The present application claims priority from Japanese application JP 2008-057164 filed on Mar. 7, 2008, the content of which is hereby incorporated by reference into this application.
The present invention relates to a plasma display panel (hereafter may also be referred to as PDP), and a plasma display apparatus including a drive apparatus.
In recent years, as a large-size and thin-type color display apparatus, practical application of an alternating current (AC) surface discharge-type PDP has been progressing. Explanation will be given below on embodiments of the AC surface discharge-type PDP which is conventional technology.
The front substrate 21 has a plurality of sustained discharge electrode pairs formed in parallel with a constant distance apart. This sustained discharge electrode pair is configured by an X electrode 22 (hereafter may also be referred to as X), which is a first electrode, and a Y electrode 23 (hereafter may also be referred to as Y), which is a second electrode. The X electrode 22 is configured by an X transparent electrode 22a and an X bus electrode 22b, which aims at compensation of electric conductivity of the transparent electrode. In addition, the Y electrode 23, similarly, is configured by a Y transparent electrode 23a and a Y bus electrode 23b. The X bus electrode 22b and the Y bus electrode 23b are provided extending in a direction of the arrow mark D2 (line direction) in
In
The rear substrate 28 has an address electrode 29 (hereafter referred to simply as an A electrode) which intersects at right angles with the X bus electrode 22b and the Y bus electrode 23b of the front substrate 21, and this A electrode 29 is covered with a dielectric material 30. This A electrode 29 is provided extending in a direction of the arrow mark D1 (row direction) in
It should be noted that in trying to achieve a low power consumption, highly precise and high quality PDP, having brightness and long life assured and enabling stable drive, there is a problem of address discharge characteristics, in particular, address discharge delay. Detail of the address discharge delay will be described later.
Large address discharge delay results in failure in address discharge and makes subsequent sustained discharge impossible, which generates a view screen flicker. Furthermore, drive of a PDP over a prolonged period of time raises also a problem of an increase in address discharge delay (deterioration over time). That is, lighting of a PDP over a prolonged period of time also results in generation of a view screen flicker.
As a method for solving this problem, as shown in JP-A-2002-297091, there has been proposed a PDP with reduced discharge delay, with an electrode arrangement of XYYX-type, and by providing an auxiliary electrode adjacent to the Y electrode, in parallel, on a front plate, and by generation of priming discharge by an in-plane auxiliary electrode at the front plate side. In addition, as shown in JP-A-2003-217458, there has been proposed a PDP with electrode arrangement of XYYX-type for achieving enhancement of emission efficiency in the first discharge region and enhancement of address discharge characteristics in the second region at the same time, and by providing the first discharge region for executing sustained discharge, the second discharge region for executing address discharge, and a gap part connecting both discharge regions, and by execution of address discharge between the Y bus electrode and the address electrode, in the second discharge region partitioned by “rib extending in a row direction and in a line direction”.
However, the PDP shown in JP-A-2002-297091, because it uses an auxiliary electrode, requires an auxiliary electrode material and a member such as a drive circuit for applying voltage to the auxiliary electrode, which results in to increase production cost of the PDP.
In a PDP shown in JP-A-2003-217458, there is no increase in a member like one shown in JP-A-2002-297091, however, because the second discharge region is partitioned in a way to respond to the first discharge region one by one, by “ribs extending in a row direction and in a line direction”, a problem is raised in the case where scanning line number increases by making a PDP with higher precision. That is, narrowing each discharge space of the first discharge region for execution of sustained discharge, in response to higher precision, provides difficulty in securing brightness. Alternatively, narrowing of discharge space of the second discharge region results in an elevation of discharge initiation voltage or an increase in discharge delay, and makes it difficult to stabilize the address characteristics.
The present invention has been proposed in view of the above circumstance, and it is an object of the present invention to provide a PDP having stable address discharge characteristics, even in making higher precision.
Explanation will be given on outline of typical ones among the present invention disclosed in the present specification, as follows.
