This application claims the benefit of Korean Patent Application No. 10-2008-0076850 filed on Aug. 6, 2008, the entire contents of which is hereby incorporated by reference.
1. Field
Embodiments relate to a plasma display panel.
2. Description of the Background Art
A plasma display panel includes a phosphor layer inside discharge cells partitioned by barrier ribs and a plurality of
When driving signals are applied to the electrodes of the plasma display panel, a discharge occurs inside the discharge cells. More specifically, when the discharge occurs in the discharge cells by applying the driving signals to the electrodes, a discharge gas filled in the discharge cells generates vacuum ultraviolet rays, which thereby cause phosphors between the barrier ribs to emit visible light. An image is displayed on the screen of the plasma display panel using the visible light.
In one aspect, a plasma display panel comprises a front substrate, scan electrodes and sustain electrodes that are positioned on the front substrate substantially parallel to each other, a rear substrate opposite the front substrate, a barrier rib on the rear substrate, a black layer opposite the barrier rib, the black layer being positioned on the front substrate substantially parallel to the scan electrode and the sustain electrode, the black layer including a first black layer between the two adjacent scan electrodes and a second black layer between the two adjacent sustain electrodes, and an auxiliary electrode on the second black layer.
In another aspect, a plasma display panel comprises a front substrate, scan electrodes and sustain electrodes that are positioned on the front substrate substantially parallel to each other, a rear substrate opposite the front substrate, a barrier rib on the rear substrate, a black layer opposite the barrier rib, the black layer being positioned on the front substrate substantially parallel to the scan electrode and the sustain electrode, the black layer including a first black layer between the two adjacent scan electrodes and a second black layer between the two adjacent sustain electrodes, a width of the second black layer being greater than a width of the first black layer, and an auxiliary electrode on the second black layer.
In still another aspect, a plasma display panel comprises a front substrate, scan electrodes and sustain electrodes that are positioned on the front substrate substantially parallel to each other, the scan electrodes and the sustain electrodes being bus electrodes, a rear substrate opposite the front substrate, a barrier rib on the rear substrate, a black layer opposite the barrier rib, the black layer being positioned on the front substrate substantially parallel to the scan electrode and the sustain electrode, the black layer including a first black layer between the two adjacent scan electrodes and a second black layer between the two adjacent sustain electrodes, a width of the second black layer being greater than a width of the first black layer, and an auxiliary electrode on the second black layer.
The accompany drawings, which are included to provide a further understanding of the invention and are incorporated on and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. In the drawings:
Reference will now be made in detail embodiments of the invention examples of which are illustrated in the accompanying drawings.
As shown in
An upper dielectric layer 104 may be formed on the scan electrode 102 and the sustain electrode 103 to limit a discharge current of the scan electrode 102 and the sustain electrode 103 and to provide insulation between the scan electrode 102 and the sustain electrode 103.
A protective layer 105 may be formed on the upper dielectric layer 104 to facilitate discharge conditions. The protective layer 105 may be formed of a material having a high secondary electron emission coefficient, for example, magnesium oxide (MgO).
A lower dielectric layer 115 may be formed on the address electrode 113 to provide insulation between the address electrodes 113.
Barrier ribs 112 of a stripe type, a well type, a delta type, a honeycomb type, etc. may be formed on the lower dielectric layer 115 to partition discharge spaces (i.e., discharge cells). Hence, a first discharge cell emitting red light, a second discharge cell emitting blue light, and a third discharge cell emitting green light, etc. may be formed between the front substrate 101 and the rear substrate 111.
The barrier rib 112 may include first and second barrier ribs 112a and 112b crossing each other. Heights of the first and second barrier ribs 112a and 112b may be different from each other. The first barrier rib 112a may be parallel to the scan electrode 102 and the sustain electrode 103, and the second barrier rib 112b may be parallel to the address electrode 113.
The height of the first barrier rib 112a may be less than the height of the second barrier rib 112b. Hence, in an exhaust process and a process for infecting a discharge gas, an impurity gas in the panel 100 may be efficiently exhausted to the outside of the panel 100, and the discharge gas may be uniformly injected. Each of the discharge cells partitioned by the barrier ribs 112 may be filled with the discharge gas.
