Patent Application
20100237759
1. Field of the Invention
The present invention relates to a large-screen display device configured with a plurality of plasma tube array-type display sub-modules connected to one another. More particularly, the present invention relates to a display device in which the plasma tube array-type display sub-modules that compose a plasma tube array-type display system module are commonized to be attachable or detachable.
2. Description of the Related Art
Plasma tube array-type display sub-modules (hereinafter referred to as “PTA sub-modules”) have been developed as a technology for providing new-generation large-screen display devices. The PTA sub-modules each include a plurality of plasma tubes filled with a discharge gas that are arranged in parallel. For example, a plasma tube array-type display system module (hereinafter referred to as a “PTA system module”) in which a plurality of PTA sub-modules, each of which is one meter square, are connected to one another can be used to construct a large-screen display device with a size of several meters by several meters. In the case of a display device including a plurality of PTA sub-modules that are connected to one another, it is not necessary to handle a large glass substrate and no large-scale equipment is required as in the case of, for example, LCDs and PDPs. Therefore, a display device with uniform image quality can be provided at a lower cost.
As the detail of a part thereof is shown in
On the other hand, the PTA sub-module 1c located furthest to the right in the PTA system module is formed in such a manner that X electrodes 15, 15, . . . and Y electrodes 16, 16, . . . are led out to the same position at the left end, while at the right end, the Y electrodes 16 are lead out longer to the right side than the X electrodes 15 with the lead-out ends serving as Y electrode terminals. The Y electrode terminals led out longer are connected to a Y drive circuit 13 through a connector for the Y electrodes. Furthermore, the center PTA sub-module 1b located between the PTA sub-modules 1a and 1c is formed in such a manner that X electrodes 15, 15, . . . and Y electrodes 16, 16, . . . are lead out to the same positions at the left and right ends, with the lengths thereof being the same.
As described above, in the case of the conventional PTA sub-modules 1, 1, . . . , three types of PTA sub-modules 1a, 1b, and 1c comprising the display electrodes 10a, 10b, and 10c, respectively formed in different arrangement patterns are prepared according to the arrangement thereof. These are connected by connectors 14 and 14, so that one PTA system module for a large screen is composed.
The connectors 14, each of which connects the PTA sub-modules 1 and 1 to each other, connect the X electrodes and the Y electrodes of the display electrodes 10a, 10b, and 10c bent toward the rear side between adjacent PTA sub-modules 1, 1, . . . together with the front-side flexible supporting sheets FF shown in
In the configuration shown in
However, when a PTA system module for a large screen is composed of a plurality of PTA sub-modules 1, 1, . . . connected laterally to one another, it is necessary to clearly distinguish among the right PTA sub-module 1a to be connected to the X drive circuit 12, the left PTA sub-module 1c to be connected to the Y drive circuit 13, and the center PTA sub-module 1b to be located at the center and to be connected to adjacent left and right PTA sub-modules 1a and 1c. Furthermore, there has been a problem in that even when a failure occurs in only one of the PTA sub-modules 1a, 1b, and 1c after the PTA system module is assembled, it can be replaced only with the same type of the PTA sub-module 1a, 1b, or 1c and therefore maintenance is troublesome.
Moreover, in the case where at least two PTA sub-modules 1 and 1 are connected laterally to each other, in the conventional configuration in which the display electrodes for X electrodes and Y electrodes are connected to each other between adjacent PTA sub-modules 1 and 1, although both the gap between adjacent terminals of the connector 14a and the gap between adjacent terminals of the connector 14b are minute, as small as 1 mm or smaller, it is necessary to satisfy withstand voltage characteristics that a maximum potential difference between the X electrode and the Y electrode is 600V or more. Therefore, in order to satisfy the withstand voltage characteristics, the connectors 14a and 14b are required to have costly configurations.
The present invention was made with such situations in mind. The present invention is intended to provide plasma tube array-type display sub-modules (PTA sub-modules), which are commonized so as to allow a universal design, and a display device configured with a plurality of the PTA sub-modules connected to one another. Furthermore, the present invention is intended to provide a new connection structure in which a standard connector with a low withstand voltage can be used for the connection between the PTA sub-modules.