(1) A plasma display apparatus including at least:
a front substrate; a plurality of first electrodes and second electrodes extending in a line direction, in which each two thereof are arranged alternately in a row direction on the front substrate; a dielectric layer covering the first electrode and the second electrode; a back substrate; a plurality of address electrodes extending in the row direction, which are arranged on the back substrate in the line direction opposed to the first electrode and the second electrode; a plurality of first longitudinal ribs extending in the row direction; a plurality of traverse ribs extending in the line direction; a plurality of display discharge cells formed by the first longitudinal ribs and the traverse ribs; a priming discharge region formed between the traverse ribs of the adjacent display discharge cells of the second electrode, among the display discharge cells adjacent in the row direction; a second longitudinal rib extending in the row direction on an extended line of the first longitudinal rib and partitioning the priming discharge region; a third longitudinal rib extending in the row direction and further partitioning between the second longitudinal ribs into two sections; a priming discharge cell formed by the second longitudinal ribs, the third longitudinal ribs and the traverse ribs; and a convex electrode extended from the adjacent two second electrodes to the each separate priming discharge cell, on the side facing each other of the two second electrodes adjacent in the row direction; wherein there is a gap spatially connecting the display discharge cell and the priming discharge cell, between the front substrate and the traverse rib partitioning the display discharge cell and the priming discharge cell, and a sum of a width in the line direction of a region formed by the second longitudinal ribs and the traverse ribs, and a pattern width of the second longitudinal ribs, is larger than a sum of a width in the row direction of a region formed by the second longitudinal ribs and the traverse ribs, and a pattern width of the traverse ribs.
(2) A plasma display apparatus including at least:
a front substrate; a plurality of first electrodes and second electrodes extending in a line direction, in which each two thereof are arranged alternately in a row direction on the front substrate; a dielectric layer covering the first electrode and the second electrode; a back substrate; a plurality of address electrodes extending in the row direction, which are arranged on the back substrate in the line direction opposed to the first electrode and the second electrode; a plurality of first longitudinal ribs extending in the row direction; a plurality of traverse ribs extending in the line direction; a plurality of display discharge cells formed by the first longitudinal ribs and the traverse ribs; a priming discharge region formed between the traverse ribs of the adjacent display discharge cells of the second electrode, among the display discharge cells adjacent in the row direction; a second longitudinal rib extending in the row direction and partitioning the priming discharge region; a priming discharge cell formed by the second longitudinal ribs and the traverse ribs; and a convex electrode extended from the adjacent two second electrodes to the each separate priming discharge cell, on the side facing each other of the two second electrodes adjacent in the row direction; wherein there is a gap spatially connecting the display discharge cell and the priming discharge cell, between the front substrate and the traverse rib partitioning the display discharge cell and the priming discharge cell, and the second longitudinal ribs are not present on an extended line of the first longitudinal ribs.
(3) A plasma display apparatus including at least:
a front substrate; a plurality of first electrodes and second electrodes extending in a line direction, in which each two thereof are arranged alternately in a row direction on the front substrate; a dielectric layer covering the first electrode and the second electrode; a back substrate; a plurality of address electrodes extending in the row direction, which are arranged on the back substrate in the line direction opposed to the first electrode and the second electrode; a plurality of first longitudinal ribs extending in the row direction; a plurality of traverse ribs extending in the line direction; a plurality of display discharge cells formed by the first longitudinal ribs and the traverse ribs; a priming discharge region formed between the traverse ribs of the adjacent display discharge cells of the second electrode, among the display discharge cells adjacent in the row direction; a rib for the priming discharge region, which connects an intersection of the first longitudinal rib and the traverse rib on the priming discharge region side in one the display discharge cell among the display discharge cells sandwiching the priming discharge region and adjacent in the row direction, and an intersection of the first longitudinal rib and the traverse rib on the priming discharge region side in the other the display discharge cell, and extends in a direction different from on the extended line of the first longitudinal rib, and partitions the priming discharge region; a priming discharge cell formed by the rib for priming discharge region and the traverse rib; and a convex electrode extended from the adjacent two second electrodes to the each separate priming discharge cell, on the side facing each other of the two second electrodes adjacent in the row direction; wherein there is a gap spatially connecting the display discharge cell and the priming discharge cell, between the front substrate and the traverse rib partitioning the display discharge cell and the priming discharge cell.
