This application claims priority to and the benefit of Korean Patent Application No. 10-2006-0107975, filed on Nov. 2, 2006, in the Korean Intellectual Property Office, the entire content of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to a plasma display panel, and more particularly, to a plasma display panel having an improved black area ratio and bright room contrast.
2. Description of the Related Art
A plasma display panel (PDP) generates plasma by electrical discharge. Ultra violet (UV) rays radiate from the plasma to excite a fluorescent layer. Images are displayed using red, green, and blue light generated in the fluorescent layer.
A plasma display panel can be used for large displays. Since the plasma display panel is an emissive display element, the plasma display panel reproduces color with high quality and provides a wide viewing angle. Therefore, the plasma display panel displays high quality images. In addition, since plasma display panel manufacturing processes are simpler than those of liquid crystal display (LCD) manufacturing, yield of the plasma display panel is high, and costs of the plasma display panel are low.
The PDPs are classified into direct current (DC) and alternating current (AC) types, according to discharge types. The DC type plasma display panel has a structure in which electrodes are exposed to discharge spaces. Charges move directly between corresponding electrodes.
In the AC type plasma display panel, electrodes are covered with a dielectric layer, and discharge is carried out by wall charges. Recently, the AC type plasma display panel has been widely used.
According to the disposition structure of electrodes, the PDPs can be classified into an opposed discharge type and a surface discharge type. In the opposed discharge type plasma display panel, display electrodes are disposed on the front and rear substrates. Discharge is carried out from the front substrate toward the rear substrate. In the surface discharge type plasma display panel, display electrodes are disposed on the same substrate. Discharge is carried out on one surface of the substrate.
In the aforementioned plasma display panel, the discharge cells are selected by using the memory characteristic of the wall charges. Discharges take place in the selected discharge cells. The discharges are suitably combined to display images.
Specifically, in bright room conditions, external light is reflected by the panel, in addition to the light generated in the discharge cells. As a result, a bright room contrast deteriorates. Accordingly, the image display performance of the plasma display panel deteriorates.
Various attempts to improve the aforementioned image display performance of the plasma display panel have been made. Though methods of improving contrast by increasing black area ratio and improving luminance of the panel by increasing emission efficiency have been used, it is desirable to simplify the manufacturing processes and improve the bright room contrast.
An exemplary embodiment according to the present invention provides a plasma display panel of which black area ratio and bright room contrast are improved without additional components.
According to an aspect of an exemplary embodiment of the present invention, there is provided a plasma display panel including: a front substrate; a rear substrate facing the front substrate and spaced apart from the front substrate; a plurality of address electrodes extending in a first direction on the rear substrate; a plurality of barrier ribs between the front substrate and the rear substrate, the barrier ribs defining a plurality of discharge cells; a plurality of display electrodes extending in a second direction crossing the first direction and corresponding to the discharge cells, wherein the display electrodes include bus electrodes colored a third chromatic color; a dielectric layer on the front substrate, the dielectric layer covering the display electrodes and colored a first chromatic color that is in a subtractive color mixture relationship with the third chromatic color; and a filter disposed on an outer surface of the front substrate, the filter including: a plurality of light guides including incident surfaces and emitting surfaces, wherein areas of the incident surfaces are larger than areas of the emitting surfaces; and a plurality of non-glare members that are adjacent to the light guides and colored a second chromatic color.
In the above aspect of an exemplary embodiment of the present invention, the second chromatic color and the third chromatic color may be in a complementary color relationship. In addition, the third chromatic color and the first chromatic color may be in a complementary color relationship. In addition, the second chromatic color may be a shade of blue. The dielectric layer may be colored a shade of blue by adding at least one of manganese (Mn), nickel (Ni), or cobalt (Co) to the dielectric layer. The third chromatic color may be a shade of yellow red. The dielectric layer may be colored a shade of yellow red by adding at least one of copper (Cu), antimony (Sb), or chromium (Cr) to the dielectric layer. The bus electrodes may include a single layer.