In order to achieve the above-mentioned objects, a PTA sub-module according to a first invention comprises a plasma tube array including a plurality of plasma tubes arranged in parallel on a front-side supporting sheet, and a plurality of display electrode pairs formed, each of which includes a first electrode and a second electrode that extend in the direction crossing each of the plasma tubes, on the front-side supporting sheet wherein the PTA sub-module further comprises connection boards, on each of which a first connector connected to the first electrode and a second connector connected to the second electrode are provided separately in the direction in which display electrodes extend, at both ends of the front-side supporting sheet in the direction in which the display electrodes extend.
In the first invention, the connections between the first electrodes and between the second electrodes of adjacent PTA sub-modules as well as between the first electrodes or the second electrodes and drive circuits become easy. Furthermore, since the connectors that connect the first electrodes and the second electrodes are provided separately, the intervals between adjacent terminals of each connector can be large. Moreover, since adjacent terminals have the same type of electrode potential, it is sufficient for the connectors to have a withstand voltage as low as the scanning voltage. That is, according to the first invention, it is not necessary to alter the arrangement pattern of the display electrodes according to the arrangement of the PTA sub-modules, and the connectors for connecting between the display electrodes as well as the connection boards provided with the connectors can be commonized to have a lower withstand voltage. Accordingly, production costs can be reduced significantly and thus inexpensive display devices can be provided. Furthermore, the PTA sub-modules are flexibly replaceable and therefore the number of maintenance steps also can be reduced.
The term “plasma tube array-type display sub-module (PTA sub-module)” denotes a display component as described above including a plasma tube array in which a display screen of, for example, one meter square is considered as one unit, and it denotes a semifinished product of a display panel that does not include, for example, a power supply circuit. Furthermore, the term “plasma tube array-type display system module (PTA system module)” denotes a system module that composes one display panel with a plurality of PTA sub-modules being connected laterally and/or vertically to one another through, for example, predetermined connectors, and it denotes a system component that composes a display device when, for example, an X drive circuit, a Y drive circuit, an address drive circuit, and a power supply circuit are connected thereto.
A PTA sub-module according to a second invention is characterized in that in the first invention, the both connection boards connected the display electrode pairs are mounted on a rear side of the plasma tube array-type display sub-module, on the connection board provided at one end of the front-side supporting sheet, the first connector is provided in a position further away from the plasma tube located outermost on the side of the one end than the second connector, and on the connection board provided at the other end of the front-side supporting sheet, the first connector is provided in a position further away from the plasma tube located outermost on the side of the other end than the second connector.
In the second invention, the first connector to which the first electrodes are connected is provided always in a position away from the plasma tube located outermost of the PTA sub-module (on the outer side) on the connection boards provided at both ends of the PTA sub-module, while the second connector to which the second electrodes are connected is provided always in a position close to the plasma tube located outermost of the PTA sub-module (on the inner side) on the connection boards provided at both ends of the PTA sub-module. Therefore, when a plurality of PTA sub-modules are to be connected laterally (i.e. a joining direction that intersects the direction in which the plasma tubes extend) to one another, a cable that connects the same type of connectors located on the inner side to each other can be arranged on top of a cable that connects the same type of connectors located on the outer side to each other, reliable connections can be obtained without bending the connection cables, and the gap between adjacent PTA sub-modules can be minimized. Furthermore, even when operations are repeated including, for example, disassembling an assembled PTA system module into a plurality of PTA sub-modules and reconstructing one PTA system module, the first connectors, the second connectors, and the display electrodes do not cause excessive loads, and for example, damage to the first connectors and/or the second connectors, damage to the connection boards, and deformation of the display electrodes, which result from the excessive loads, can be avoided. Thus it is possible to provide high quality display devices with a lower possibility of causing, for example, disconnection.