According to application of the present invention, address discharge can be generated stably by priming discharge, even in making higher precision. Therefore, the present invention can provide a low power consumption, highly precise and high quality PDP, having brightness and long life assured and enabling stable drive.
Other objects, features and advantages of the invention will become apparent from the following description of the embodiments of the invention taken in conjunction with the accompanying drawings.
Explanation will be given below in detail on embodiments of the present invention, with reference to drawings. It should be noted that in all drawings for explaining the embodiments, those having the same function have the same reference numeral, to avoid repeated explanation. In addition, also to those having the same function as elements in a conventional embodiment shown in
First, by using
The proof is as follows. It should be noted that
In addition, in the case of division with a rib extending in a row direction, in
In addition, in the case of division with a rib extending in a line direction, in
First, the case of division with a rib extending in a row direction will be considered. In this case, from
On the other hand, in the case of division of a region with a rib extending in a line direction will be considered. In this case, from
As a result, it is given:
2×S(1)−2×S(2)=d×(H−V) (3)
Therefore, from the equation (3), division by a rib extending in a row direction is better than division by a rib extending in a line direction, when [1] H>V. Furthermore, it is understood that division by a rib extending in a line direction is better than division by a rib extending in a row direction, when [2] H<V″. As described above, the above proposition has been proved. In addition, it is understood that the above proposition is established irrespective of value of the minimal fabrication dimension width d.
The present proposition will be used in embodiments to be described later, as a basis to show that discharge space can be formed efficiently by partitioning a predetermined space region in a row direction.
When discharge space can be formed widely, the elevation of discharge initiation voltage or the increase in discharge delay can be prevented, and the discharge can be stabilized.
Explanation will be given next on the address discharge delay and deterioration over time of the address discharge delay, which can be improved by the present invention. The address discharge delay td is an average period from time when voltage of discharge initiation or higher is applied between electrodes, to time when discharge is formed. In addition, the address discharge delay td is divided into a formation delay tf and a statistic delay ts, and defined as follows:
t
d
=t
f
+t
s (4)
wherein, the formation delay tf is a period from time when seed electrons, which is the start point of discharge, are generated, to time when discharge is formed; the statistic delay ts is an average period from time when voltage of discharge initiation or higher is applied between the electrodes, to time when the seed electrons are generated. The reason for describing as “average” is that, even when measurements of the period till seed electrons are generated are repeated under the same condition, there exist fluctuation and distribution. The formation delay tf and the statistic delay ts are variables necessary to understand the discharge delay phenomenon.
Here, when ta stands for a width of voltage pulse applied to the address electrode, and when the discharges in a plurality of measurements are not generated all within a time of ta, the address discharge becomes failure, and a display flicker is generated, therefore it is necessary that all discharges occur within the address pulse.
Furthermore, in a life test where a PDP is continuously driven and lightened, the address discharge delay, in particular, the statistic delay largely increases. As a result, all discharges do not fall within the address pulse, generating the display flicker. As described above, the statistic delay is an average period from time when voltage of discharge initiation voltage or higher is applied between the electrodes, to time when the seed electrons are generated. The seed electrons, which are discharge seeds, are generated by that electrons which were captured at trap levels present at places a little lower from the conduction band between the valence band and the conduction band in MgO, are emitted into the discharge space by electric field effect or an Auger process. The electron trapping to the trap levels is executed by irradiation of vacuum ultraviolet rays to MgO, or collision of charged particles to MgO, due to the discharge before the address discharge. Here, because the discharge intensity changes little even after continuous lighting, it is understood that the energy intensity of the vacuum ultraviolet rays or charged particles for capturing electrons at the trap levels, is not necessarily reduced. That is, the reason for the reduction of the number of seed electrons discharged to the discharge space is because of reduction of the number of the trap levels themselves. From the above, it is understood that the reason for the increase in the statistic delay by the life test is the reduction of the number of the trap levels in MgO, and the reduction of the number of seed electrons discharged from MgO.
