KR20080094223A - Plasma display device - Google Patents

Abstract

A plasma display apparatus is provided to block effectively the radiation of electromagnetic waves generated from a panel by attaching an electromagnetic wave shielding layer for preventing the reduction of image quality on a panel. A plasma display apparatus includes a plasma display panel and an electromagnetic wave shielding layer. The electromagnetic wave shielding layer is formed apart from or attached on the plasma display apparatus. The electromagnetic wave shielding layer includes a mesh unit(210) and a ground unit(220). The mesh unit corresponding to a valid area of the plasma display panel is formed by mesh typed conductive material. The ground unit is formed corresponding to an invalid area of the plasma display panel. Color of the mesh unit is darker than that of the ground unit.

Description

Plasma Display Device

1 is a perspective view showing an embodiment of a plasma display panel according to the present invention;

2 illustrates an embodiment of an electrode arrangement of a plasma display panel;

3 is a timing diagram illustrating an embodiment of a method of time-division driving by dividing one frame into a plurality of subfields;

4 to 6 are views showing the embodiments of the electromagnetic shielding film according to the present invention in full view,

7 is a cross-sectional view showing embodiments of the structure of the filter to which the electromagnetic shielding film according to the present invention is applied.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel, and more particularly, to a plasma display device including an electromagnetic shielding film spaced apart or attached to a front surface of the panel.

In general, a plasma display panel is a device for displaying an image including a character or a graphic by applying a predetermined voltage to the electrodes installed in the discharge space to generate a discharge, and the plasma generated during gas discharge excites the phosphor. It is advantageous in that it is easy to enlarge, lighten, and thinner, to provide a wide viewing angle up, down, left and right, and to realize full color and high brightness.

Such a plasma display panel may adversely affect a user and a peripheral device by electromagnetic waves emitted from inside the panel during driving. In order to solve this problem, an electromagnetic shielding film that has been blackened as a whole is used, but there is a problem that the electromagnetic shielding efficiency is lowered due to an increase in the resistance value of the conductive material due to the blackening treatment.

The present invention has been made to improve the above-mentioned problems of the prior art, a plasma having an electromagnetic shielding film that can effectively block the electromagnetic waves emitted from the inside of the panel, and effectively prevent the degradation of the image quality implemented in the panel It is an object to provide a display device.

Plasma display device according to the present invention for solving the above technical problem, the plasma display panel; And an electromagnetic shielding film spaced apart from or adhered to the plasma display panel, wherein the electromagnetic shielding film corresponds to an effective area of the panel, and a mesh part formed of a mesh structure having a conductive material; Corresponding to an invalid area of the panel and having a ground portion, the mesh portion is characterized in that the darker index than the ground portion.

Preferably, the mesh part is blackened, and the sheet resistance of the ground part is preferably 0.0001 (Ω / sq) to 0.005 (Ω / sq).

In addition, it is preferable that the width of the ground portion and the portion formed in the longitudinal direction is different from each other.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. 1 is a perspective view showing an embodiment of a plasma display panel according to the present invention.

As shown in FIG. 1, the plasma display panel includes a scan electrode 11, a sustain electrode 12, a sustain electrode pair formed on the upper substrate 10, and an address electrode 22 formed on the lower substrate 20. It includes.

The sustain electrode pairs 11 and 12 generally include transparent electrodes 11a and 12a and bus electrodes 11b and 12b formed of indium tin oxide (ITO), and the bus electrodes 11b and 12b. 12b) may be formed of a metal such as silver (Ag) or chromium (Cr) or a stack of chromium / copper / chromium (Cr / Cu / Cr) or a stack of chromium / aluminum / chromium (Cr / Al / Cr). . The bus electrodes 11b and 12b are formed on the transparent electrodes 11a and 12a to serve to reduce voltage drop caused by the transparent electrodes 11a and 12a having high resistance.

Meanwhile, according to an exemplary embodiment of the present invention, the sustain electrode pairs 11 and 12 may not only have a structure in which the transparent electrodes 11a and 12a and the bus electrodes 11b 12b are stacked, but also the buses without the transparent electrodes 11a and 12a. Only the electrodes 11b and 12b may be configured. This structure does not use the transparent electrodes (11a, 12a), there is an advantage that can lower the cost of manufacturing the panel. The bus electrodes 11b and 12b used in this structure may be various materials such as photosensitive materials in addition to the materials listed above.

Light between the transparent electrodes 11a and 12a of the scan electrode 11 and the sustain electrode 12 and the bus electrodes 11b and 12b to absorb external light generated outside the upper substrate 10 to reduce reflection. A black matrix (BM, 15) is arranged that functions to block and to improve the purity and contrast of the upper substrate 10.