Furthermore, a PTA sub-module according to a third invention is characterized in that in the second invention, the first electrode is a X electrode that is used as a scanning electrode, the second electrode is an Y electrode that is used as a common electrode, and on each of the connection boards provided at the one end and the other end, the first connector connected to the X electrode is provided in a position further away from the plasma tube located outermost on each of the sides of the one end and the other end than the second connector connected to the Y electrode.
In the third invention, the first electrode is an X electrode that is used as a scanning electrode and the second electrode is a Y electrode that is used as a common electrode, and on each of the connection boards provided at one end and the other end, the first connector connected to the X electrode is provided in a position further away from the plasma tube located outermost than the second connector connected to the Y electrode. Accordingly, the cable for connecting the Y electrodes between the adjacent PTA sub-modules can be short and therefore the line resistance can be reduced.
Furthermore, a PTA sub-module according to a fourth invention is characterized in that in the first invention, the both connection boards connected the display electrode pairs are mounted on a rear side of the plasma tube array-type display sub-module, on the connection board provided at one end of the front-side supporting sheet, the second connector is provided in a position further away from the plasma tube located outermost on the side of the one end than the first connector, and on the connection board provided at the other end of the front-side supporting sheet, the first connector is provided in a position further away from the plasma tube located outermost on the side of the other end than the second connector.
In the fourth invention, the first connectors, to which the first electrodes are connected, are provided on the outer side on the connection board provided at one end of the PTA sub-module and on the inner side on the connection board provided at the other end, and the second connectors, to which the second electrodes are connected, are also provided on the inner side on the connection board provided at one end of the PTA sub-module and on the outer side on the connection board provided at the other end. Therefore, when the PTA sub-modules are to be connected laterally to one another, the cables for connecting the same type of electrodes to each other between adjacent PTA sub-modules connect outer-side connectors to inner-side connectors with respect to both connectors for connecting the X electrodes and those for connecting the Y electrodes. Accordingly, the length of the connection cables can be conformed. Thus, production costs can be reduced further, reliable connections can be obtained without bending the connection cables, and the gap between adjacent PTA sub-modules can be minimized. In this case, the connection boards provided at both left and right ends of the front-side supporting sheet can also be commonized with the same configuration, which can be used at either end by being rotated 180 degrees.
Moreover, a PTA sub-module according to a fifth invention is characterized in that in the fourth invention, the connection board provided at one end of the front-side supporting sheet has the same configuration as that of the connection board provided at the other end, the first electrode and the second electrode arranged alternately are connected to the first connector and the second connector, respectively, on the connection board provided at the one end, and the first electrode and the second electrode are connected to the second connector and the first connector, respectively, on the connection board provided at the other end.
In the fifth invention, the first connection board provided at one end of the front-side supporting sheet has the same configuration as that of the second connection board provided at the other end. On the first connection board, the first electrode and the second electrode that are arranged alternately are connected to the first connector and the second connector, respectively. On the second connection board, the first electrodes and the second electrodes are connected to the second connector and the first connector, respectively. Thus, the connection boards provided at both left and right ends of the front-side supporting sheet can also be commonized with the same configuration, which can be used at either end by being rotated 180 degrees. Moreover, since the number of types of the flexible cables to be connected can be reduced, production costs can be reduced significantly, and thus inexpensive display devices can be provided.
Furthermore, a PTA sub-module according to a sixth invention is characterized in that in any one of the first to fifth inventions, a first wiring conductor that connects the first connector to the first electrode and a second wiring conductor that connects the second connector to the second electrode are provided separately on the front and rear sides of the connection wiring board.
In the sixth invention, the first connector and the second connector are provided separately on one face of a wiring board, and the first wiring conductor that connects the first connector to the first electrodes and the second wiring conductor that connects the second connector to the second electrodes are provided separately on the front and rear sides of the connection wiring board. Accordingly, no short circuit occurs between the first wiring conductor and the second wiring conductor and thereby they can be connected to the two connectors reliably.
Next, in order to achieve the aforementioned objects, a display device according to a seventh invention is characterized in that a plurality of PTA sub-modules according to any one of the first to sixth inventions are arranged in the direction that intersects the direction in which the plasma tubes extend, and a flexible cable connecting between the same type of connectors at adjacent end portions of the adjacent PTA sub-modules.