Then, factors inducing the reduction of the number of the trap levels in MgO were investigated.
It should be noted that the above discussion was described in the case where a protective film of the front plate dielectric material is MgO. However, because the protective film in a PDP is under environment always receiving the sputter by ions, it is also the case where the protective film is not MgO.
As shown in
The front substrate 21 has a plurality of sustained discharge electrode pairs formed in parallel, with a constant distance apart. This plural sustained discharge electrode pair is configured by an X electrode 22 (hereafter may also be referred to as X), which is a first electrode, and a Y electrode 23 (hereafter may also be referred to as Y), which is a second electrode. The X electrode 22 is configured by the X transparent electrode 22a having T-character shape, and the X bus electrode 22b aiming at compensating the electric conductivity of the transparent electrode. In addition, the Y electrode 23 is configured by the Y transparent electrode 23a having T-character shape, the Y bus electrode 23b aiming at compensating the electric conductivity of the transparent electrode, and a Y convex electrode 23c. Explanation will be given later on detailed configuration of the Y convex electrode 23c. The X electrode 22 and the Y electrode 23 are provided extending in a line direction. In
In addition, the X electrode 22 and the Y electrode 23 are covered with the dielectric layer 26 composed of a low melting point glass layer, and this dielectric layer 26 is covered with the protective film 27 composed of MgO.
The rear substrate 28 has an address electrode (hereafter referred to simply as an A electrode) 29, which intersects at right angles with the X electrode 22 and the Y electrode 23 of the front substrate 21, and this A electrode 29 is covered with a dielectric material 30. This A electrode 29 is provided extending in the row direction.
On the dielectric material 30, a rib 31 is provided to prevent spread of discharge (to specify a discharge region). On the dielectric material 30, a display discharge cell DDC having the X electrode 22, the Y electrode 23 and the A electrode 29, along with a priming discharge cell PDC having the Y convex electrode 23c and the A electrode 29, are formed by this rib 31. The rib 31 is configured by the first longitudinal rib 31L1 partitioning the display discharge cell DDC by each row, the traverse rib 31T partitioning the display discharge cell by each line, the second longitudinal rib 31L2 partitioning the priming discharge cell PDC, and extending in the row direction on an extension line of the first longitudinal rib 31L1 partitioning the display discharge cell DDC, and the third longitudinal rib 31L3 partitioning the priming discharge cell PDC, and extending in the row direction, not on an extension line of the first longitudinal rib 31L1. It should be noted that the third longitudinal rib 31L3 was arranged so as to be positioned at right the center of the adjacent second longitudinal ribs 31L2 themselves. Therefore, the priming discharge cell PDC is formed by the traverse rib 31T, the second longitudinal rib 31L2 and the third longitudinal rib 31L3. A part between the display discharge cell DDCs themselves arranged in the row direction, sandwiched by the traverse rib 31T, is a priming discharge region 39. In addition, an intersection part of ribs is a common part.
Furthermore, in a region partitioning the display discharge cell DDC and the priming discharge cell PDC, a gap part 35 is formed to spatially connect the display discharge cell DDC and the priming discharge cell PDC. This gap part 35 can be formed by opening a hole into the dielectric material 26 or the protective film 27 at the front substrate 21 side. In the first embodiment, the gap part 35 was formed by altering the height of a rib in a region partitioning the display discharge cell DDC and the priming discharge cell PDC, and that in other regions.
