JPH0675537A - Driving method for discharge display device - Google Patents

Abstract

PURPOSE:To provide the driving method which makes brightness high by prolonging the discharge time of a display of a discharge display type having trigger electrodes 7. CONSTITUTION:This driving method for the discharge display device having the trigger electrodes 7 consists of the trigger reset to generate a discharge between an anode 3 or cathodes 4 and the trigger electrodes 7 by applying voltages to all the trigger electrodes 7 and to electrify charges on the surfaces of the dielectric layers of all the cells, the dot selection to erase the unnecessary charges of the non-selected cells by impressing the adequate voltages to the anode 3 in the scanning timing of the trigger electrodes 7 and to allow the charges to remain only in the selected sells, the trigger discharge to generate trigger discharge simultaneously in all the selected cells by utilizing the charge, the start of the display discharge by utilizing the charge particles generated in the gas space of the selected cells by the trigger discharge and the simultaneous stop of the discharge of all the cells after the prescribed time. Then, the period when dots are selected by scanning and the period when the selected dots are displayed are independent and, therefore, the longer time of the display discharge is taken within a field and the higher brightness is obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving system for a discharge display device.

[0002]

2. Description of the Related Art FIGS. 6 and 7 show, for example, Japanese Patent Publication No. 3-5037.
FIG. 1 is a partially cutaway perspective view and a cross-sectional view of a discharge display device having a conventionally known trigger electrode shown in Japanese Patent Laid-Open No. 8; This discharge display device comprises a front glass substrate 1, a rear glass substrate 2, and an XY matrix-shaped anode 3 and a cathode 4 sandwiched between them, and each anode 3 is partitioned by a barrier rib 5. On the upper surface of the rear glass substrate 2, below the cathode 4, a trigger electrode 7 is arranged in a direction parallel to the cathode via a dielectric layer 6 and in an intermediate portion between the cathode and the cathode.

FIG. 8 shows, for example, SID 86 DIGES.
6 is a timing chart showing a conventional driving method of a discharge display device having a trigger electrode shown in T., pp391-394 (1986). First, when 110V is applied to all the anodes and -100V is applied to all the trigger electrodes, the voltage difference between the two becomes 210V and discharge occurs. This discharge stops immediately, but the surface of the dielectric layer 6 is positively charged. This is called a trigger set, and this period is called a trigger set period. Next, when 175 V is applied to all the trigger electrodes and the first cathode C1 is set to 0 V, the voltage applied to the trigger electrodes and the positive charge accumulated on the dielectric surface are superposed, and discharge is generated between the cathodes. It happens instantly. This is called trigger discharge. This discharge is immediately stopped, but the gas space along the cathode C1 is filled with charged particles by this discharge, so that the discharge can be performed more easily than other cathodes in which discharge did not occur. When 175V is applied to the anode of the cell to be lit in this state, discharge occurs between the cell and the cathode C1, and only the selected cell is displayed.
In this way, the cathode is scanned similarly to C2, C3 ...

FIG. 9 is a diagram showing a light emission time in a conventional driving method of a discharge type display device having a trigger electrode. One frame time is Tf, the number of scanning lines is L, the number of subfields is N, and the sustain discharge time in the minimum subfield is t _m1 (t
_mN = t _m1 · 2 ^N−1 ) and the trigger set time is t _s , from Tf = N · t _s + L · t _m1 (2 ^N −1), t _m1 = (Tf−N · t _s ) / L · (2 ^N −1). For example, if 1 frame time is 16.6 msec, 500 scanning lines, 256 gradations (N = 8), and the trigger set time is 80 μsec, then t _m1 = 0.125, and the discharge display time for one line per frame is , A maximum of 31.88 μsec, which is only 0.2% of one frame time.

[0005]

In the conventional discharge display type driving method having the trigger electrode as described above, the display discharge can be performed only when the line is scanned. However, there is a problem in that it is difficult to achieve high brightness because only a small amount can be taken.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a driving method capable of achieving high brightness by prolonging the discharge time of display.