In the seventh invention, since a plurality of PTA sub-modules with the universal configurations in any one of the first to sixth inventions are connected to one another, it is not necessary to alter the arrangement pattern of the display electrodes according to the arrangement of the PTA sub-modules, and the connectors for connecting between the display electrodes as well as the connection boards provided with the connectors can be commonized. Accordingly, production costs can be reduced significantly and inexpensive large-screen display devices can be provided. Furthermore, the PTA sub-modules are flexibly replaceable and therefore the number of maintenance steps also can be reduced.
As described above, according to the configuration of the present invention, the PTA sub-modules have a universal configuration. Therefore, when a plurality of PTA sub-modules are connected to one another to configure a large screen, it is not necessary to prepare PTA sub-modules with arrangement patterns of the display electrodes altered according to the arrangement thereof, and the connectors for connecting between the display electrodes as well as the connection boards provided with the connectors can be commonized. Accordingly, production costs can be reduced significantly and thereby inexpensive display devices can be provided. Furthermore, since the configuration is employed in which the connectors on the X electrode side and the Y electrode side are separated from each other by using a relay multilayer wiring substrate, the withstand voltage required for the connectors can be lowered significantly. Moreover, the PTA sub-modules can be flexibly replaceable and therefore the number of maintenance steps also can be reduced.
Hereinafter, plasma tube array-type display sub-modules (PTA sub-modules) according to embodiments of the present invention are described in detail with reference to the drawings.
As shown in
The plurality of plasma tubes 31, 31, . . . arranged in parallel are held between a rear-side supporting sheet 33 and a front-side supporting sheet 35. The rear-side supporting sheet 33 comprises address electrodes 32, 32, . . . provided to be in contact with the lower surface in the longitudinal direction of each plasma tube 31. The front-side supporting sheet 35 comprises display electrodes 34, 34, . . . provided in the direction crossing the upper surface in the longitudinal direction of each plasma tube 31. The front-side supporting sheet 35 is a flexible sheet and is configured with, for example, a polycarbonate film or a PET (polyethylene terephthalate) film.
A plurality of display electrodes 34, 34, . . . are arranged in a stripe pattern on the inner surface of the front-side supporting sheet 35. They are in contact with each plasma tube 31 in such a manner as to cross the upper surface thereof. Adjacent display electrodes 34 and 34 configuring a display electrode pair serve as an X electrode and a Y electrode, and a display discharge is generated inside the plasma tubes 31, 31, . . . between the X electrode and the Y electrode. The display electrodes 34 can be formed in an arrangement pattern known in the present field, such as a mesh pattern, a ladder pattern, or a comb teeth pattern, in addition to a stripe pattern. Furthermore, examples of the material that is used for the display electrodes 34 include transparent conductive materials such as ITO (indium tin oxide) and SnO2 and metal conductive materials such as Ag, Au, Al, Cu, and Cr.
Various methods known in the present field can be used for the method of forming the display electrodes 34. For example, they may be formed using a thick-film forming technique such as printing or may be formed using a thin-film forming technique that includes a physical deposition method or a chemical deposition method. One example of the thick-film forming techniques is a screen printing method. Among the thin-film forming techniques, examples of the physical deposition method include a vapor deposition method and a sputtering method. Examples of the chemical deposition method include a thermal CVD method, a photo-CVD method, and a plasma CVD method.
The address electrodes 32, 32, . . . each are provided per plasma tube 31 on the upper surface of the rear-side supporting sheet 33 located on the rear face of the PTA sub-module 30 along the longitudinal direction of the plasma tubes 31, 31, . . . . The address electrodes 32, 32, . . . form light-emitting cells at intersections with the paired display electrodes 34, 34, . . . . The address electrodes 32 also can be formed using various materials and methods that are known in the present field.