A phosphor layer 114 may be formed inside the discharge cells to emit visible light for an image display during an address discharge. For example, first, second, and third phosphor layers that respectively generate red, blue, and green light may be formed inside the discharge cells.
While the address electrode 113 may have a substantially constant width or thickness, a width or thickness of the address electrode 113 inside the discharge cell may be different from a width or thickness of the address electrode 113 outside the discharge cell. For example, a width or thickness of the address electrode 113 inside the discharge cell may be greater than a width or thickness of the address electrode 113 outside the discharge cell.
An auxiliary electrode 106 may be positioned on the front substrate 101 parallel to the scan electrode 102 and the sustain electrode 103.
As shown in
The auxiliary electrode 106 may prevent charges from moving between the adjacent discharge cells to contribute to a prevention of crosstalk. The auxiliary electrode 106 may be formed of a material with excellent electrical conductivity, for example, silver (Ag), gold (Au), copper (Cu), aluminum (Al).
The upper dielectric layer 104 may be positioned on the second black layer 108 on which the auxiliary electrode 106 is positioned, the first black layer 107, the scan electrode 102, and the sustain electrode 103. The scan electrode 102 and the sustain electrode 103 may include transparent electrodes 102a and 103a and bus electrodes 102b and 103b.
The transparent electrodes 102a and 103a may be formed of a transparent material, for example, indium-tin-oxide (ITO). The bus electrodes 102b and 103b may be formed of a material with electrical conductivity, such as Ag to improve electrical conductivity of the scan and sustain electrodes 102 and 103. The bus electrodes 102b and 103b may be formed of the same material as the auxiliary electrode 106.
A third black layer 200 may be positioned between the transparent electrode 102a and the bus electrode 102b of the scan electrode 102, and a fourth black layer 210 may be positioned between the transparent electrode 103a and the bus electrode 103b of the sustain electrode 103.
When the first, second, third, and fourth black layers 107, 108, 200, and 210 are positioned as above, a reflection of light coming from the outside may be prevented. Contrast characteristics of a displayed image may be improved.
It may be preferable that a width of the auxiliary electrode 106 may be less than or substantially equal to a width of the second black layer 108, so as to improve the contrast characteristics by preventing light from the outside from being reflected by the auxiliary electrode 106.
The auxiliary electrode 106 and the first and second black layers 107 and 108 may be simultaneously fired, so as to reduce time required in a manufacturing process and reduce the manufacturing cost. The auxiliary electrode 106, the first, second, third, and fourth black layers 107, 108, 200, and 210, and the bus electrodes 102b and 103b may be simultaneously fired.
As shown in
More specifically, the rising signal RS may be supplied to the scan electrode Y during a setup period SU of the reset period RP, and the falling signal FS may be supplied to the scan electrode Y during a set-down period SD following the setup period SU. The rising signal RS may generate a weak dark discharge (i.e., a setup discharge) inside the discharge cells. Hence, the remaining wall charges may be uniformly distributed inside the discharge cells. The falling signal FS may generate a weak erase discharge (i.e., a set-down discharge) inside the discharge cells. Hence, the remaining wall charges may be uniformly distributed inside the discharge cells to the extent that an address discharge occurs stably.
During an address period AP following the reset period RP, a scan bias signal Vsc having a voltage greater than a minimum voltage of the falling signal FS may be supplied to the scan electrode Y. A scan signal Scan falling from the scan bias signal Vsc may be supplied to the scan electrode Y during the address period AP.
A pulse width of a scan signal supplied to the scan electrode during an address period of at least one subfield of a frame may be different from pulse widths of scan signals supplied during address periods of other subfields of the frame. A pulse width of a scan signal in a subfield may be greater than a pulse width of a scan signal in a next subfield. For example, a pulse width of the scan signal may be gradually reduced in the order of 2.6 μs, 2.3 μs, 2.1 μs, 1.9 μs, etc., or may be reduced in the order of 2.6 μs, 2.3 μs, 2.3 μs, 2.1 μs, . . . , 1.9 μs, 1.9 μs, etc. in the successively arranged subfields.
