KR20040080565A - Front filter of plasma display panel - Google Patents

Abstract

PURPOSE: A front face filter of a PDP is provided to ground easily an EMI(ElectroMagnetic Interference) shielding film at the front side of the front filter. CONSTITUTION: A front face filter(160) is mounted on the front face of a panel having an effective area of picture and a non-effective area of picture. The front filter includes an electromagnetic interference shielding film(166) and at least one or more optical filter(162). The EMI shielding film shields EMI and prevents EMI from radiating to the outside. The optical filter is formed on the EMI shielding film and is larger than the effective area of picture and smaller than the EMI shielding film.

Description

Front filter of plasma display panel {FRONT FILTER OF PLASMA DISPLAY PANEL}

The present invention relates to a plasma display panel, and more particularly, to a front filter of a plasma display panel capable of providing a grounding structure suitable for a film type front filter.

Plasma Display Panels (hereinafter referred to as "PDPs") are characterized by emitting phosphors by 147 nm ultraviolet rays generated during discharge of an inert mixed gas such as He + Xe, Ne + Xe or He + Ne + Xe. An image containing graphics is displayed. Such a PDP is not only thin and easy to enlarge, but also greatly improved in quality due to recent technology development. In particular, the three-electrode AC surface discharge type PDP has advantages of low voltage driving and long life because wall charges are accumulated on the surface during discharge and protect the electrodes from sputtering caused by the discharge.

1 is a perspective view illustrating a discharge cell structure of a conventional plasma display panel.

Referring to FIG. 1, a discharge cell of a three-electrode AC surface discharge type PDP includes a scan electrode Y and a sustain electrode Z formed on the upper substrate 10, and an address electrode formed on the lower substrate 18. X). Each of the scan electrode Y and the sustain electrode Z has a line width smaller than the line widths of the transparent electrodes 12Y and 12Z and the transparent electrodes 12Y and 12Z and is formed at one edge of the transparent electrode 13Y, 13Z).

The transparent electrodes 12Y and 12Y are usually formed on the upper substrate 10 by indium tin oxide (ITO). The metal bus electrodes 13Y and 13Z are usually formed of metals such as chromium (Cr) and formed on the transparent electrodes 12Y and 12Z to reduce voltage drop caused by the transparent electrodes 12Y and 12Z having high resistance. The upper dielectric layer 14 and the passivation layer 16 are stacked on the upper substrate 10 having the scan electrode Y and the sustain electrode Z side by side. In the upper dielectric layer 14, wall charges generated during plasma discharge are accumulated. The protective layer 16 prevents damage to the upper dielectric layer 14 due to sputtering generated during plasma discharge and increases emission efficiency of secondary electrons. As the protective film 16, magnesium oxide (MgO) is usually used.

The lower dielectric layer 22 and the partition wall 24 are formed on the lower substrate 18 on which the address electrode X is formed, and the phosphor layer 26 is coated on the surfaces of the lower dielectric layer 22 and the partition wall 24. The address electrode X is formed in the direction crossing the scan electrode Y and the sustain electrode Z. The partition wall 24 is formed in a stripe or lattice shape to prevent the ultraviolet rays and the visible light generated by the discharge from leaking to the adjacent discharge cells. The phosphor layer 26 is excited by ultraviolet rays generated during plasma discharge to generate visible light of any one of red, green, and blue. Inert mixed gas is injected into the discharge space provided between the upper and lower substrates 10 and 18 and the partition wall 24.

The PDP is time-divisionally driven by dividing one frame into several subfields having different number of emission times in order to implement grayscale of an image. Each subfield is divided into an initialization period for initializing the full screen, an address period for selecting a scan line and selecting a cell in the selected scan line, and a sustain period for implementing gray levels according to the number of discharges.

For example, when the image is to be displayed with 256 gray levels, as shown in FIG. 2, the frame period (16.67 ms) corresponding to 1/60 second is divided into eight subfields SF1 to SF8. As described above, each of the eight subfields SF1 to SF8 is divided into an initialization period, an address period, and a sustain period. The initialization period and the address period of each subfield are the same for each subfield, while the sustain period is increased at a rate of 2 ⁿ (n = 0,1,2,3,4,5,6,7) in each subfield. .

In the PDP driven as described above, a front filter is installed on the upper substrate 10 to shield electromagnetic interference and prevent reflection of external light.

3 is a cross-sectional view schematically illustrating one side of a conventional plasma display panel.