In the above-described configuration, when the PTA sub-module 30 serves as one for color display, as shown in
When the conventional PTA sub-modules 1, 1, . . . are to be connected laterally to each other, as described with reference to
However, it is necessary to clearly distinguish the types of the PTA sub-modules 1, 1, . . . to determine their arrangement when a PTA system module 45 for a large screen is to be composed and thereby the work efficiency is decreased. Furthermore, when a failure occurs in any one of the PTA sub-modules 1a, 1b, and 1c, it can be replaced only with the same type of the PTA sub-module 1a, 1b, or 1c. Therefore, the PTA sub-module 1 cannot be used flexibly in any position.
Therefore, in the present invention, all the arrangement patterns of the display electrodes 34, 34, . . . of the PTA sub-modules 30, 30, . . . are commonized, and additionally, relay connection boards provided with two connectors are used, which results in a configuration that allows the PTA sub-modules 30, 30, . . . to be connected flexibly to each other as required without depending on the arrangements of the PTA sub-modules 30.
As described above, the PTA sub-modules 30 of the present invention include display electrodes 34, 34 and 34 comprising the same arrangement pattern despite the arrangement of the PTA sub-modules 30. Furthermore, as described later, each PTA sub-module 30 includes common connection boards 38, with a connector for X electrodes and a connector for Y electrodes provided for each of the left and right terminals of the display electrode 34, and cables 37 connect between the same types of connectors. Thus, one PTA system module 45 for a large screen is composed (see
The connection boards 38 are fixed to both end portions on the rear side of each PTA sub-module 30 and are connected to the display electrodes 34 and 34.
The connection board 38L is mounted at the left end of the rear frame of the PTA sub-module 30 by fixing means 39 such as screws. Similarly, the connection board 38R is mounted at the right end of the rear frame by fixing means 39. On the other hand, in the display electrodes 34, 34, . . . formed on the inner surface of the front-side supporting sheet 35 of the PTA sub-module 30, for example, 16 pairs, that is 32 pieces of X electrodes and Y electrodes are combined to be led out as one group at the left and right terminals. In
Eight pieces of X electrodes 34X, 34X, . . . and eight pieces of Y electrodes 34Y, 34Y, . . . are connected alternately to electrode Nos. 01 to 16 of the input contact points of the connection board 38L. Eight pieces of X electrodes 34X, 34X, . . . and eight pieces of Y electrodes 34Y, 34Y, . . . are connected to odd electrode numbers and even electrode numbers, respectively. The connection board 38L includes a first connector 381 and a second connector 382. Eight pieces of X electrodes 34X, 34X, . . . placed at the odd numbers from the top are combined to be connected to the first connector 381. Eight pieces of Y electrodes 34Y, 34Y, . . . placed at the even numbers from the top are combined to be connected to the second connector 382. The two connectors 381 and 382 are arranged away from each other in the direction in which the display electrodes 34 extend. In
On the other hand, the connection board 38R comprises a configuration obtained by rotating the connection board 38L 180 degrees to reverse the front and rear sides. Eight pieces of X electrodes 34X, 34X, . . . connected to the input contact points of the even electrode numbers are combined to be connected to the first connector 381 of the connection board 38R. Eight pieces of Y electrodes 34Y, 34Y, . . . connected to the input contact points of the odd electrode numbers are combined to be connected to the second connector 382. As in the case of the connection board 38L, the first connector 381 for the X electrodes is located on the inner side of the PTA sub-module 30 (on the side away from the plasma tube 31 located furthest to the right) comparing with the second connector 382 for the Y electrodes.
When the X electrodes 34X, 34X, . . . and the Y electrodes 34Y, 34Y, . . . are combined to be connected in this manner, respectively, connecting pins (not shown in the figures) in the first connectors 381 for the X electrodes and the second connectors 382 for the Y electrodes have the same electrode potentials, respectively. Therefore, the withstand voltage required between the connecting pins can be lowered significantly. Accordingly, inexpensive products with lower withstand voltages can be employed for all the first connectors 381, the second connectors 382, and the cables 37 that connect between the first connectors 381 and 381 and between the second connectors 382 and 382. Consequently, the total cost of the display device can be reduced.
