This application claims the priority benefit of Taiwan application serial no. 941 22518, filed on Jul. 4, 2005. All disclosure of the Taiwan application is incorporated herein by reference.
1. Field of the Invention
The present invention relates to a display device, and more particularly, to a display device, a plasma display panel, and a front substrate thereof capable of improving the problem due to crowded current on the trace.
2. Description of the Related Art
Along with the multimedia development, a display device, serving as a communication interface between human and computer, has played a more and more significant role now. Recently, panel display had been widely used to replace the traditional CRT (Cathode Ray Tube) display. The panel display currently used is mainly divided into following categories: Plasma display panel, Organic Electro-Luminescent Display (OELD), and Liquid Crystal Display (LCD), etc. Wherein, due to its advantageous of large size, self-emitting, no view-angle dependence, thinner and lighter, full color, and great potential in application, the plasma display panel may gradually become a mainstream product of next generation panel display.
Generally, a plasma display panel should pass an aging test before it is sent out from the factory, the aging test is to make the emitting status of each pixel stable. Regarding the plasma display panel mentioned above, the aging testing is performed by placing a metal plate on the traces 108 first. Then, a voltage is provided onto the metal plate such that a current is provided to all of the traces 108, the bus electrode 106 and all of the Y electrodes 104. However, since the Y electrodes 104 on the band 112 are near to the trace 108a, a majority of the current is provided into the Y electrodes 104 on the band 112 via the trace 108a. In other words, a crowded current phenomenon occurs on the trace 108a, which further causes increases the temperature at the peripheral of the trace 108a on the substrate 100 and a differential temperature around the trace 108a and also other areas, which may cause cracking on the panel. It is known from physical measurement, the temperature at the peripheral of the trace 108a on the substrate 100 is about 50 to 60° C. higher than the temperature on other areas of the substrate 100, and the temperature around the trace 108a of the substrate 100 may be as higher as 109° C.
Similarly, since the Y electrodes 104 on the band 114 are near to the trace 108b, a majority of the current is provided into the Y electrodes 104 on the band 114 via the trace 108b. Accordingly, an increase in temperature may occur on the peripheral of the trace 108b on the substrate 100 due to the crowded current effect, which may further cause cracking on the panel.
Therefore, the present invention is directed to a display device, wherein the crowded current phenomenon is suppressed.
The present invention is directed to a front substrate of a plasma display panel capable of reducing cracking on the panel during the aging test.
The present invention is directed to a plasma display panel capable of suppressing the crowded current problem therein, and providing same level of the voltage pulses onto the electrodes of each pixel so as to make the emitting status of the display stable.
As embodied and broadly described herein, the present invention provides a display device. The display device mainly comprises a display portion and a peripheral circuit portion. Wherein, the display portion comprises a plurality of electrodes and can be further divided into a plurality of bands. The peripheral circuit portion comprises a plurality of bus electrodes and a plurality of traces. One end of each of the bus electrodes is electrically connected to a portion of the electrodes that is located on one of the bands of the display portion, and the other end of each of the bus electrodes is electrically connected to one of the traces.
As embodied and broadly described herein, the present invention provides a front substrate of a plasma display panel. The front substrate of the plasma display panel mainly comprises a substrate, a plurality of electrode pairs, a plurality of bus electrodes and a plurality of traces. Wherein, the substrate comprises a display area and a peripheral circuit area and the display area can be further divided into a plurality of bands. The electrodes are disposed on the display area of the substrate, and each set of the electrode pair, for example, comprises a Y electrode and an X electrode, wherein at least one set of the electrode pair is disposed on each band of the display area. The bus electrodes are disposed in the peripheral circuit area of the substrate, wherein one end of each of the bus electrodes is electrically connected to a portion of the Y electrodes that is located on a band of the display area, and the other end of each of the bus electrodes is electrically connected to one of the traces.