Referring to FIG. 3, a conventional PDP includes a panel 32 formed by joining an upper substrate 10 and a lower substrate 18, a glass type front filter 30 installed on a front surface of the panel 32, and A heat sink 34 installed at the rear of the panel 32, a printed circuit board 36 installed to be attached to the heat sink 34, a back cover 38 formed to surround the rear of the PDP, and a front filter ( 30 and a support member 42 provided between the front filter 30 and the bag cover 38 to surround the filter support 40. .

The printed circuit board 36 supplies a driving signal to the electrodes of the panel 32. To this end, the printed circuit board 36 includes various driving units not shown. The panel 32 displays a predetermined image in response to a drive signal supplied from the printed circuit board 36. The heat sink 34 dissipates heat generated from the panel 32 and the printed circuit board 36. The back cover 38 protects the panel 32 from external shocks and blocks electromagnetic interference emitted from the rear surface (hereinafter referred to as "EMI").

The filter support 40 supports the rear surface of the front filter 30 so as to be spaced apart from the panel 32 by a predetermined distance. In addition, the filter support 40 electrically connects the EMI shielding film included in the front filter 30 to the back cover 38 grounded to the ground voltage source to discharge the EMI signal from the EMI shielding film. In addition, the filter support 40 prevents EMI from being emitted to the side.

The support member 42 supports the filter support 40, the front filter 30, the bag cover 38, and the like.

The front filter 30 shields EMI and near infrared rays and prevents reflection of external light. To this end, the front filter 30 includes an antireflection film 50, an EMI shielding film 56, and a near infrared (NIR) shielding film 58 as shown in FIG. 4. The glass 52 is further provided between the antireflective film 50 and the EMI shielding film 56, and a black frame 54 is further provided between the glass 52 and the EMI shielding film 56. Here, in practice, an adhesive layer is formed between the films 50, 52, 56, and 58 of the front filter 30 to bond the films 50, 52, 56, and 58. In addition, the structure of the front filter 30 varies slightly depending on the manufacturer. In the present disclosure, the adhesive layer is not illustrated for convenience of description, and the structure of the front filter 30 which is generally used is exemplified.

The antireflection coating 50 prevents light incident from the outside from being reflected back to the outside to improve the contrast of the PDP. The antireflective film 50 is formed on the surface of the front filter 30. In addition, the antireflection film 50 may be further formed on the rear surface of the front filter 30.

The glass 52 prevents the front filter 30 from being damaged from an external impact. In other words, the glass 52 supports the front filter 30 to prevent the front filter 30 from being damaged from an external impact.

The black frame 54 is formed outside the effective screen to sharpen the outline of the screen.

The EMI shielding film 56 prevents EMI emitted from the panel 32 from being discharged to the outside by discharging the EMI. To this end, as shown in FIG. 5, the EMI shielding film 56 is electrically connected to the filter support 40 through the grounding electrodes 55 formed at both sides of the NIR shielding film 58 and the anti-reflective film 50 located on the rear side thereof. Is connected.

The NIR shielding layer 58 shields the NIR emitted from the panel 32 to prevent the NIR above the reference from being emitted to the outside so that signals transmitted using the IR, such as a remote controller, can be normally transmitted. The EMI shielding film 56 and the NIR shielding film 58 may be composed of one layer.

This conventional front filter 30 is used for the glass 54 to prevent the front filter 30 from being damaged by the impact from the outside. However, when the glass 54 is inserted into the front filter 30 in this way, the thickness of the front filter 30 becomes thick. In addition, when the glass 54 is inserted into the front filter 30, the weight becomes heavy and the manufacturing cost increases.

Therefore, the film type front filter 60 from which the glass 54 was removed as shown in FIG. 6 has been proposed. The film front filter 60 includes an antireflection film 62, a black frame 64, an EMI shielding film 66, and a NIR shielding film 68. Here, an adhesive layer is formed between the films 62, 66 and 68 of the film type front filter 60 to bond the films 62, 66 and 68 to each other.

The antireflective film 62 is formed on the surface of the film type front filter 60 to prevent the light incident from the outside from being reflected back to the outside. The antireflection film 62 may be further formed on the rear surface of the film type front filter 60. The black frame 64 is formed outside the effective screen to sharpen the outline of the screen.