The black matrix 15 according to the exemplary embodiment of the present invention is formed on the upper substrate 10, the first black matrix 15 and the transparent electrodes 11a and 12a formed at positions overlapping the partition wall 21. And the second black matrices 11c and 12c formed between the bus electrodes 11b and 12b. Here, the first black matrix 15 and the second black matrices 11c and 12c, also referred to as black layers or black electrode layers, may be simultaneously formed and physically connected in the formation process, and may not be simultaneously formed and thus not physically connected. .

In addition, when physically connected to each other, the first black matrix 15 and the second black matrices 11c and 12c may be formed of the same material, but may be formed of different materials when they are physically separated.

The upper dielectric layer 13 and the passivation layer 14 are stacked on the upper substrate 10 having the scan electrode 11 and the sustain electrode 12 side by side. Charged particles generated by the discharge are accumulated in the upper dielectric layer 13, and the protective electrode pairs 11 and 12 may be protected. The protective film 14 protects the upper dielectric layer 13 from sputtering of charged particles generated during gas discharge, and increases emission efficiency of secondary electrons.

In addition, the address electrode 22 is formed in a direction crossing the scan electrode 11 and the sustain electrode 12. In addition, the lower dielectric layer 24 and the partition wall 21 are formed on the lower substrate 20 on which the address electrode 22 is formed.

In addition, the phosphor layer 23 is formed on the surfaces of the lower dielectric layer 24 and the partition wall 21. The partition wall 21 has a vertical partition wall 21a and a horizontal partition wall 21b formed in a closed shape, and physically distinguishes discharge cells, and prevents ultraviolet rays and visible light generated by the discharge from leaking into adjacent discharge cells. have.

Referring to FIG. 1, it is preferable that a filter 100 is formed on a front surface of the plasma display panel according to the present invention, and the filter 100 has an external light blocking sheet, an anti-reflection (AR) sheet, and a near infrared shield (NIR). At least one or more of a sheet, an EMI shielding sheet, a diffusion sheet, and an optical sheet may be included.

The filter 100 may be attached to the front surface of the panel by an adhesive layer made of an adhesive. When the thickness of the adhesive layer is 10 μm to 30 μm, light incident from the outside may be effectively blocked, and the panel 100 may be generated. The emitted light can be effectively emitted to the outside. In addition, in order to protect the panel from external pressure or the like, the thickness of the adhesive layer may be 30 μm to 120 μm.

In addition, the filter 100 may be attached to the panel in the form of a film, the external light blocking sheet, AR (anti-reflection) sheet, NIR (Near Infrared) shield sheet, EMI (Electro Magnetic Interferenc e) shielding on the glass as the base substrate The shape of the glass filter to which the sheet, the diffusion sheet, the optical sheet, or the like is attached may also be possible.

In an embodiment of the present invention, not only the structure of the partition wall 21 illustrated in FIG. 1, but also the structure of the partition wall 21 having various shapes may be possible. For example, a channel in which a channel usable as an exhaust passage is formed in at least one of the differential partition structure, the vertical partition 21a, or the horizontal partition 21b having different heights of the vertical partition 21a and the horizontal partition 21b. A grooved partition structure having a groove formed in at least one of the type partition structure, the vertical partition wall 21a or the horizontal partition wall 21b may be possible.

Here, in the case of the differential partition wall structure, the height of the horizontal partition wall 21b is more preferable, and in the case of the channel partition wall structure or the groove partition wall structure, it is preferable that a channel is formed or the groove is formed in the horizontal partition wall 21b. something to do.

Meanwhile, in one embodiment of the present invention, although the R, G, and B discharge cells are shown and described as being arranged on the same line, it may be arranged in other shapes. For example, a Delta type arrangement in which R, G, and B discharge cells are arranged in a triangular shape may be possible. In addition, the shape of the discharge cell may be not only rectangular, but also various polygonal shapes such as a pentagon and a hexagon.

In addition, the phosphor layer 23 emits light by ultraviolet rays generated during gas discharge to generate visible light of any one of red (R), green (G), and blue (B). Here, an inert mixed gas such as He + Xe, Ne + Xe, and He + Ne + Xe for discharging is injected into the discharge space provided between the upper / lower substrates 10 and 20 and the partition wall 21.

FIG. 2 illustrates an embodiment of an electrode arrangement of a plasma display panel, and a plurality of discharge cells constituting the plasma display panel are preferably arranged in a matrix form as shown in FIG. 2. The plurality of discharge cells are provided at the intersections of the scan electrode lines Y1 to Yn, the sustain electrode lines Z1 to Zn, and the address electrode lines X1 to Xn, respectively. The scan electrode lines Y1 to Yn may be driven sequentially or simultaneously, and the sustain electrode lines Z1 to Zn are driven simultaneously. The address electrode lines X1 to Xn may be driven by being divided into odd-numbered lines and even-numbered lines, or sequentially driven.

