This application claims priority from Korean Patent Application No. 10-2009-0055508, filed on Jun. 22, 2009, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.
1. Field of the Invention
Apparatuses and methods consistent with the present invention relate to a plasma display apparatus, and more particularly, to a plasma display apparatus for preventing electromagnetic interference.
2. Description of the Related Art
A plasma display apparatus displays an image using plasma generated from a gas discharge. Plasma display apparatuses are the next generation of display apparatuses because they are slim, light-weight, and can accommodate a large screen size. As a result, there are many studies on these plasma display apparatus.
However, with the current plasma display apparatus, electromagnetic wave noise occurs when the plasma display apparatus is driven, causing electromagnetic interference. To solve this problem, the related-art discloses a plasma display apparatus that is equipped with an electromagnetic wave shielding filter on a front surface of a plasma display panel to prevent the electromagnetic interference. However, the electromagnetic wave shielding filter deteriorates brightness of an image. Also, an electromagnetic wave shielding filter increases a manufacturing cost of plasma display apparatuses.
Accordingly, there is a demand for a plasma display apparatus that can prevent electromagnetic interference without the addition of an electromagnetic wave shielding filter.
Exemplary embodiments of the present invention overcome the above disadvantages and other disadvantages not described above. Also, the present invention is not required to overcome the disadvantages described above, and an exemplary embodiment of the present invention may not overcome any of the problems described above.
Exemplary embodiments of the present invention provide a plasma display apparatus for preventing electromagnetic interference.
According to an aspect of the present invention, there is provided a plasma display apparatus including a first substrate and a second substrate which face each other with a predetermined gap therebetween, a plurality of X electrodes and a plurality of Y electrodes which are alternately arranged on the first substrate along a first direction, a plurality of address electrodes which are arranged on the second substrate along a second direction which intersects with the first direction, and an address driver which drives the plurality of address electrodes.
At least one address electrode may be connected to the address driver through one end of the second direction of the second substrate, and an address electrode neighboring the at least one address electrode may be connected to the address driver through other end of the second direction of the second substrate.
The plurality of address electrodes may be alternately connected to the address driver through one end and the other end of the second direction of the second substrate.
A predetermined number of continuous address electrodes may form an address electrode group, and a plurality of address electrode groups may be alternately connected to the address driver through one end and the other end of the second direction of the second substrate.
The address driver may include a first address driver which drives an address electrode connected thereto through one end of the second direction of the second substrate, and a second address driver which drives an address electrode connected thereto through the other end of the second direction of the second substrate.
The plasma display apparatus may further include an X driver which drives the plurality of X electrodes, and a Y driver which drives the plurality of Y electrodes.
The plasma display apparatus may further include a controller which generates a control signal by processing input video data, and transmits the control signal to the address driver, the X driver, and the Y driver.
The above and/or other aspects of the present invention will become more apparent by describing certain exemplary embodiments of the present invention with reference to the accompanying drawings, in which:
Exemplary embodiments of the present invention are described in greater detail below with reference to the accompanying drawings.
In the following description, the same drawing reference numerals are used for the like or same elements even in different drawings. The matters defined in the description, such as detailed construction and elements, are provided to assist in a comprehensive understanding of the invention. However, the present invention can be practiced without those specifically defined matters. Also, well-known functions or constructions are not described in detail since they would obscure the invention with unnecessary detail.
As shown in
The plasma display panel 100 includes a first substrate 110, a second substrate 120, an X electrode 130, a Y electrode 140, and an address electrode 150, as shown in
The first substrate 110 and the second substrate 120 face each other such that there is a predetermined gap between the first substrate 110 and the second substrate 120. Gas discharge is performed in the space between the first substrate 110 and the second substrate 120. Visible rays generated by the gas discharge are emitted to the outside through the first substrate 110. Therefore, the first substrate 110 is formed of a transparent material or a semitransparent material.
The X electrode 130 is arranged on the first substrate 110 along a first direction (x direction of
The Y electrode 140 is arranged on the first substrate 110 in parallel to the X electrode 130. The Y electrode may be called a scan electrode. As shown in
A first dielectric layer 111 is formed on the same surface of the first substrate 110 on which the X electrode 130 and the Y electrode 140 are arranged. The first dielectric layer 111 prevents the X electrode 130 and the Y electrode directly conducting when sustained discharge occurs, and prevents charged particles from directly colliding with the X electrode 130 and the Y electrode 140. The first dielectric layer 111 comprises lead oxide (PbO), diboron trioxide (B2O3), and silicon dioxide (SiO2).
A protective layer 112 is formed on the first dielectric layer 111. The protective layer 112 prevents the X electrode 130 and the Y electrode 140 from being damaged by sputtering of plasma particles. The protective layer 112 also discharges secondary electrons to lower the discharge voltage. The protective layer 112 may comprise magnesium oxide (MgO).
The address electrode 150 is arranged on the second substrate 120 along a second direction (y direction of
As shown in
A partition 155 is formed on the second dielectric layer 151 and forms a plurality of discharge cells 156. The gas discharge is performed in the discharge cells 156 by filling the discharge cells 156 with discharge gases, such as argon, neon, and xenon. The partition 155 prevents electrical and optical cross-talk between the discharge cells 156.
A fluorescent substance is coated over the upper surface of the second dielectric layer 151 and the lateral surfaces of the partition 155, thereby forming a fluorescent layer 157. The fluorescent layer 157 is excited by ultraviolet rays generated during the gas discharge to produce visible rays, which are emitted to the outside through the first substrate 110. The fluorescent substance of Y(V,P)O4:Eu may be used to express red color, the fluorescent substance of Zn2SiO4:Mn may be used to express green color, and the fluorescent substance of BAM:Eu may be used to express blue color.
