert mixed gas such as He + Xe, Ne + Xe or He + Ne + Xe for discharging is injected into the discharge space of the discharge cells provided between the upper and lower substrates 10 and 12 and the partition wall 20.

A PDP including such a display panel will be described with reference to the drawings.

2 is a perspective view schematically showing the inside of a general PDP.

Referring to FIG. 2, a typical PDP includes a display panel 34, a heat sink 36, a back cover 49, a cabinet 32, a scan driver circuit board 40, a sustain driver circuit board 42, and A power supply board 41 is provided.

The display panel 34 includes an upper substrate and a lower substrate, not shown, and phosphors are coated on the lower substrate. The upper substrate transmits light generated from the phosphor to display a predetermined image.

The double-sided adhesive tape 30 is attached to a surface of the display panel 34 facing the heat sink 36. The display panel 34 and the heat sink 36 are bonded to each other by the double-sided adhesive tape 30.

The heat dissipation plate 36 is bonded to the display panel 34 by the double-sided adhesive tape 30 to support the display panel 34 and to dissipate heat generated when the display panel 34 is driven. As the material of the heat sink 36, a metallic material having high thermal conductivity, for example, aluminum is used to efficiently dissipate heat generated from the display panel 34.

The scan driver circuit board 40 and the sustain driver circuit board 42 are bonded to the heat sink 36. The scan drive circuit board 40 and the sustain drive circuit board 42 are fastened by screws through holes not shown.

In addition, guards 25 protruding from the heat sink 36 are formed at four corners of the heat sink 36. A hole 15 is formed in the guard 25, and a screw 35 penetrates the hole 15 to fix the heat sink 36 to the back cover 49.

The scan driving circuit board 40 and the sustain driving circuit board 42 supply predetermined driving signals to the electrodes of the display panel 34. To this end, the scan driving circuit board 40 and the sustain driving circuit board 42 have respective driving units, and scan electrodes of the scan driving circuit board 40 and the sustain driving circuit board 42 and the display panel 34. The sustain electrodes are each connected by an FPC (Flexible Printed Circuit), not shown.

The cabinet 32 is installed on the front of the display panel 34 to protect the display panel 12 from external shocks and is composed of a glass and a front filter. The front filter is composed of an optical characteristic film, an electromagnetic shield (EMI) shielding film, and an ultraviolet shielding film. The glass protects the front filter from damage from external impact. The optical characteristic film improves the optical characteristics of the PDP by lowering the luminance of red (R) and green (G) and increasing the luminance of blue (B) among the light incident from the display panel 34. The electromagnetic shielding film shields electromagnetic waves and prevents electromagnetic waves incident from the display panel 34 from being emitted to the outside. The infrared shielding film shields the infrared rays emitted from the display panel 34 to prevent the infrared rays above the reference from being emitted to the outside so that signals transmitted using the infrared rays such as a remote controller can be normally transmitted.

The power supply board 41 supplies power not only to the module but also to other set circuits (VSC, TUNER, etc.) and speakers not shown.

The INLET 28 located at the bottom of the center of the panel is electrically connected to the power supply board 41 to receive the power composed of three phases. In addition, a ground line 47 for grounding the panel is also formed from the INLET and is connected to the ground plate GROUN MARK 44. The ground plate 44 is usually formed around the INLET. The ground wire 47 is connected to the ground plate 44 using a screw.

When the PDP is shipped, the back cover 49 is installed to surround the PDP. The back cover 49 is coupled to the cabinet 32 to protect the plasma display panel from external shocks and to block electromagnetic waves emitted to the rear surface.

In this module, the power supply board 41 and the printed circuit boards 40 and 42 are grounded to the heat sink 36 so that the heat sink 36 also serves as a base voltage source. However, substantially the voltage level of the heat sink 36 is not 0V. This is because the power supply board 41, the scan driving circuit board 40, and the sustain driving circuit board 42 all use a high voltage source to induce voltage on the heat sink 36 formed of a metal plate. Therefore, the heat sink 36 may also be a new EMI source, and an improvement of the connection method between the grounding method and the ground line is required for the EMI improvement side or noise reduction.

Accordingly, it is an object of the present invention to provide a PDP that can reduce EMI emissions and noise by improving the grounding scheme.

In order to achieve the above object, a PDP according to the present invention includes a display panel, a heat sink formed on a rear surface of the display panel, a scan driving circuit board for applying pulses to the scan electrodes, and a sustain drive circuit for applying pulses to the sustain electrodes. A plasma display comprising a substrate, a power supply board for supplying power for driving the display panel, an inlet electrically connected to the power supply board to receive power, and a ground line formed near the inlet. In the panel, the ground line is connected to the position where the voltage measurement value is highest on the heat sink.

The ground wire is connected to the position where the current measurement value is highest on the heat sink.

The ground wire is connected to the heat sink using a PEM nut.

The ground wire is connected to the heat sink using a screw.

The ground line is formed between the scan driving circuit board and the sustain driving circuit board.

Other objects and features of the present invention in addition to the above objects will be apparent from the description of the embodiments with reference to the accompanying drawings.

Hereinafter, the PDP according to the present invention will be described in detail with reference to FIGS. 3 to 4.

The PDP according to the present invention includes a display panel 64, a heat sink 66, a scan driver circuit board 70, a sustain driver circuit board 72, and a power supply board 71.

The display panel 64 includes an upper substrate and a lower substrate, not shown, and phosphors are coated on the lower substrate. The upper substrate transmits light generated from the phosphor to display a predetermined image.