Since the electrode arrangement shown in FIG. 2 is only an embodiment of the electrode arrangement of the plasma display panel according to the present invention, the present invention is not limited to the electrode arrangement and driving method of the plasma display panel shown in FIG. 2. For example, a dual scan method in which two scan electrode lines of the scan electrode lines Y1 to Yn are simultaneously scanned may be possible. In addition, the address electrode lines X1 to Xn may be driven by being divided up and down in the center portion of the panel.

FIG. 3 is a timing diagram illustrating an embodiment of a time division driving method by dividing a frame into a plurality of subfields. The unit frame may be divided into a predetermined number, for example, eight subfields SF1, ..., SF8 to realize time division gray scale display. Each subfield SF1, ..., SF8 is divided into a reset section (not shown), an address section A1, ..., A8 and a sustain section S1, ..., S8. Here, according to an embodiment of the present invention, the reset period may be omitted in at least one of the plurality of subfields. For example, the reset period may exist only in the first subfield or may exist only in a subfield about halfway between the first subfield and all the subfields.

In each address period A1,..., A8, an address signal is applied to the address electrode X, and a scan signal corresponding to each scan electrode Y is sequentially applied by one scan electrode line.

In each of the sustain periods S1, ..., S8, a sustain signal is alternately applied to the scan electrode Y and the sustain electrode Z, so that wall charges are formed in the address periods A1, ..., A8. Sustain discharge occurs in the discharge cells.

The luminance of the plasma display panel is proportional to the number of sustain discharge pulses in the sustain discharge periods S1, ..., S8 occupied in the unit frame. When one frame forming one image is represented by eight subfields and 256 gradations, each subfield in turn has a different sustain signal at a ratio of 1, 2, 4, 8 16, 32, 64, and 128. The number of can be assigned. In order to obtain the luminance of 133 gradations, the cells may be addressed and sustained discharged during the subfield 1 section, the subfield 3 section, and the subfield 8 section.

The number of sustain discharges allocated to each subfield may be variably determined according to weights of the subfields according to the APC (Automatic Power Control) step. That is, in FIG. 3, a case in which one frame is divided into eight subfields has been described as an example. However, the present invention is not limited thereto, and the number of subfields forming one frame may be variously modified according to design specifications. Do. For example, the plasma display panel may be driven by dividing one frame into eight or more subfields, such as 12 or 16 subfields.

In addition, the number of sub-tain discharges allocated to each subfield can be variously modified in consideration of gamma characteristics and panel characteristics. For example, the gray level assigned to subfield 4 may be lowered from 8 to 6, and the gray level assigned to subfield 6 may be increased from 32 to 34.

4 to 6 are views showing the embodiments of the electromagnetic shielding film according to the present invention in full view.

4 to 6, the electromagnetic shielding film 200 shields an electromagnetic interference (EMI) on a front surface of a base sheet (not shown) made of a transparent plastic material to prevent EMI emitted from the panel from being emitted to the outside. Perform the function. In this case, the electromagnetic shielding film 200 typically includes a mesh part 200 forming a pattern of a mesh structure using a conductive material having conductivity, and an outer edge of the mesh part 210 for smooth grounding of the electromagnetic shielding film. That is, the grounding part 220 is provided with a grounding part 220 to which the conductive material is applied as a whole so as to correspond to an invalid area of the panel on which an image is not displayed.

Here, the conductive material forming the mesh portion 210 and the ground portion 220 of the electromagnetic wave shielding film 200 is, for example, gold, silver, iron, nickel, chromium, aluminum, copper, etc. to the extent that it can sufficiently block electromagnetic waves. A metal having conductivity may be used, may be formed of a single material, and may be formed of an alloy or multiple layers.

In addition, the mesh unit 210 may be blackened to have a darker color than the ground unit 220, thereby improving contrast of a panel, such as a black matrix formed inside the panel. That is, the image quality of the panel may be degraded due to the intrinsic color of the metal material itself. When external light such as sunlight or electric light is incident on the panel, reflection is suppressed and absorbed from the blackened portion. Therefore, the display image of the PDP can be improved with high contrast. As the blackening treatment method, a plating method is preferable, and in such a case, it is excellent in adhesion and all surfaces of the mesh portion 210 can be easily blackened. As the material of the plating, at least one or two or more compounds selected from copper, cobalt, nickel, zinc, tin, and chromium, and oxide compounds such as copper oxide, copper dioxide, and iron oxide may be used.

At this time, it is preferable that the grounding part 220 is not blackened in order to be connected to the grounding member of the PDP (not shown) to have sufficient conductivity. In other words, it is preferable not to perform blackening in order to have a sufficient sheet resistance value of 0.0001 (Ω / sq) to 0.005 (Ω / sq) for shielding electromagnetic waves.