The EMI shielding film 66 shields the EMI to prevent the EMI incident from the panel 32 from being emitted to the outside. The NIR shielding film 68 shields the NIR incident from the panel 32. The NIR shielding film 68 prevents the NIR above the reference from being emitted to the outside so that signals transmitted from the remote controller or the like to the panel 32 can be normally transmitted. Meanwhile, the EMI shielding film 66 and the NIR shielding film 68 may be composed of one layer.

Such a film type front filter 60 has an advantage that the film is lighter and thinner than the front filter 30 including the glass 54. In addition, the film type front filter 60 may reduce the manufacturing cost compared to the front filter 30 including the glass 54. However, since the film type front filter 60 is attached to the front surface of the panel 32, the EMI shielding film 66 is formed when the grounding electrode 65 is formed on the back surface of the film type front filter 60 as shown in FIG. A problem arises in that it is difficult to connect the filter to the filter support 40. Accordingly, a grounding structure suitable for the film type front filter 60 is required.

Accordingly, an object of the present invention is to provide a front filter of a plasma display panel capable of providing a grounding structure suitable for a film type front filter.

1 is a perspective view showing a discharge cell structure of a conventional three-electrode AC surface discharge type plasma display panel.

2 is a diagram illustrating a frame for expressing 256 gray levels in a typical plasma display panel.

3 is a cross-sectional view schematically showing one side of a conventional plasma display.

4 is a cross-sectional view schematically showing the glass type front filter shown in FIG. 3.

5 is a view showing in detail the ground structure of the glass front filter and the filter support shown in FIG.

6 is a cross-sectional view schematically showing a conventional film type front filter.

7 illustrates a front filter of a plasma display panel according to a first embodiment of the present invention;

8 is a diagram illustrating a front filter of a plasma display panel according to a second embodiment of the present invention.

FIG. 9 illustrates a plasma display panel equipped with the front filter shown in FIGS. 7 and 8.

10 is a view showing in detail the grounding structure of the front filter and the filter support shown in FIG.

<Description of Symbols for Main Parts of Drawings>

10: upper substrate 12Y, 12Z: transparent electrode

13Y, 13Z: bus electrode 14, 22: dielectric layer

16: protective film 18: lower substrate

24: partition 26: phosphor layer

30,60,70,160,260: Front filter 32,72: Panel

34,74: heat sink 36,76: printed circuit board

38,78 back cover 40,80 filter support

42,82: support member 50,62,162,262: antireflective film

52: glass 54,64,164: black frame

55,65,165,265,365: Grounding electrodes 56,66,166,266: EMI shielding film

58,68,168,268: NIR shields

In order to achieve the above object, the front filter of the plasma display panel according to an embodiment of the present invention is an electromagnetic interference shielding film to shield the electromagnetic interference to prevent the electromagnetic interference incident from the panel is emitted to the outside, and And at least one optical filter film formed on an upper surface of the miraculous interference shielding film and formed larger than the effective screen area and smaller than the electromagnetic interference shielding film.

It is characterized in that it further comprises a grounding electrode formed on the outer portion of the optical filter film to ground the electromagnetic interference shielding film.

An anti-reflective film which prevents the light incident to the outside from being reflected back to the outside, a near-infrared shielding film which prevents the NIR emitted above the reference from being emitted to the outside so as to shield the NIR emitted from the panel and transmit a signal normally, and the effective screen Further characterized in that it further comprises a black frame formed to sharpen the outline.

The optical filter film may include at least one of the anti-reflective film and the near-infrared shielding film.

The black frame is formed on the back of the front filter.

The grounding electrode is formed on an upper portion of the front filter.

The grounding electrode is formed between the side of the optical filter and the top surface of the electromagnetic interference shielding film.

The grounding electrode is formed between a portion of the top surface and the side of the optical filter and the top surface of the electromagnetic interference shielding film.

The grounding electrode is formed in the ineffective screen region.

The grounding electrode may be used as the black frame.

The grounding electrode may be extended to a boundary between the invalid screen area and the effective screen area.

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

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 7 to 10.

7 is a cross-sectional view illustrating a front filter of a plasma display panel according to a first embodiment of the present invention.

Referring to FIG. 7, the film-type front filter 160 of the PDP according to the first embodiment of the present invention includes an anti-reflection film 162, an electrode for grounding 165, an EMI shielding film 166, an NIR shielding film 168, and the like. It has a black frame 164. Here, an adhesive layer is formed between the films 162, 166 and 168 of the film front filter 160 to bond the films 162, 166 and 168.