As embodied and broadly described herein, the present invention provides a plasma display panel. The plasma display panel mainly comprises a rear substrate and a front substrate, which is disposed above the rear substrate. Wherein, the rear substrate comprises a first substrate, a plurality of address electrodes, a rib and a fluorescent material layer. The address electrodes and the rib are respectively disposed on the first substrate, wherein the rib is used to define a plurality of discharge spaces on the first substrate, and each of the address electrode discharge spaces is disposed on one of the discharge spaces. The fluorescent material layer is disposed on the discharge spaces and located on the address electrodes and a sidewall of the rib. The front substrate comprises a second substrate, a plurality of electrode pairs, a plurality of bus electrodes and a plurality of traces. Wherein, the second substrate comprises a display area and a peripheral circuit area, and the display area can be further divided into a plurality of bands. The electrodes pairs are disposed on the display area of the second substrate, wherein each set of the electrode pair, for example, comprises an X electrode and a Y electrode, and at least one set of electrode pair is disposed on each band of the display area. The bus electrodes are disposed on the peripheral circuit area of the second substrate, wherein one end of each of the bus electrodes is electrically connected to the Y electrodes inside an area of the display area, and the other end of each of the bus electrodes is electrically connected to one of the traces.
In accordance with an embodiment of the present invention, the resistances of the bus electrodes may be the same or different, and in the case of the resistances of the bus electrodes are not the same, the variation may be, for example, less than 10%. In an embodiment of the present invention, the bus electrode may be a trapezoid or a polygon.
In accordance with an embodiment of the present invention, the front substrate of the plasma display panel mentioned above further comprises a passivation layer, which is disposed on the substrate for covering the electrode pairs. In an embodiment of the present invention, the front substrate of the plasma display panel mentioned above further comprises a dielectric layer, which is disposed on the substrate for covering the electrode pairs, and the dielectric layer is disposed between the passivation layer and the substrate.
In accordance with an embodiment of the present invention, the plasma display panel mentioned above further comprises a first dielectric layer, which is disposed on the first substrate for covering the address electrodes, and the rib is disposed on the first dielectric layer.
In the present invention, the conventional bus electrodes are divided into a plurality of bus electrodes in order to reduce the number of the electrodes electrically connected to each of the bus electrodes, and further to reduce the amount of the current loading on each trace during the transfer of signal to the electrodes. Therefore, the problem due to crowded current on a single trace can be suppressed, and the cracking on the plasma display panel due to increasing differential temperature between the point where the current is crowded and other points can be reduced.
The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention, and together with the description, serve to explain the principles of the invention.
In the present invention, the electrodes in the display portion of the display device are divided into a plurality of sets, and each set of the electrodes is electrically connected to the traces via the corresponding bus electrodes, so as to reduce the number of the electrodes electrically connected to each of the bus electrodes and further to reduce the problem of crowded current. The plasma display panel is exemplified hereinafter for description. However, the embodiment described below is for describing the present invention and the present invention is not necessarily to be limited by it. Accordingly, it will be apparent to one ordinary skill in the art that the display device of the present invention is not limited to the plasma display panel only.
Referring to
It should be noted that the number and shape of the bus electrodes 226 are not limited in the present invention. For example, the number of the bus electrodes 226 formed in the plasma display panel 200 is 4 as shown in
In summary, in the present invention, the conventional bus electrodes are divided into a plurality of bus electrodes in order to reduce the number of the electrodes electrically connected to each of the bus electrodes, and further to reduce the amount of the current loading on each trace during the transfer of signal to the electrodes. Therefore, the problem of crowded current on the single trace can be reduced, and the cracking problem due to increased differential temperature between the area where the current is crowded and other areas can be reduced.
In addition, since the values of resistance of the bus electrodes in the present invention are close to each other, its variation is less than 10% for example, such that the voltage pulse with similar level is applied onto the electrodes electrically connected to each of the bus electrodes. Therefore, the discharge of each pixel in the display device of the present invention is stable after it had passed the aging test, such that the insufficient writing problem is avoided.
Although the invention has been described with reference to a particular embodiment thereof, it will be apparent to one of the ordinary skill in the art that modifications to the described embodiment may be made without departing from the spirit of the invention. Accordingly, the scope of the invention will be defined by the attached claims not by the above detailed description.
Number | Date | Country | Kind |
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94122518 | Jul 2005 | TW | national |