According to an aspect of another exemplary embodiment of the present invention, there is provided a plasma display panel including: a front substrate; a rear substrate facing the front substrate and spaced apart from the front substrate; a plurality of address electrodes extending in a first direction on the rear substrate; a plurality of barrier ribs between the front substrate and the rear substrate and defining a plurality of discharge cells; a plurality of display electrodes extending in a second direction crossing the first direction, wherein the display electrodes include bus electrodes colored a third chromatic color; a dielectric layer covering the display electrodes and colored a first chromatic color that is in a subtractive color mixture relationship with the third chromatic color; and a filter on an outer surface of the front substrate, the filter including: a conductive film on the outer surface of the front substrate; and a non-glare layer on the conductive film and colored a second chromatic color.
In the above aspect of an exemplary embodiment of the present invention, the conductive film may include ITO (indium tin oxide) or Copper (Cu), and one side of the conductive film is electrically connected to a ground member. In addition, the second chromatic color and the third chromatic color may be in a complementary color relationship. In addition, the third chromatic color and the first chromatic color may be in a complementary color relationship.
According to an aspect of another exemplary embodiment of the present invention, there is provided a plasma display panel including: a rear substrate; a front substrate facing the rear substrate, the front substrate spaced apart from the rear substrate and colored a second chromatic color; a plurality of address electrodes extending in a first direction on the rear substrate; a plurality of barrier ribs between the front substrate and the rear substrate and defining a plurality of discharge cells; a plurality of display electrodes extending in a second direction crossing the first direction and corresponding to the discharge cells, wherein the display electrodes include bus electrodes colored a third chromatic color; and a dielectric layer covering the display electrodes and colored a first chromatic color in a subtractive color mixture relationship with the third chromatic color.
In the above aspect of an exemplary embodiment of the present invention, the second chromatic color and the third chromatic color may be in a complementary color relationship. In addition, the third chromatic color and the first chromatic color may be in a complementary color relationship.
The above and other features and aspects of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:
The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. There may be parts shown in the drawings, or parts not shown in the drawings, that are not discussed in the specification as they are not essential to a complete understanding of the invention. Like reference numerals designate like elements throughout the specification.
Hereinafter, a plasma display panel according to exemplary embodiments of the present invention will be described in detail.
As shown in
The rear substrate 10 faces the front substrate 15, and the rear and front substrates 10 and 15 are parallel with each other at a distance (that may be predetermined). The address electrodes 11 extend in a first direction (i.e., a y-axis direction in
As shown in
As shown in
The sustain electrodes 16a and the scan electrodes 16b include transparent electrodes 16aa and 16ba to increase the area of the display electrodes 16 that is transparent. Since the transparent electrodes 16aa and 16ba have high resistance, the transparent electrodes 16aa and 16ba have low conductivity. On the other hand, the bus electrodes 16ab and 16bb are made of a metal, such as silver (Ag) or Cr/Cu/Cr, which has high conductivity.
As shown in
The front dielectric layer 17 is further covered with a protective layer 18. The protective layer 18 is made of a transparent material. The protective layer 18 transmits visible light emitted from the fluorescent layer 14 and protects the front dielectric layer 17 against discharge. The protective layer 18 lowers a firing voltage level by increasing a secondary electron emission coefficient. In an embodiment of the present invention, the protective layer 18 is made of magnesium oxide (MgO).
As shown in
The discharge cells 19 according to other embodiments of the present invention may have various shapes such as a stripe or delta shape. The barrier ribs 13 prevent crosstalk among the discharge cells 19. The barrier ribs 13 provide surfaces to be coated with the fluorescent layer 14.
The discharge cells 19 are filled with discharge gas that is inert gas (for example, a mixture of neon (Ne) and xenon (Xe)). The discharge gas generates discharge between the sustain electrodes 16a and scan electrodes 16b. Vacuum ultraviolet rays emitted from the discharge excite the fluorescent layer 14, thereby emitting visible light.
Referring to
The light guides 111a include incident surfaces 20 and emitting surfaces 21. Light emitted from the discharge cells 19 is incident on the incident surfaces 20. The light incident on the incident surfaces 20 passes to the outside of the filter 111 through the emitting surfaces 21.
As shown in
Super high definition images with high-pixel resolution can be displayed on the plasma display panel with the filter 111. Further, contrast is effectively maintained even in a bright room condition.
Light is not easily absorbed at the interfaces between the light guides 111a and the non-glare members 111b. Accordingly, the light does not easily disappear. The emitting surfaces 21 of the light guides 111a have a non-glare coating, so the light reflected from the plasma display panel is further reduced.