Then, explanation will be given on the configuration of the Y convex electrode 23c described above. The Y convex electrode 23c is extended from the adjacent Y electrode 23 to the separate priming discharge cell PDC partitioned each by a rib, on the facing sides of two adjacent Y electrodes 23 in the row direction each other. It should be noted that the Y convex electrode 23c, in
In addition, the A electrode 29, in the priming discharge region 39, the width in the line direction thereof is designed larger than that in other regions. The other regions mean, for example, parts facing to the X electrode or the Y electrode in the display discharge cell. In this way, a part of an electric field created by the A electrode 29 can compensate a part shielded by the third longitudinal rib 31L3, and the generation of discharge is made easily between the Y convex electrode 23c and the A electrode 29 (it should be noted that the shape of the A electrode in the priming discharge cell PDC is similar as in the second embodiment shown in
Here, in
Therefore, according to the proposition proved above, by partitioning this space region 70 with the third longitudinal rib 31L3 extending in the row direction, a discharge space of the priming discharge cell PDC can be secured efficiently, more stable priming discharge can be executed as compared with a conventional embodiment partitioning with a rib extending in the line direction, and even in making high precision in the row direction (increasing number of the Y electrode 23 for scanning), a PDP excellent in address discharge characteristics can be obtained. In addition, in the case where the width in the row direction of the display discharge cell DDC is required to increase in order to enhance the emission efficiency, reduction of the discharge space in the priming discharge cell PDC can be suppressed, as compared with the case of partitioning in the line direction.
In addition, as shown in
Explanation will be given in detail next on the drive in the present PDP.
First, in all of the display discharge cells DDCs and all of the priming discharge cells PDCs, by reset the discharge in the reset period, rib charge is formed on the surface of the protective film 27 on the front plate 36 side, and on the surface of the dielectric material 30 and the fluorescent material layer 32 of the rear plate 37.
Explanation will be given next on the operation during the address discharge period. The Y electrode 23 passing the A line in
When a scanning pulse is applied to the Yi electrode, and an address voltage pulse is applied to the A electrode 29, and after elapsing by a certain discharge delay time, in the display discharge cell DDC containing the Yi electrode (in particular, the Y transparent electrode 23a) and the A electrode 29, address discharge is generated. On the other hand, when a scanning pulse is applied to the Yi electrode, and an address voltage pulse is applied to the A electrode 29, or after elapsing by a certain discharge delay time, in the priming discharge cell PDC containing the Yi electrode (in particular, the Y convex electrode 23c) and the A electrode 29, priming discharge is generated.
In the case where an address discharge in the display discharge cell DDC is generated first, a usual address discharge is generated similarly as in a conventional embodiment. On the other hand, in the case where a priming discharge in the priming discharge cell PDC is generated first, formation of the address discharge in the display discharge cell DDC is promoted, because charged particles such as positive ions or electrons generated by this priming discharge flow into the display discharge cell DDC, which is spatially connected with the priming discharge cell PDC through the gap part 35. That is, in the case where the discharge delay time of the address discharge itself is large, the discharge delay time of the address discharge can be restricted by generation of the priming discharge. This effect can suppress particularly deterioration over time of the address discharge delay (to be described later).
Subsequently, when a scanning pulse is applied to the Y(i+1) electrode, and an address voltage pulse is applied to the A electrode 29, and after elapsing by a certain discharge delay time, in the display discharge cell DDC containing the Y(i+1) electrode (in particular, the Y transparent electrode 23a) and the A electrode, an address discharge is generated. On the other hand, when a scanning pulse is applied to the Y(i+1) electrode, and an address voltage pulse is applied to the A electrode 29, or after elapsing by a certain discharge delay time, in the priming discharge cell PDC containing the Y(i+1) electrode (in particular, the Y convex electrode 23c) and the A electrode, a priming discharge is generated.
In addition, similarly in the case when the i-th scanning pulse is applied, the discharge delay time of the address discharge can be restricted by generation of the priming discharge.
Here, it never happens that the priming discharge in the priming discharge cell PDC, which is configured by the Yi electrode and the A electrode 29, disturbs the charge state of rib (this is referred to hereafter as “interference of scanning” in the present specification) formed during the reset period, in the priming discharge cell PDC which is configured by the Y(i+1) electrode and the A electrode 29. It is because the Y convex electrode 23c of the Yi electrode is not extended to the priming discharge cell PDC configured by the Y(i+1) electrode and the A electrode 29, and also each priming discharge cell PDC is partitioned by the second longitudinal rib 31L2 and the third longitudinal rib 31L3. Therefore, while taking the XYYX arrangement, the priming discharge cell PDC can be configured (in the sense that interference of scanning can be prevented).