Furthermore, no ground electrodes are arranged on the connection boards 38L and 38R. Therefore, the size of the connection boards 38L and 38R can be reduced and the degree of freedom for arranging the first connectors 381 and the second connectors 382 is improved. This results in various configurations of connections to be made using the cables 37.
On the connection boards 38L and 38R, the input contact points to be connected to eight pieces of X electrodes 34X, 34X, . . . are connected to the first connectors 381 through printed wiring conductors 383, while the input contact points to be connected to eight pieces of Y electrodes 34Y, 34Y, . . . are connected to the second connectors 382 through printed wiring conductors 384. With respect to the X and Y printed wiring conductors 383 and 384, it is preferable that wirings are separated on the front and rear sides of the connection boards 38L and 38R to be multilayered. This is because in that case there is no possibility of causing a short circuit and the size of the connection boards 38L and 38R further can be reduced. When the wirings are to be multilayered, they may be connected to one connector through a through hole as required. That is, the important point is to connect one line of input contact points of the XY electrodes to X-Y separated two lines of connectors on the connection boards 38L and 38R.
In the leftmost PTA sub-module 30 to be connected to the X drive circuit 42, the first connector 381, to which eight pieces of X electrodes 34X, 34X, . . . are combined to be connected, and the X drive circuit 42 are connected to each other with a flexible cable 37Z. In the rightmost PTA sub-module 30 to be connected to a Y drive circuit 43, the second connector 382, to which eight pieces of Y electrodes 34Y, 34Y, . . . are combined to be connected, and the Y drive circuit 43 are connected to each other with a flexible cable 37Z. Therefore, flexible cables to be prepared are three types of cables with different lengths: the flexible cables 37X for connecting between the first connectors 381 and 381, the flexible cables 37Y for connecting between the second connectors 382 and 382, and the flexible cables 37Z for connecting the first connector 381 or the second connector 382 to the X drive circuit 42 or the Y drive circuit 43. In this case, the flexible cables 37Y for connecting Y electrodes to serve as scanning electrodes to each other can be shorter than the cables 37X. The shorter the connection cables, the less the line resistance. Accordingly, the drive pulses can be transmitted effectively.
Naturally, on the connection boards 38L and 38R, the Y electrodes 34Y, 34Y, . . . can be combined to be connected to the first connectors 381 while the X electrodes 34X, 34X, . . . can be combined to be connected to the second connectors 382. In this case, the connection configuration of the PTA sub-modules 30, 30 and 30 is the same as that shown in
Furthermore, in order to commonize ground potential, grounded frames 51 and 53 are provided on the rear face of the X drive circuit 42 or Y drive circuit 43 and on the rear face of the PTA sub-modules 30, respectively. The rear frame 53 of each PTA sub-module 30 comprises a configuration in which, for example, a metal conductor film for grounding is formed on the rear face of a reinforced plastic sheet. The frame 51 and a ground connector 52 also are connected to each other with the ground cable 371, so that the ground potentials of all the PTA sub-modules 30, 30, . . . are commonized and thereby a return path for a discharge current that flows from the X drive circuit 42 and the Y drive circuit 43 through the display electrodes 34, 34, . . . is configured. It is not necessary to provide the ground connectors 52 for grounding on the connection boards 38L and 38R. The ground cables 371 can be connected without regard for the interference with the flexible cables 37X and 37Y.
In
In
The electrode connectors 385, 385 for input mounted on the connection boards 38L and 38R has a construction of the surface mount type connector or insert pin type connector, respectively, and contact points of them are connected to the first and second connector 381, 382 by the multilayered printed wiring. However, the end portions of the display electrodes 34, 34 may be directly connected by, for example, thermal compression method as in the case of
As described above, according to Embodiment 1, it is not necessary to alter the arrangement pattern of the display electrodes 34, 34, . . . according to the arrangement of the PTA sub-modules 30, 30, . . . , and the connectors for connecting between the display electrodes 34 and 34, as well as the connection boards 38 provided with the connectors can be commonized. Therefore, production costs can be reduced significantly and thus inexpensive display devices can be provided. Furthermore, the PTA sub-modules 30, 30, . . . can be flexibly replaceable and therefore the number of maintenance steps also can be reduced.