The front dielectric layer 17 according to the first embodiment of the present invention is colored with a first color (e.g., a first chromatic color). The non-glare members 111b are colored with a second color (e.g., a second chromatic color). The bus electrodes 16ab and 16bb are colored with a third color (e.g., a third chromatic color). In addition, the first to third colors are in a subtractive color mixture relationship.
By way of example, in one embodiment of the present invention, the second color of the non-glare members 111b and the third color of the bus electrodes 16ab and 16bb are in a first complementary color relationship. The third color of the bus electrodes 16ab and 16bb and the first color of the front dielectric layer 17 are in a second complementary relationship. As such, the non-glare members 111b, the bus electrodes 16ab and 16bb, and the front dielectric layer 17 are in a double complementary color relationship.
In an embodiment of the present invention, the bus electrodes 16ab and 16bb are formed as a single layer. In other embodiments, when the bus electrodes 16ab and 16bb include a black layer (not shown) and a white layer (not shown), the processes of manufacturing the bus electrodes may be complicated. When the bus electrodes 16ab and 16bb include a plurality of layers, such as a black layer and a white layer, edge curl may occur since the materials of the layers are different.
In an embodiment of the present invention, the bus electrodes 16ab and 16bb are formed as a single layer made of the same material, so the processes of manufacturing the bus electrodes 16ab and 16bb may be simplified. When patterns are exposed to light in order to form the bus electrodes 16ab and 16bb, the patterns are uniformly exposed to the light and developed by using a developer, thereby reducing undercut. In addition, since the bus electrodes 16ab and 16bb are formed as a single layer and made of the same material, edge curl less frequently occurs in the drying and annealing processes.
Types and relationships among the first color of the front dielectric layer 17, the second color of the non-glare member 111b, and the third color of the bus electrodes 16ab and 16bb will be described in detail with reference to
In an embodiment of the present invention, the light guides 111a and the non-glare members 111b may extend in the second direction (i.e., the x-axis direction in
The first embodiment of the present invention will be described in detail with reference to
As shown in
The plasma display panel includes an image display region 30 on which images are displayed. In
According to an embodiment of the present invention, when the second color of the non-glare members 111b is blue, and the third color of the bus electrodes 16ab and 16bb are yellow red, a part where the non-glare members 111b overlap the bus electrodes 16ab and 16bb appears black or substantially black. When the third color of the bus electrodes 16ab and 16bb is yellow red, and the first color of the front dielectric layer 17 is blue, a part where the bus electrodes 16ab and 16bb overlap the front dielectric layer 17 appears black or substantially black. Accordingly, a black area ratio of the plasma display panel increases, thereby improving the bright room contrast.
As described above, the first region 30a is a region where the non-glare members 111b, the bus electrodes 16ab and 16bb, and the front dielectric layer 17 overlap. Therefore, the first region 30a is in a double complementary color relationship.
According to an embodiment of the present invention, in order to color the front dielectric layer 17, the non-glare members 111b, and the bus electrodes 16ab and 16bb with the first to third colors, respectively, coloring agents may be added to the front dielectric layer 17, the non-glare members 111b, and the bus electrodes 16ab and 16bb. The coloring agents may coat the surfaces of the front dielectric layer 17, the non-glare members 111b, and the bus electrodes 16ab and 16bb or may be mixed into the respective raw materials used to form the front dielectric layer 17, the non-glare members 111b, and the bus electrodes 16ab and 16bb.
In order to be colored a shade of blue, a material selected among manganese (Mn), nickel (Ni), cobalt (Co), and combinations thereof, may be added to the layer to be colored blue or may coat the layer to be colored blue. In order to be colored a shade of yellow red, a material selected among copper (Cu), antimony (Sb), chromium (Cr), and combinations thereof, may be added to the layer to be colored yellow red or may coat the layer to be colored yellow red.
Two colors which may be mixed to form black or gray are in a complementary color relationship. As shown in
Even if colors are not in a complementary relationship, when colors which are substantially in a complementary relationship are subtractively mixed, the subtractive color mixture appears substantially black and absorbs light. For example, in
In an embodiment of the present invention, when the second color of the non-glare members 111b is a shade of blue, the third color of the bus electrodes 16ab and 16bb may be a shade of yellow red that is the complementary color of blue. In addition, the first color of the front dielectric layer 17 may be a shade of blue that is the complementary color of yellow red. Further, when the second color of the non-glare member 111b is a shade of yellow red, the third color of the bus electrodes 16ab and 16bb may be a shade of blue that is the complementary color of yellow red. The first color of the front dielectric layer 17 may be a shade of yellow red that is the complementary color of blue.