The antireflective film 162 is formed on the surface of the film type front filter 160 to prevent the light incident from the outside from being reflected back to the outside. At this time, the antireflection film 162 formed on the upper surface of the film type front filter 160 is formed larger than the effective screen of the PDP and smaller than the EMI shielding film 166 to form the grounding electrode 165. The EMI shield 166 is grounded through the top surface of the film type front filter 160 through the ground electrode 165 formed as described above. Therefore, even if the film type front filter 160 is attached to the panel 72, the EMI shielding film 166 can be easily grounded.

The EMI shield 166 shields the EMI to prevent the EMI incident from the panel 72 from being emitted to the outside. To this end, the EMI shielding film 166 discharges the EMI through the grounding electrode 165 formed between the upper side and the antireflective film 162 side. In this case, the grounding electrode 165 is formed on the upper portion of the film type front filter 160. That is, the grounding electrode 165 is formed between the side surface of the antireflection film 162 and the top surface of the EMI shielding film 166. In addition, the grounding electrode 165 is formed between some top surfaces and side surfaces of the anti-reflection film 162 and the top surface of the EMI shielding film 166.

The NIR shielding film 168 shields the NIR incident from the panel 72. The NIR shielding layer 168 prevents the NIR above the reference from being emitted to the outside so that signals transmitted from the remote controller or the like to the panel 72 can be normally transmitted. At this time, when the NIR shielding film 168 is located on the upper surface of the EMI shielding film 166, the NIR shielding film 168, like the antireflection film 162, is larger than the effective screen of the PDP to form the grounding electrode 165, and the EMI shielding film. Smaller than 166. The EMI shielding film 166 and the NIR shielding film 168 may be formed of one layer.

The anti-reflective film 162 may be formed on the surface of the film type front filter 160 and may be further formed on the rear surface of the film type front filter 160 to prevent the light incident from the outside from being reflected back to the outside. At this time, the black frame 164 is formed on the outside of the effective screen and the back surface of the anti-reflective film 162 to sharpen the outline of the screen.

8 is a view showing a film type front filter of a plasma display panel according to a second embodiment of the present invention.

Referring to FIG. 8, the film type front filter 260 includes an antireflection film 262, an electrode for grounding 264, an EMI shielding film 266, and an NIR shielding film 268. Here, an adhesive layer is formed between the films 262, 266 and 268 of the film type front filter 260 to bond the films 262, 266 and 268.

The antireflective film 262 is formed on the surface of the film type front filter 260 to prevent the light incident from the outside from being reflected back to the outside. At this time, the anti-reflection film 262 formed on the surface of the film type front filter 260 is larger than the effective screen of the PDP and smaller than the EMI shielding film 266 to form the grounding electrode 264. The EMI shielding film 266 is grounded to the top surface of the film type front filter 260 through the grounding electrode 264 formed as described above. Therefore, even if the film type front filter 260 is attached to the panel 72, the EMI shielding film 266 can be easily grounded. In addition, the grounding electrode 264 also serves as a black frame formed to sharpen the outline of the screen. For this purpose, the grounding electrode 265 extends to the effective screen boundary. Therefore, since a separate black frame is not necessary, the thickness can be further reduced.

The EMI shielding film 266 shields the EMI to prevent the EMI incident from the panel 72 from being emitted to the outside. To this end, the EMI shielding film 166 discharges EMI through the grounding electrode 265 formed between the upper side and the side surface of the antireflective film 162. At this time, the grounding electrode 265 is formed on the top of the film type front filter 260.

The NIR shielding film 268 shields the NIR incident from the panel 72. The NIR shielding layer 268 prevents the NIR above the reference from being emitted to the outside so that signals transmitted from the remote controller or the like to the panel 72 can be normally transmitted. At this time, when the NIR shielding film 268 is located on the upper surface of the EMI shielding film 266, like the anti-reflective film 262, the NIR shielding film 268 is larger than the effective screen of the PDP to form the grounding electrode 265. Smaller than 266. The EMI shielding film 266 and the NIR shielding film 268 may be formed of one layer.

The antireflective film 262 may be formed on the surface of the film type front filter 260 and may be further formed on the rear surface of the film type front filter 260 to prevent light incident from the outside from being reflected back to the outside.

9 is a cross-sectional view illustrating a plasma display panel equipped with the front filter illustrated in FIGS. 7 and 8.