The display panel 64 is formed with a plurality of driving integrated circuits connected to scan electrodes and address electrodes (not shown) for supplying data signals and scan signals, respectively. Driver ICs are formed in the scan drive circuit board 70 and the sustain drive circuit board 72. The double-sided adhesive tape 60 is attached to the surface of the display panel 64 facing the heat sink 66. The display panel 64 and the heat sink 66 are bonded to each other by the double-sided adhesive tape 60.

The heat dissipation plate 66 is bonded to the display panel 64 by the double-sided adhesive tape 60 to support the display panel 64 and to dissipate heat generated when the display panel 64 is driven. As the material of the heat sink 66, a metallic material having high thermal conductivity, for example, aluminum is used to efficiently dissipate heat generated from the display panel 64. The heat dissipation plate 66 and the printed circuit boards 40 and 42 pass through a screw (not shown) formed in the printed circuit board (40) so that the printed circuit boards 40 and 42 are fastened to the heat dissipation plate 66.

In addition, four corners of the heat sink 66 are formed with a guard 45 protruding from the heat sink 66. A hole 55 is formed in the guard 45, and a screw penetrates the hole 45 to fix the heat sink 66 to a back cover (not shown).

The scan driving circuit board 70 and the sustain driving circuit board 72 supply predetermined driving signals to the scan electrodes and the sustain electrodes of the display panel 64. The scan driving circuit board 70 and the sustain driving circuit board 72 are connected to the scan electrode and the sustain electrode of the display panel 64 by a flexible printed circuit (FPC) (not shown).

The cabinet 72 is installed on the front of the display panel 64 to protect the display panel 64 from external shocks and is composed of a glass and a front filter. The front filter is composed of an optical characteristic film, an electromagnetic shield (EMI) shielding film, and an ultraviolet shielding film. The glass protects the front filter from damage from external impact. The optical characteristic film improves the optical characteristics of the PDP by decreasing the luminance of red (R) and green (G) and increasing the luminance of blue (B) among the light incident from the display panel 64. The electromagnetic shielding film shields electromagnetic waves and prevents electromagnetic waves incident from the display panel 64 from being emitted to the outside. The infrared shielding film shields the infrared rays emitted from the display panel 64 to prevent the infrared rays above the reference from being emitted to the outside so that signals transmitted using the infrared rays such as a remote controller can be normally transmitted.

The power supply board 71 supplies power not only to the module but also to other set circuits (VSC, TUNER, etc.) and speakers not shown.

The INLET 68 located at the bottom of the center of the panel is electrically connected to the power supply board 71 to receive a power composed of three phases.

On the other hand, the ground wire is formed from the INLET and is grounded to the heat sink. At this time, the position grounded at the heat sink 66 is grounded at the position where the voltage measurement is highest on the heat sink 66.

This is to prevent the voltage is induced in the heat sink (66). Looking at this, the scan driving circuit board 70 and the sustain driving circuit board 72 are attached to a heat sink 66 which is a metal body. However, as both the scan driving circuit board 70 and the sustain driving circuit board 72 use a high voltage source, a voltage is induced in the heat sink 66 which is a metal body. To this end, the ground wire formed from the INLET 68 is grounded to the heat sink 66, and the position is grounded at the place where the voltage is most induced on the heat sink 66, that is, the voltage measurement value is the highest. The highest voltage on the heat sink 66 can be measured simply by a voltage / current meter (MULTI-META). In general, there is a slight difference depending on the module, but when the position of the highest voltage value is measured using a voltage / current meter, it is formed between the scan driving circuit board 70 and the sustain driving circuit board 72 as shown in FIG. Able to know.

A method of grounding the ground wire 77 to the heat sink 66 may use a PEM nut, or may use a screw. In addition, the ground line 77 may be grounded at positions having high voltage or current measurement values on the heat sink 66 by using a plurality of ground lines instead of one.

In this way, if the ground wire 77 is grounded at the highest voltage or current measurement value on the heat sink 66 without grounding the ground plate near the existing inlet, the voltage or current induced in the heat sink 66 can be suppressed. The voltage level of 66) can be made close to the ideal voltage value of 0V. Accordingly, the heat sink 66 can be prevented from becoming the secondary EMI source, and the signal can be prevented from being distorted due to the ground rather than the voltage value of 0V, thereby enabling more stable driving.

As described above, according to the PDP according to the present invention, the heat sink can be used as a base voltage source of 0V, which enables stable driving.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (6)

A display panel, a heat sink formed on a rear surface of the display panel, a scan driving circuit board for applying pulses to the scan electrodes, a sustain driving circuit board for applying pulses to the sustain electrodes, and a power supply for driving the display panel In the plasma display panel having a power supply board for supplying a power supply, an inlet electrically connected to the power supply board and receiving power, and a ground line formed near the inlet, And wherein the ground line is connected to a position where the voltage measurement is highest on the heat sink. The method of claim 1, And wherein the ground line is connected to a position where the current measurement value is highest in the heat sink. The method of claim 1, And wherein the ground line is connected to the heat sink using a PEM nut. The method of claim 1, And wherein the ground line is connected to the heat sink using a screw. The method of claim 1, And the ground line is formed between the scan driver circuit board and the sustain driver circuit board. The method of claim 1, And a plurality of ground lines, each of which is grounded at a place where the voltage measurement value is high on the heat sink.

Images