When the scan signal Scan is supplied to the scan electrode Y, a data signal Data corresponding to the scan signal Scan may be supplied to the address electrode X. As the voltage difference between the scan signal Scan and the data signal Data is added to a wall voltage by the wall charges produced during the reset period RP, an address discharge may occur inside the discharge cells to which the data signal Data is supplied.
During a sustain period SP following the address period AP, a sustain signal SUS may be supplied to at least one of the scan electrode Y or the sustain electrode Z.
As shown in
Unlike a description of
As above, the auxiliary electrode 106 may prevent charges from moving between the adjacent discharge cells to contribute to the prevention of crosstalk.
If the auxiliary electrode is not formed as shown in (a) of
On the other hand, if the auxiliary electrode 106 is formed as shown in (b) of
It may be advantageous in an exhaust process and a process for injecting a discharge gas that the height of the first barrier rib 112a parallel to the scan electrode 102 and the sustain electrode 103 is less than the height of the second barrier rib 112b parallel to the address electrode 113. However, because charges easily move between the adjacent discharge cells, crosstalk may increase. Accordingly, when the height of the first barrier rib 112a is less than the height of the second barrier rib 112b, it may be preferable that the auxiliary electrode 106 is provided.
As shown in
Further, the width W1 of the second black layer 108 may be substantially equal to the width W3 of the auxiliary electrode 106. In this case, the contrast characteristics may be improved.
The widths W1, W2, and W3 of the second black layer 108, the first black layer 107, and the auxiliary electrode 106 are widths measured in a direction crossing the scan electrode 102 and the sustain electrode 103.
The width W1 of the second black layer 108 may be greater than the width W2 of the first black layer 107. This reason will be described with reference to
On the other hand,
As shown in
When the width W1 of the second black layer 108 on which the auxiliary electrode 106 is positioned is greater than the width W2 of the first black layer 107 on which the auxiliary electrode 106 is not positioned as shown in
An amount of light may unnecessarily increase in a portion in which the auxiliary electrode 106 is positioned. As a result, the contrast characteristics may be reduced. However, light may be prevented from unnecessarily increasing in the portion in which the auxiliary electrode 106 is positioned by allowing the width W1 of the second black layer 108 overlapping the auxiliary electrode 106 to be greater than the width W2 of the first black layer 107. As a result, a reduction in the contrast characteristics may be prevented.
As shown in
The first and second black layers 107 and 108 may be spaced apart from the scan and sustain electrodes 102 and 103 adjacent to the first and second black layers 107 and 108. For example,
Because the width of the second black layer 108 is greater than the width of the first black layer 107, the distances d1 and d2 between the second black layer 108 and the sustain electrodes 103 may be shorter than the distances d3 and d4 between the first black layer 107 and the scan electrodes 102. The distances d1 and d2 may be substantially equal to or different from each other, and the distances d3 and d4 may be substantially equal to or different from each other.
The first black layer 107 may be spaced apart from the scan and sustain electrodes 102 and 103 adjacent to the first black layer 107, and the second black layer 108 may be poisoned to be connected to at least one scan electrode 102 or at least one sustain electrode 103 adjacent to the second black layer 108. For example,
The two scan electrodes may be adjacently positioned, and the two sustain electrodes may be adjacently positioned. For example,
In the above electrode arrangement, it may be preferable that the auxiliary electrode 106 is positioned between the two adjacent sustain electrodes. Namely, the second black layer is positioned between the two adjacent sustain electrodes, and the auxiliary electrode 106 is positioned on the second black layer.
In the above electrode arrangement, the drive efficiency may be improved by reducing a capacitance between the two adjacent scan electrodes and a capacitance between the two adjacent sustain electrodes. Further, the crosstalk may be reduced by reducing a voltage difference between the two adjacent scan electrodes and a voltage difference between the two adjacent sustain electrodes during a discharge.