Referring to FIG. 9, the PDP according to the present invention includes a panel 72 formed by joining an upper substrate and a lower substrate, a film type front filter 70 installed on the front of the panel 72, and a panel 72. A heat sink 74 installed at the rear of the substrate, a printed circuit board 76 installed to be attached to the heat sink 74, a back cover 78 formed to surround the back of the PDP, and a film type front filter 160 And a filter support portion 80 for connecting the bag cover 78 and a support member 82 provided between the film type front filter 160 and the bag cover 78 to surround the filter support portion 80. .

The printed circuit board 76 supplies a driving signal to the electrodes of the panel 72. To this end, the printed circuit board 76 includes various driving units not shown. The panel 72 displays a predetermined image in response to a drive signal supplied from the printed circuit board 76. The heat sink 74 dissipates heat generated from the panel 72 and the printed circuit board 76. The back cover 78 protects the panel 72 from external shocks and blocks EMI emitted to the rear surface.

The filter support portion 80 electrically connects the film type front filter 70 to the bag cover 78. Such a filter support 80 grounds the film type front filter 70 to the bag cover 78 and prevents EMI from being emitted to the side. The support member 82 supports the filter support 80, the film front filter 70, and the back cover 78.

The filter support unit 80 electrically discharges the EMI signal from the EMI shielding film by electrically connecting the EMI shielding film included in the film type front filter 70 to the back cover 78 grounded to the ground voltage source. In addition, the filter support 40 prevents EMI from being emitted to the side.

The film type front filter 70 shields EMI and prevents reflection of external light. At this time, the ground electrode is formed on the film front filter 70 to shield the EMI. In addition, the film type front filter 70 lowers the luminance of red (R) and green (G) and increases the luminance of blue (B) to improve the optical characteristics of the PDP. In addition, the film type front filter 70 shields the NIR to prevent malfunction of the remote control.

On the other hand, the filter support unit 80 grounds the EMI shielding film through the grounding electrode 365 formed on the front side of the film type front filter 70 as shown in FIG. That is, as in the first and second embodiments, the anti-reflective film is formed larger than the effective screen of the PDP and smaller than the EMI shielding film so that the EMI shielding film can be connected to the filter support 80 through the grounding electrode 365. Such a filter support portion 80 electrically connects the EMI shielding film of the film type front filter 70 to the bag cover 78.

As described above, the film type front filter of the plasma display panel according to the present invention forms a ground electrode along the outer edge of at least one optical filter film formed as a front filter upper layer and larger than an effective screen and smaller than an EMI shielding film. Accordingly, the film type front filter of the plasma display panel according to the present invention can easily ground the EMI shielding film on the front side of the front filter.

In addition, the film type front filter of the plasma display panel according to the present invention extends the grounding electrode to the effective screen boundary so as to replace the role of the black frame, so that a separate black frame is not required, and thus the thickness can be further reduced.

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 (11)

In the front filter provided in the front of a panel having an effective screen area and an invalid screen area, An electromagnetic interference shielding film that shields electromagnetic interference and prevents electromagnetic interference incident from the panel from being emitted to the outside; And at least one optical filter layer formed on an upper surface of the electromagnetic interference shielding film and formed larger than the effective screen area and smaller than the electromagnetic interference shielding film. The method of claim 1, And a grounding electrode formed at an outer portion of the optical filter film to ground the electromagnetic interference shielding film. The method of claim 2, An anti-reflective film which prevents light incident to the outside from being reflected back to the outside; A near-infrared shielding film for shielding the NIR radiated from the panel to prevent the NIR from being emitted to the outside so as to normally transmit a signal; The front filter of the plasma display panel further comprises a black frame formed to sharpen the outline of the effective screen. The method of claim 3, wherein And the optical filter film comprises at least one of the anti-reflective film and the near-infrared shielding film. The method of claim 3, wherein The black frame is a front filter of the plasma display panel, characterized in that formed on the back of the front filter. The method of claim 2, And the ground electrode is formed on the front filter. The method of claim 6, And the grounding electrode is formed between a side surface of the optical filter and an upper surface of an electromagnetic interference shielding film. The method of claim 6, And the grounding electrode is formed between a portion of the top surface and the side surface of the optical filter and the top surface of the electromagnetic interference shielding film. The method of claim 2, And the ground electrode is formed in the ineffective screen region. The method of claim 9, And the ground electrode may be used as the black frame. The method of claim 10, And the ground electrode extends to a boundary between the invalid screen area and the effective screen area.