The charges generated by the address discharge in the address discharge period are formed on the surface of the dielectric layer 26 and the protective film 27 covering the Y electrode 23.
After this address discharge period, in the sustained discharge period, a voltage pulse is applied between the X electrode 22 and the Y electrode 23 alternately to generate a sustained discharge between the X electrode 22 and the Y electrode 23. Ultraviolet rays from plasma generated by this sustained discharge excite the fluorescent material layers 32 for red, green and blue lights, by which visible emission is obtained, and a display view screen is configured by emission from each of the discharge cells DDCs.
In this time, because the gap part 35 is designed narrow, the sustained discharge seldom spreads to the priming discharge cell PDC. Accordingly, as compared with the protective film 27 inside the display discharge cell, which directly receives sputtering by charged particles, the protective film 27 on the priming discharge cell PDC has smaller sputtered amount in the sustained discharge. Therefore, deteriorated amount of address discharge characteristics (for example, seed electron discharge performance having influence on the display delay time) in the priming discharge cell PDC is extremely small. From the above reason, the present PDP is particularly effective to the problem of deterioration over time, that is, increase in the address discharge delay, caused by the drive of a PDP over a prolonged period of time.
A 42-type PDP having a cell structure shown in
In the three kinds of proto-type PDPs of “reference”, “line partitioning type” and “row partitioning type”, the size of the display discharge cell is the same. In addition, the present proto-type PDPs were prepared to satisfy H>V, by using H and V in the above proposition. As a result, the priming discharge cell of the “row partitioning type” was capable of securing the area 1.25 times the area of the priming discharge cell of the “line partitioning type”. Evaluation results of the address discharge delay td of PDPs prepared in the present experiment are shown in
From the experimental results shown in
A PDP in this second embodiment has configuration where the second longitudinal rib 31L2 is removed in the priming discharge region 39 arranged with the second longitudinal rib 31L2 and the third longitudinal rib 31L3 in the first embodiment above. That is, two adjacent priming discharge cells PDCs, sandwiching the second longitudinal rib 31L2 in the first embodiment, are combined to achieve single priming discharge cell PDC.
By taking such a configuration, space per priming discharge cell PDC can be broadened. Therefore, because the ratio of suppression of discharge formation caused by collision of charged particles generated at the discharge formation to the rib wall surface, can be reduced, the address discharge characteristics can be enhanced further, as compared with the first embodiment. In addition, the advantage includes reduction of parts number, corresponding to the elimination of the second longitudinal rib 31L2, as compared with the first embodiment. Furthermore the advantages include enabling reduction of electrostatic capacitance between the electrodes, reduction of useless power consumption, and enhancement of the response of drive control, by replacing general low melting point glass as a rib material with discharge gas having low dielectric constant.
Here, in
Other configurations and drive motion are similar as in the PDP shown in the first embodiment described above.
A PDP in this third embodiment has a configuration where a declined rib 31D is arranged, so as to alternately connect each of an intersection of the first longitudinal rib 31L1 and the traverse rib 31T on the A line, and an intersection of the first longitudinal rib 31L1 and the traverse rib 31T on the A′ line, by elimination of the second longitudinal rib 31L2 and the third longitudinal rib 31L3 in the priming discharge region 39, wherein the second longitudinal rib 31L2 and the third longitudinal rib 31L3 were arranged in the first embodiment above. In addition by elimination of the second longitudinal rib 31L2, there are present two display discharge cells connected via the gap part 35 with single priming discharge cell PDC.