[0007]

According to the conventional driving method, 1
A display cell was selected and a display discharge was performed every time line scanning was performed. In this method, within one frame time decided,
There is a limit to how long the display discharge period can be, and the brightness cannot be improved. Therefore, the period for scanning and selecting the display cell is separated from the period for displaying the display cell. The driving method will be described. First, as in the conventional driving method, a voltage is applied to all trigger electrodes to cause discharge between the anodes or cathodes and the trigger electrodes to charge the dielectric layer surfaces of all cells with electric charges. (Trigger Set Period) Next, an appropriate voltage is applied to the anode in synchronization with the scanning timing of the trigger electrode to erase the electric charge of the non-selected cell and leave the electric charge only in the selected cell. (Dot selection period) Next, a trigger discharge is simultaneously generated in all selected cells. (Trigger Discharge) Then, by using the charged particles generated in the gas space of the selected cell by this trigger discharge, the display discharge is started, and after a predetermined time, the discharge is stopped simultaneously for all the cells. (display period)

[0008]

In the present invention, since the scanning period and the display period are independent, it is possible to lengthen the display discharge time in the field.

[0009]

【Example】

Example 1. FIG. 1 is a timing chart showing an embodiment of a driving method according to the present invention. When a voltage Vtr is applied to all the trigger electrodes T ₁ , T ₂ , T ₃ ... Like the conventional driving method, a discharge is generated between the anode and the trigger electrode, and charges are applied to the surfaces of the dielectric layers of all the cells. Accumulated. (Trigger set period) Next, the scanning voltage (Vsf) is applied to the _first trigger electrode T _1.
Is applied, the erase voltage (Ve
When r) is applied, Vsf and the electric charge accumulated on the surface of the dielectric are superposed, and a discharge occurs due to a potential difference between Versf and Ver.
However, Vsf and Ver are individually set to a voltage at which discharge does not occur even if the accumulated charges on the dielectric surface are superposed. This discharge is immediately stopped, and the charged particles generated by the discharge disappear as soon as the next pulse is not applied after the discharge. Therefore, the charges of the non-selected cells on the line L (T ₁ ) are erased, and the charges remain only in the selected cells. Similarly L
(T ₂ ), L (T ₃ ) ... (Dot selection period) Next, when a trigger discharge voltage (Vtd) is applied to the cathode K, Vtd and the electric charge remaining in the dielectric layer of the selected cells are superposed, and all the selected cells simultaneously generate a trigger discharge.
(Trigger Discharge) Then, by using the charged particles generated in the gas space of the selected cell by this trigger discharge, the display discharge is started, and after a predetermined time, the discharge is stopped simultaneously for all the cells. (display period)

FIG. 2 is a diagram showing a light emission time in a driving method according to the present invention for a discharge type display device having a trigger electrode.
One frame time is Tf, the number of scanning lines is L, the number of subfields is N, the erase time is t _e , the sustain discharge time in the minimum subfield is t _m1 (t _mN = t _m1 · 2 ^N-1 ), a trigger set When the time is for _{t s, Tf = N (t} s + L · t e) + t m1 from _{^{(2 N -1), t m1}} = (Tf-N (t s + L · t e)) / (2 N -1 ). For example, assuming that 1 frame time is 16.6 msec, 500 scanning lines, 256 gradations (N = 8), and trigger set time is 80 μsec, the maximum discharge display time for one line per frame is 15960-4000 t.
_e μsec. If the erasing time is 2 μsec, the discharge display time is 7960 μsec, and the ratio to one frame time is 48%.