In addition, as illustrated in FIG. 4, the widths of the portions formed in the horizontal direction and the portions formed in the vertical direction may be different from each other, and as shown in FIG. 220a may be formed, and as shown in FIG. 6, the grounding part 220b may be formed only in the vertical direction, thereby reducing manufacturing costs for forming the electromagnetic shielding film.

7 is a cross-sectional view showing an embodiment of the structure of the filter applied to the electromagnetic wave shielding film according to the present invention, the filter formed on the front surface of the plasma display panel AR / NIR sheet, EMI shielding sheet, external light shielding sheet, optical properties sheet And the like.

Referring to FIG. 7, the AR / NIR sheet 310 has a function of reducing glare by preventing reflection of light incident from the outside on the front surface of the base sheet 313 made of a transparent plastic material. -Reflection layer 311 is attached, and the NIR (Near Infrared) shielding layer 312 is attached to the rear to shield the near infrared rays radiated from the panel so that signals transmitted using infrared rays such as a remote control can be normally transmitted. do.

The base sheet 313 may be applied to various materials in consideration of transparency, insulation, heat resistance, mechanical strength, and the like that can withstand the use conditions and manufacturing. For example, polyester-based resins, polyamide-based resins, polyolefin-based resins, vinyl-based resins, acrylic resins, cellulose-based resins, and the like may be used, and generally have good transparency and a polyethylene having a visible light transmittance of 80% or more. It is preferable to be formed of a polyester-based material such as telephthalate (PET), polyethylene naphthalate, etc., and the thickness of the base sheet 313 is not enough mechanical strength to prevent the sheet from being damaged, and much more than necessary thickness. It may be desirable to form 50 μm to 500 μm in consideration of not spending the cost.

The optical characteristic sheet 320 improves the color temperature and luminance characteristics of light incident from the panel, and the optical characteristic layer 321 formed of a predetermined dye and an adhesive is formed on the front or rear of the base sheet 322 made of a transparent plastic material. do.

The electromagnetic shielding sheet 330 according to the present invention is attached to shield electromagnetic waves emitted from the inside of the panel. In addition, the external light source is most often present at the top of the observer's head indoors or outside. The external light blocking sheet 340 is attached to effectively block the external light so that the black image of the plasma display panel can be darker.

The adhesive 350 is formed between the AR / NIR sheet 310, the optical characteristic sheet 320, the EMI shielding sheet 330, and the external light shielding sheet 340, so that each sheet and the filter 300 are formed. ) To be firmly attached to the front of the panel. In addition, it is preferable that the material of the base sheet included between the sheets is substantially the same material in consideration of the ease of fabrication of the filter 300.

Meanwhile, in FIG. 7, the AR / NIR sheet 310, the optical characteristic sheet 320, the external light blocking sheet 340, and the EMI shielding sheet 330 are stacked in this order, but the external light blocking sheet 340 and the EMI shielding sheet are stacked. The stacking order of 330 may be changed, and the stacking order of each sheet may be differently stacked by those skilled in the art. In addition, at least one layer of the illustrated sheets may be omitted.

In addition, at least one basesheet of the basesheets shown in FIG. 7 may be omitted, and any one of the basesheets is not made of plastic, and hard glass is used to improve the function of protecting the panel. Can be. The glass is preferably formed spaced apart from the panel at a predetermined interval.

Although preferred embodiments of the present invention have been described in detail above, those skilled in the art will appreciate that the present invention may be made without departing from the spirit and scope of the invention as defined in the appended claims. It will be appreciated that various modifications or changes can be made. Accordingly, changes in the future embodiments of the present invention will not depart from the technology of the present invention.

Plasma display device of the present invention configured as described above has an appropriate sheet resistance value, the electromagnetic wave shielding film that can prevent the degradation of the image quality due to the electromagnetic shielding film is attached to the front of the panel, the electromagnetic wave generated inside the panel is emitted to the outside It can effectively block the thing, it is possible to prevent the degradation of the image quality due to the unique color of the mesh portion.

Claims (4)

A plasma display panel; And An electromagnetic shielding film disposed on the plasma display panel to be spaced apart or adhered thereto; The electromagnetic shielding film may include a mesh part corresponding to the effective area of the panel, and the conductive material having a mesh structure; And a ground portion corresponding to an invalid area of the panel, wherein the mesh portion is darker in index than the ground portion. The plasma display apparatus of claim 1, wherein the mesh unit is blackened. The plasma display apparatus of claim 1, wherein the sheet resistance of the ground portion is 0.0001 (Ω / sq) to 0.005 (Ω / sq). The plasma display apparatus of claim 1, wherein the ground portion has a width different from a portion formed in a horizontal direction and a portion formed in a vertical direction.

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