By taking such a configuration, space per priming discharge cell PDC can be broadened. Therefore, the ratio of the suppression of discharge formation caused by collision of charged particles generated at the discharge formation to the rib wall surface, can be reduced. Because the gap part 35 can take wide space in the line direction and charged particles can travel to the display discharge cell DDC more efficiently as compared with the first and the second embodiments, the address discharge delay can be reduced.
Other configurations and the drive operation are similar as in the PDP shown in the first embodiment described above.
A PDP in this fourth embodiment is designed such that a T-character shaped part of the X transparent electrode 22a and a T-character shaped part of the Y transparent electrode 23a, which were designed to have the same shape and the same area in the first embodiment above, have an effective ratio of electrode areas thereof of 1:2. Here, the effective electrode area in the present specification is defined as “electrode area within a range contained in the display discharge cell DDC”.
In the first embodiment, the priming discharge cell PDC has wide space and the X electrode is standardized to the one by the display discharge cell DDC adjacent in the row direction. Because of the influence of these, as compared with a configuration of a conventional embodiment, the position of an average visible emission center in the sustained discharge comes nearer to the X electrode 22 side than the Y electrode 23 side. In this case, there is risk to generate an adverse effect on the display quality of a PDP.
Explanation will be given next on this adverse effect with reference to drawings.
Therefore, by taking such a configuration as in the fourth embodiment, the average emission center in the sustained discharge can be displaced to the Y electrode 23 side having large electrode area, and can prevent the deterioration of display quality.
In addition, because the area of the T-character shaped part in the Y transparent electrode 23a becomes large, an effective region where voltage is applied is extended, and the address discharge characteristics in the display discharge cell DDC can be improved.
Here, in the first embodiment, the Y convex electrode 23c, when viewed in the line direction, is arranged in - - - A-A′-A′-A-A-A′-A′-A-A - - - , however, as in the fourth embodiment, it may be arranged - - - A-A′-A-A′-A-A′-A-A′-A - - - . It should be noted that “A” here means that the Y convex electrode 23c protrudes from the Y electrode 23 on the A line side, and “A′” means that the Y convex electrode 23c protrudes from the Y electrode 23 on the A′ line side.
Other configurations and the drive operation are similar as in the PDP shown in the first embodiment described above.
A PDP in this fifth embodiment is provided with a height adjustment layer 71 in a region where the priming discharge cell PDC is present, on the protective film 27 in the front plate 36 (a side with the discharge space 33), in the first embodiment above. In addition, on the height adjustment layer 71, an electron discharge layer 72 is provided.
By taking such a configuration, as compared with the first embodiment, a distance of discharge space between the Y convex electrode 23c and the A electrode 29 in the priming discharge cell PDC can be shortened effectively, discharge initiation voltage of priming discharge can be lowered, or discharge delay time of priming discharge can be shortened. In addition, by the electron discharge layer 72, the discharge initiation voltage of priming discharge can be lowered further, or the discharge delay time of priming discharge can be shortened further.
Furthermore, according to the present configuration, because wider discharge space can be secured, formation of the height adjustment layer 71 and the electron discharge layer 72 becomes easy. In addition, as for the electron discharge layer 72, because wider discharge space can be secured, effect of the electron discharge can be enhanced. The reason is considered that with the increase in the area of the surface facing to discharge gas among the electron discharge layer, the number of effective atoms and trap levels, which becomes electron discharge sources, is increased.
The height adjustment layer 71 is provided mainly aiming at shortening the distance of the discharge space, and a material thereof is not especially limited, however, it is formed by using, for example, a dielectric material of the same kind as the dielectric layer 26. General glass materials (relative dielectric constant=3 to 10) may be used. In addition, because a material with the higher relative dielectric constant can suppress the voltage drop by the height adjustment layer 71, a material with high relative dielectric constant such as TiO2 (relative dielectric constant=approximately 100) may be used.
As the electron discharge layer 72, it is preferable to use a material having a high secondary electron discharge coefficient, or a material having a small value of work function. For example, an oxide of an alkali metal, an oxide of an alkaline earth metal (for example, BaO, SrO, CaO or the like), a rare earth oxide, a fluoride or the like is included.