Moreover, when the PTA sub-modules 30, 30, . . . are to be connected laterally (i.e. a joining direction that intersects the direction in which the plasma tubes 31, 31, . . . extend) to one another, the second connectors 382 and 382 provided on the outer side on the connection boards 38 as well as the first connectors 381 and 381 provided on the inner side on the connection boards 38 are connected to each other with cables 37, respectively. Accordingly, they can be connected to each other reliably without bending the cables 37, and therefore it is possible to minimize the gap between adjacent PTA sub-modules 30 and 30.
Furthermore, even when operations, for example, disassembling the assembled PTA system module 45 into a plurality of PTA sub-modules 30, 30, . . . and reconstructing one PTA system module 45 are repeated, the connectors, the connection boards 38 and the display electrodes 34 are not overloaded, and for example, damage to the connectors and the connection boards as well as deformations of the display electrodes due to overload, can be avoided. Thus it is possible to provide high quality display devices with a lower possibility of causing, for example, disconnection.
Since the configuration of the PTA sub-module 30 that is used for a display device according to Embodiment 2 of the present invention is basically the same as that of Embodiment 1, the same numbers and symbols are used and detailed descriptions are not repeated. As shown in
That is, in Embodiment 2, one type of connection boards 38 is used in common in the left and right terminals of the display electrodes 34. It is configured in such a manner that the connection board 38L and the connection board 38R are the same type of connection boards 38, one of which has been rotated 180 degrees. As a result, the positional relationship between the first connector 381 and the second connector 382 differs when they are viewed from the plasma tube 31 located outermost of the PTA sub-module 30.
The connection board 38L is mounted at the left end of the rear-side frame of the PTA sub-module 30 by fixing means 39 such as screws. Similarly, the connection board 38R is mounted at the right end of the rear frame by the fixing means 39. The connection boards 38L and 38R are arranged so as to be located on the rear face of the PTA sub-module 30. Eight pieces of X electrodes 34X, 34X, . . . and eight pieces of Y electrodes 34Y, 34Y, . . . that are formed on the surface of the PTA sub-module 30 and that are shown representatively are bent toward the rear side together with the front-side supporting sheet 35 at both ends of the PTA sub-module 30 and are connected to the input contact points of the connection boards 38L and 38R, respectively.
Eight pieces of X electrodes 34X, 34X, . . . and eight pieces of Y electrodes 34Y, 34Y, . . . are connected alternately to the electrode Nos. 01 to 16 of the input contact points of the connection board 38L. Eight pieces of X electrodes 34X, 34X, . . . , and eight pieces of Y electrodes 34Y, 34Y, . . . are connected to odd electrode numbers and even electrode numbers, respectively. Furthermore, the connection board 38L includes a first connector 38X and a second connector 38Y. Eight pieces of X electrodes 34X, 34X, . . . placed at the odd numbers from the top are combined to be connected to the first connector 38X. Eight pieces of Y electrodes 34Y, 34Y, . . . placed at the even numbers from the top are combined to be connected to the second connector 38Y. The two connectors 38X and 38Y are arranged away from each other in the direction in which the display electrodes extend. In
On the other hand, the connection board 38R comprises a configuration obtained by rotating the connection board 38L 180 degrees.
Since the electrode Nos. 01 to 16 on the connection boards 38L and 38R remain unchanged, the eight pieces of electrodes 34X, 34X, . . . and eight pieces of Y electrodes 34Y, 34Y, . . . are connected alternately to the electrode Nos. 16 to 01 of the connection board 38R. Eight pieces of X electrodes 34X, 34X, . . . connected to the input contact points of the even electrode numbers are combined to be connected to the first connector 38X of the connection board 38R. Eight pieces of Y electrodes 34Y, 34Y, . . . connected to the input contact points of the odd electrode numbers are combined to be connected to the second connector 38Y. Furthermore, unlike the connection board 38L, the first connector 38X is located on the outer side of the PTA sub-module 30 comparing with the second connector 38Y.