3 and 4 are cross-sectional views of the display discharge device in which the arrangement of the trigger electrode and the barrier rib is changed to apply the driving method according to the present invention. When the driving method according to the present invention is applied to the conventional structure shown in FIG. 6, a discharge is caused between the charges selectively left during trigger discharge and all the cathodes. The effect of is shown and erroneous discharge easily occurs. Therefore, FIG.
As shown in Fig. 4, the barrier ribs are separated from each other, or as shown in Fig. 4, the arrangement of the trigger electrode is changed from between the cathodes to the lower part of the cathode, and the barrier ribs are separated from each other. did.

Example 2. The driving method according to the present invention can be applied to a display discharge device having an integral common electrode as shown in FIG. 5, in addition to the display discharge device having the trigger electrode used in the first embodiment. In this discharge type display device, a plurality of trigger electrodes 7 arranged in parallel are formed on the upper surface of the rear glass substrate 2 and covered with the dielectric layer 6. Then, the integrated type common cathode 8 is arranged on the upper surface of the dielectric layer 6 at regular intervals, and a plurality of cathodes are arranged in parallel on the upper surface of the dielectric layer 6 so as to be orthogonal to the trigger electrode 7 through the barrier ribs 5 in a grid shape. It consists of three. Similar to the first embodiment, the driving method is a trigger set for supplying electric charges to the dielectric surfaces of all cells by applying a voltage between the trigger electrode and the integral common electrode or anode, and the trigger electrode. The stored charge of the non-selected cells is erased by selectively applying a pulse to the anode so as to cause a slight discharge to the extent that the stored charge of each cell is erased at the timing of the scanning pulse applied to Selective erasing, and a trigger discharge for applying a voltage to the common integrated electrode to generate a discharge in the selected cell by using the charge remaining in the dot selection, and to supply charged particles to the gas space of the selected cell. Using the charged particles generated by the trigger discharge, the display discharge is connected by continuously applying the voltage between the integrated common electrode and the anode.

[0013]

According to the present invention, since the scanning period and the displaying period are independent, it is possible to take a long time for the display discharge within the field, and it is possible to achieve high brightness.

[Brief description of drawings]

FIG. 1 is a timing chart of a driving method of a discharge type display device according to the present invention.

FIG. 2 is a diagram showing a light emission time of a driving method of a discharge type display device according to the present invention.

FIG. 3 is a cross-sectional view of a discharge type display device according to an exemplary embodiment of the present invention.

FIG. 4 is a cross-sectional view of a discharge type display device according to another embodiment of the present invention.

FIG. 5 is a perspective view of a discharge type display device having an integrated electrode according to the present invention.

FIG. 6 is a perspective view of a conventional discharge type display device having a trigger electrode.

FIG. 7 is a cross-sectional view of a conventional discharge type display device having a trigger electrode.

FIG. 8 is a timing chart of a driving method of a conventional discharge type display device having a trigger electrode.

FIG. 9 is a diagram showing a light emission time in a driving method of a conventional discharge type display device having a trigger electrode.

[Explanation of symbols]

 1 Front Glass Substrate 2 Back Glass Substrate 3 Anode 4 Cathode 5 Barrier Rib 6 Dielectric Layer 7 Trigger Electrode 8 Integrated Common Electrode

Front page continuation (72) Inventor Goroku Kobayashi 2-14-40 Ofuna, Kamakura City Mitsubishi Electric Corporation Life Systems Research Institute (72) Inventor Takeo Nishikatsu 2-14-40 Ofuna, Kamakura City Mitsubishi Electric Corporation Life Systems Research Institute (72) Inventor Masao Kano 2-14-40 Ofuna, Kamakura City Mitsubishi Electric Corporation Life Systems Research Institute

Claims (2)

[Claims] 1. A drive of a discharge display device having a discharge electrode pair composed of an anode and a cathode arranged in a matrix shape with a discharge space therebetween, and a trigger electrode arranged with a dielectric layer in parallel with the cathode electrode. In the method, a period for selecting the discharge electrode pair by scanning the trigger electrode and a period for performing display discharge between the anode and the cathode are independent of each other. 2. A method of driving a discharge display device, wherein one of the cathode and the anode is shared.