It should be noted that the height adjustment layer 71 is arranged on the protective film 27 (on the side with discharge space 33) in
Other configurations and the drive operation are similar as in the PDP shown in the first embodiment described above.
A PDP in this sixth embodiment is provided with a height adjustment layer 71 in a region where the priming discharge cell PDC is present, on the dielectric layer 30 in the rear plate 37 (a side with the discharge space 33), in the first embodiment above. In addition, on the height adjustment layer 71, an electron discharge layer 72 is provided.
By taking such a configuration, as compared with the first embodiment, the distance of the discharge space between the Y convex electrode 23c and the A electrode 29, in the priming discharge cell PDC, can be shortened effectively, the discharge initiation voltage of priming discharge can be lowered, or the discharge delay time of priming discharge can be shortened. In addition, by the electron discharge layer 72, the discharge initiation voltage of the priming discharge can be lowered further, or the discharge delay time of the priming discharge can be shortened further.
Furthermore, according to the present configuration, because wider discharge space can be secured, formation of the height adjustment layer 71 and the electron discharge layer 72 becomes easy. In addition, as for the electron discharge layer 72, because wider discharge space can be secured, effect of the electron discharge can be enhanced. The reason is considered that with the increase in the area of the surface facing to discharge gas in the electron discharge layer, the number of effective atoms and trap levels, which are electron discharge sources, is increased.
The height adjustment layer 71 is provided mainly aiming at shortening the distance of the discharge space, and a material thereof is not especially limited, however, it is formed by using, for example, a dielectric material of the same kind as the dielectric layer 30. In addition, use of the rib 31 makes it possible to form the height adjustment layer 71 in the same step as a process for forming the rib. General glass materials (relative dielectric constant=3 to 10) may be used. In addition, because a material with the higher relative dielectric constant can suppress the voltage drop by the height adjustment layer 71, a material with high relative dielectric constant such as TiO2 (relative dielectric constant=approximately 100) may be used.
As the electron discharge layer 72, it is preferable to use a material having high secondary electron discharge coefficient, or a material having small value of work function. For example, an oxide of an alkali metal, an oxide of an alkaline earth metal (for example, BaO, SrO, CaO or the like), a rare earth oxide, a fluoride or the like is included.
It should be noted that the height adjustment layer 71 is arranged on the dielectric layer 30 (on the side with discharge space 33), in
Other configurations and the drive operation are similar as in the PDP shown in the first embodiment described above.
A PDP in this seventh embodiment is designed to have two X electrodes, which was designed to be single by electric connection in the first embodiment above. By taking such a configuration, it becomes possible to apply different voltage waveform to each of X electrodes.
In addition, a region without a rib (the inter-line region 34) sandwiched by the traverse rib 31T was provided in a region between each of the display discharge cells DDCs adjacent in the row direction. By taking such a configuration, it becomes possible to enhance exhaustion efficiency in an exhaustion process, by utilizing a region where the traverse rib 31T under the X electrode was present as an exhaustion path.
Furthermore, the X bus electrode 22b and the Y bus electrode 23b are arranged in a region sandwiching the display discharge cell DDC, not in a region facing to the A electrode sandwiching the traverse rib 31T. By taking such a configuration, it becomes possible to make apart distance between the Y bus electrode 23b and the priming discharge cell PDC, and therefore, influence of displacement in the up and down directions in laminating the front plate 36 and the rear plate 37 can be mitigated. The influence by displacement means scanning interference generated in an arrangement where the Y bus electrode 23b faces to the A electrode 29, sandwiching the priming discharge cell PDC, as described, for example, in the first embodiment.
Other configurations and drive motion are similar as in the PDP shown in the first embodiment described above.
It should be further understood by those skilled in the art that although the foregoing description has been made on embodiments of the invention, the invention is not limited thereto and various changes and modifications may be made without departing from the spirit of the invention and the scope of the appended claims.
Number | Date | Country | Kind |
---|---|---|---|
2008-057164 | Mar 2008 | JP | national |