The second embodiment of the present invention will be described in detail with reference to
A filter 50 is formed on the front substrate 15. The filter 50 includes a conductive film 50b and a non-glare layer 50a, with the conductive film 50b formed on the front substrate 15. In the filter 50, the non-glare layer 50a is formed on the conductive film 50b. The conductive film 50b may be made of indium tin oxide (ITO) or mesh type copper. One side of the conductive film is grounded to a ground member.
The conductive film 50b reduces electromagnetic interference (EMI) generated in the panel by absorbing the EMI. The non-glare layer 50a may be relatively non-conductive, as compared with the conductive film 50b.
The front dielectric layer 17 according to an embodiment of the present invention is colored with the first color. The non-glare layer 50a is colored with a fourth color (e.g., fourth chromatic color). The bus electrodes 16ab and 16bb are colored with the third color. In addition, the first color, the fourth color, and the third color are in a subtractive color mixture relationship.
In an embodiment of the present invention, the fourth color of the non-glare layer 50a and the third color of the bus electrodes 16ab and 16bb are in a first complementary color relationship. The third color of the bus electrodes 16ab and 16bb and the first color of the front dielectric layer 17 are in a second complementary color relationship. As such, the non-glare layer 50a, the bus electrodes 16ab and 16bb, and the front dielectric layer 17 are in a double complementary color relationship. Further, as described above, the bus electrodes 16ab and 16bb may be formed as a single layer.
As shown in
According to the second embodiment of the present invention, when the fourth color of the non-glare layer 50a is blue and the third color of the bus electrodes 16ab and 16bb is yellow red, a part where the non-glare layer 50a overlaps the bus electrodes 16ab and 16bb appears black or substantially black. In addition, when the third color of the bus electrodes 16ab and 16bb is yellow red, and the first color of the front dielectric layer 17 is blue, a part where the bus electrodes 16ab and 16bb overlap the front dielectric layer 17 appears black or substantially black. Accordingly, the black area ratio of the plasma display panel increases, thereby improving the bright room contrast.
As shown in
In the second embodiment of the present invention, the bus electrodes 16ab and 16bb may be formed as a single layer. Since the bus electrodes 16ab and 16bb include a black layer (not shown) and a white layer (not shown), the processes of manufacturing the bus electrodes may be complicated.
The third embodiment of the present invention will be described in detail with reference to
The front dielectric layer 17, according to the third embodiment of the present invention is colored with the first color. The front substrate 15 is colored with a fifth color (e.g., a fifth chromatic color). The bus electrodes 16ab and 16bb are colored with the third color. The first color, the fifth color, and the third color are selected to be in a subtractive color mixture relationship.
In the third embodiment of the present invention, the fifth color of the front substrate 15 and the third color of the bus electrodes 16ab and 16bb are in a first complementary color relationship. The third color of the bus electrodes 16ab and 16bb and the first color of the front dielectric layer 17 are in a second complementary relationship. As such, the front substrate 15, the bus electrodes 16ab and 16bb, and the front dielectric layer 17 are in a double complementary color relationship. Further, the bus electrodes 16ab and 16bb may be formed as a single layer.
As shown in
According to the third embodiment of the present invention, when the fifth color of the front substrate 15 is blue, the third color of the bus electrodes 16ab and 16bb is yellow red, a part where the front substrate 15 overlaps the bus electrodes 16ab and 16bb represents black or substantially black. In addition, when the third color of the bus electrodes 16ab and 16bb is yellow red, and the first color of the front dielectric layer 17 is blue, a part where the bus electrodes overlap the front dielectric layer 17 represents black or substantially black. Accordingly, the light reflected from of the plasma display panel decreases, thereby improving the black area ratio and the bright room contrast.
As shown in
In the third embodiment of the present invention, the bus electrodes 16ab and 16bb may be formed as a single layer. Since the bus electrodes 16ab and 16bb include a black layer (not shown) and a white layer (not shown), the processes of manufacturing the bus electrodes may be complicated.
While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, and equivalents thereof.
Number | Date | Country | Kind |
---|---|---|---|
10-2006-0107975 | Nov 2006 | KR | national |