In this case, a movement of charges 1100 between the adjacent discharge cells may briskly occurs. For example, if a sustain discharge occurs between the scan electrode Y2 and the sustain electrode Z2 as shown in
On the other hand, as shown in
A reason why the auxiliary electrode 106 is positioned between the two adjacent sustain electrodes will be described with reference to
For example, when a first scan signal Scan1 is supplied to the scan electrode Y1, an address discharge may occur by a voltage difference between a data signal supplied to the address electrode X1 and the first scan signal Scan1. Further, when a second scan signal Scan2 is supplied to the scan electrode Y2, an address discharge may occur by a voltage difference between the data signal supplied to the address electrode X1 and the second scan signal Scan2.
When the address discharge occurs by the first scan signal Scan1 and the data signal, a first falling signal fs1 may be produced in the first auxiliary electrode 106a by a voltage of the first scan signal Scan1. A voltage of the first falling signal fs1 affects the scan electrode Y2 adjacent to the first auxiliary electrode 106a, and thus a distribution state of wall charges on the scan electrode Y2 may be non-uniform. Hence, the address discharge generated by the second scan signal Scan2 and the data signal may be unstable. Even if the voltage of the first falling signal fs1 has a excessively great value, an erroneous discharge may occur between the scan electrode Y2 or the first auxiliary electrode 106a and the address electrode when the address discharge occurs by the first scan signal Scan1 and the data signal.
As above, when the auxiliary electrode is positioned between two scan electrodes, the address discharge may unstably occur or the erroneous discharge may occur. Therefore, it is preferable that the auxiliary electrode is positioned between two sustain electrodes as shown in
At least one of the first and second black layers 107 and 108 may include first and second portions each having a different width. For example,
Because the second black layer 108 includes the first portion 108a and the second portion 108b as shown in
The second portions of the first and second black layers 107 and 108 may be positioned at a crossing of the first and second barrier ribs 112a and 112b.
As above, when at least one of the first and second black layers 107 and 108 includes the first and second portions, a black area may increase. Hence, the contrast characteristics may be improved. Further, when the second portion of the auxiliary electrode is positioned at the crossing of the first and second barrier ribs 112a and 112b, a black area may increase while a reduction in an aperture ratio is prevented. Hence, the contrast characteristics may be further improved.
As shown in
As above, when the width W3 of the auxiliary electrode 106 is greater than the width W4 of the bus electrode 103b, a charge capacity of the auxiliary electrode 106 may sufficiently increase. Therefore, charge may be prevented from moving between the adjacent discharge cells, and the crosstalk may be reduced.
As shown in
When the width W3 of the auxiliary electrode 106 is equal to or greater than the upper width W5 of the first barrier rib 112a and is equal to or less than the lower width W6 of the first barrier rib 112a, electrical short circuit between the auxiliary electrode 106 and the scan electrode 102 or the sustain electrode 103 adjacent to the auxiliary electrode 106 may be prevented while charge are prevented from moving between the adjacent discharge cells.
As shown in
As shown in
Considering this, it may be preferable that the width W3 of the auxiliary electrode 106 is equal to or greater than the upper width W5 of the first barrier rib 112a and is equal to or less than the lower width W6 of the first barrier rib 112a.
As shown in
As shown in
The scan electrode 102 and the sustain electrode 103 including the bus electrodes 102b and 103b may be formed of a material with excellent electrical conductivity that is easy to mold, for example, silver (Ag), gold (Au), copper (Cu), aluminum (Al).
As shown in
The above-described description may be applied to the plasma display panel illustrated in
Any reference in this specification to “one embodiment,” “an embodiment,” “example embodiment,” etc., means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with any embodiment, it is submitted that it is within the purview of one skilled in the art to effect such feature, structure, or characteristic in connection with other ones of the embodiments.
Although embodiments have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the scope of the principles of this disclosure. More particularly, various variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the disclosure, the drawings and the appended claims. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art.
Number | Date | Country | Kind |
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10-2008-0076850 | Aug 2008 | KR | national |