When the X electrodes 34X, 34X, . . . and the Y electrodes 34Y, 34Y, . . . are combined to be connected in this manner, respectively, connecting pins (not shown in the figures) in the first connectors 38X and the second connectors 38Y have the same electrode potentials, respectively. Therefore, the withstand voltage required between the connecting pins can be lowered significantly. Accordingly, inexpensive products with lower withstand voltages can be employed for all the first connectors 38X, the second connectors 38Y, and the cables 37 that connect between the first connectors 38X and 38X and between the second connectors 38Y and 38Y. Consequently, the total cost for the display device can be reduced.
Furthermore, no ground electrodes are arranged on the connection boards 38L and 38R. Therefore, the size of the connection boards 38L and 38R can be reduced and the degree of freedom for arranging of the first connectors 38X and the second connectors 38Y is improved. This results in various configurations of connections to be made using the cables 37.
On the connection boards 38L and 38R, the input contact points to be connected to eight pieces of X electrodes 34X, 34X, . . . are connected to the first connectors 38X through printed wiring conductors 383, while the input contact points to be connected to eight pieces of Y electrodes 34Y, 34Y, . . . are connected to the second connectors 38Y through printed wiring conductors 384. The printed wiring conductors 383 and 384 may be provided with intermediate insulation layer on the same faces of the connection boards 38L and 38R or may be provided separately on the front and rear sides thereof. When they are provided separately on the front and rear sides, there is no possibility of causing a short circuit and the size of the connection boards 38L and 38R further can be reduced.
Furthermore, in the PTA sub-module 30 located on the side that is connected to an X drive circuit, the first connector 38X, to which eight pieces of X electrodes 34X, 34X, . . . are combined to be connected, and the X drive circuit are connected to each other with a flexible cable 37Z. In the PTA sub-module 30 located on the side that is connected to a Y drive circuit, the second connector 38Y, to which eight pieces of Y electrodes 34Y, 34Y, . . . are combined to be connected, and the Y drive circuit are connected to each other with a flexible cable 37Z. Accordingly, with respect to the flexible cables, the flexible cable 37E for connecting between the first connectors 38X and 38X and the flexible cable 37E for connecting between the second connectors 38Y and 38Y are the cables of the same length. Therefore, unlike Embodiment 1, the cables to be prepared are two types of cables with different lengths: the flexible cables 37E and the flexible cables 37Z for connecting to the X drive circuit or the Y drive circuit.
Naturally, on the connection boards 38L and 38R, the Y electrodes 34Y, 34Y, . . . can be combined to be connected to the first connectors 38X while the X electrodes 34X, 34X, . . . can be combined to be connected to the second connectors 38Y. In this case, the connection configuration of the PTA sub-modules 30, 30 and 30 is also the same as that shown in
As described above, according to Embodiment 2, it is not necessary to alter the arrangement pattern of the display electrodes 34, 34, . . . according to the arrangement of the PTA sub-modules 30, 30, . . . , and the connectors, for connecting between the display electrodes 34 and 34, as well as the connection boards provided with the connectors can be commonized. Moreover, the number of the types of the flexible cables can be reduced. Accordingly, production costs can be reduced significantly and thus inexpensive display devices can be provided. Furthermore, the PTA sub-modules 30, 30, . . . can be flexibly replaceable and therefore the number of maintenance steps also can be reduced.
As shown in
As shown in
There is no upper limit in the number of PTA sub-modules 30, 30, . . . to be connected in a matrix, and the number can be increased or reduced flexibly according to the required screen size. It is obvious that, for example, various deformations and substitutions can be made within the spirit of the present invention.
The invention may be embodied in other forms without departing from the spirit or essential characteristics thereof. The embodiments disclosed in this application are to be considered in all respects as illustrative and not limiting. The scope of the invention is indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2009-68099 | Mar 2009 | JP | national |