The controller 200 controls the plasma display panel 100 to display an image on the plasma display panel 100. That is, the controller 100 generates a control signal by processing video data input from an external source and transmitting the control signal to the first and the second address drivers 300, 400, the X driver 500, and the Y driver 600. The control signal includes first and second address signals Sa1, Sa2 for the first and the second address drivers 300, 400, an X driving signal Sx for the X driver 500, and a Y driving signal Sy for the Y driver 600.
The first address driver 300 drives the address electrodes A1R, A1B, . . . , ANG, which are connected thereto through one end 121 of the second direction (y direction of
The second address driver 400 drives the address electrodes A1G, A2R, . . . , ANB, which are connected thereto through the other end 122 of the second direction (y direction of
The X driver 500 drives the X electrode 130 according to the X driving signal Sx transmitted from the controller 200, and the Y driver 600 drives the Y electrode 140 according to the Y driving signal Sy transmitted from the controller 200.
Hereinafter, the arrangement of the address electrodes A1R, A1G, A1B, A2R, A2G, A2B, . . . , ANR, ANG, ANB according to an exemplary embodiments of the present invention will be explained. The subscript “R” means that the address electrode corresponds to a discharge cell which discharges red visible rays, the subscript “G” means that the address electrode corresponds to a discharge cell which discharges green visible rays, and the subscript “B” means that the address electrode corresponding to a discharge cell which discharges blue visible rays. As shown in
The operation of the plasma display apparatus 100 is well known to those skilled in the related art and thus will be explained briefly. If a predetermined address voltage is applied between the address electrode 150 and the X electrode 130, address discharge occurs, and consequently, a discharge cell is selected in which sustained discharge occurs. Then, if a sustained discharge voltage is applied between the X electrode 130 and the Y electrode 140 in the selected discharge cell, wall charge accumulates on the X electrode 130 and the Y electrode 140 moves, causing sustained discharge. An energy level of discharged gas excited by the sustained discharge is lowered such that ultraviolet rays are discharged. The ultraviolet rays excite the fluorescent substance of the fluorescent layer 157 in the discharge cell, and the energy level of the excited fluorescent substance is lowered such that visible rays are emitted. As a result, unwanted electromagnetic wave noise occurs during the operation of the plasma display apparatus, causing electromagnetic interference.
The operation of reducing the electromagnetic interference of the plasma display apparatus 10 according to an exemplary embodiment of the present invention will be explained with reference to two neighboring address electrodes ANG, ANB of
First, the operation of reducing the noise which occurs during the sustained discharge is explained. The inventor of the present invention comes to know that the noise, which occurs in the X electrode 130 and the Y electrode 140 during the sustained discharge (called a sustained noise) propagates towards the address electrodes A1R, A1G, A1B, A2R, A2G, A2B, . . . , ANR, ANG, ANB which are maintained in a ground state during the sustained discharge, such that a vertical (y direction) radiation noise becomes the dominant noise source. Such noise is treated as common-mode noise. As described above, the first address electrode ANG is connected to the first address driver 300 through one end 121 of the y direction of the second substrate 120, and the second address electrode ANB, neighboring the first address electrode ANG, is connected to the second address driver 400 through the other end 122 of the y direction of the second substrate 120. Accordingly, the sustained noise induced toward the first address electrode ANG has a direction indicated by an arrow 126, and the sustained noise induced toward the second address electrode ANB has a direction indicated by an arrow 127. That is, since the sustained noises propagated toward the two neighboring address electrodes ANG, ANB, which have opposite directions, are offset by each other thus reducing the radiation noise.
Second, the operation of reducing the noise which occurs when the address electrodes are driven will be described. As shown in
Although only the two address electrodes ANG, ANB are explained for the sake of simplicity, the same mechanism is applied to other address electrodes shown in
This embodiment differs from the aforementioned embodiment in arrangement of address electrodes. That is, a predetermined number of continuous address electrodes form an address electrode group, which are alternately connected to the first and the second address drivers 300, 400 through one end 121 and the other end 122 of the y direction of the second substrate 120. Referring to
In the same manner as that of the aforementioned embodiment, sustained noise propagates in the neighboring first and second address electrode groups AG1, AG2 during the sustained discharge in opposite directions, and electric current flows in the first and the second address electrode groups AG1, AG2 when the address electrodes are driven in opposite directions, so that noise can be greatly reduced.
Although in the embodiment shown in
This embodiment differs from the aforementioned embodiments in that there is only a single address driver 300′, not two address drivers. However, in the same manner as in the embodiment of
Since the embodiment of
This embodiment differs from the aforementioned embodiments in the arrangement of the address electrodes. That is, an address electrode A1R, A2R, . . . , ANR, corresponding to a discharge cell discharging red visible rays, is connected to the first address driver 300 through one end 121 of y direction of the second substrate 120 and the other address electrode A1G, A1B, A2G, A2B, . . . ANG, ANB, corresponding to discharge cells discharging green and blue visible rays, is connected to the second address driver 400 through the other end 122 of the y direction of the second substrate 120. For the same reason as that of the aforementioned embodiments, the noise is reduced in the embodiment of
Although in the embodiment of
The foregoing exemplary embodiments and advantages are merely exemplary and are not to be construed as limiting the present invention. The present teaching can be readily applied to other types of apparatuses. Also, the description of the exemplary embodiments of the present invention is intended to be illustrative, and not to limit the scope of the claims, and many alternatives, modifications, and variations will be apparent to those skilled in the art.
Number | Date | Country | Kind |
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10-2009-0055508 | Jun 2009 | KR | national |