JPH01266594A - Display device - Google Patents

Abstract

PURPOSE:To reduce power consumption by limiting row electrodes which are scanned when only some of row electrodes are used to only required row electrodes. CONSTITUTION:Row electrodes 21-2n/2 (n: even number) are scanned sequentially as well as a conventional driving method. Then if the number of scanned row electrodes counted by a counter incorporated in an enable pulse generating circuit 18 exceeds a row electrode number n/2 set by a row electrode setting circuit 17 at the end of the scanning of the row electrode 2n/2, the enable pulse generating circuit 18 outputs an enable pulse 20 and all outputs of a decoder 12 are unselected. Consequently, outputs of a row driver are also all unselected, so none of the row electrodes is scanned. Namely, while the enable pulse 20 is outputted, a display element 1 is not driven. Consequently, the power consumption of the display element is reducible.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a display device, and in particular, the present invention relates to a display device, and in particular, the present invention relates to a display device that emits light at the intersection of selected row and row electrodes from a group of rows and rows arranged in a matrix in the row and row direction and facing each other. Regarding plasma display.

[Conventional technology]

In this type of plasma display (hereinafter abbreviated as display), a plurality of generally transparent column electrode groups parallel to each other and a plurality of mutually parallel generally opaque row electrode groups are arranged in a matrix, and the picture electrodes A method is generally known in which an ionizable gas is interposed between the groups and the intersection of a selected row electrode and a selected column electrode is displayed by discharge light emission. - In the above display, an optical image corresponding to the input signal can be displayed by controlling the electrode selection method of the row electrode group and the column electrode group in accordance with the input signal. For example, one of the row electrode groups and the column electrode groups, for example, each electrode of the row electrode group, is sequentially selectively scanned in a time-division manner, and the other electrode group, for example, each electrode of the column electrode group, is selectively scanned. By selectively controlling the input signal while maintaining synchronization with scanning, an optical image corresponding to the input signal can be displayed on the display panel surface. External electrode type display panels need to be driven by AC voltage, and drive signals applied to row electrode groups and column electrode groups include high-frequency discharge pulses called toggle pulses.

FIG. 2 is a block diagram of a conventional display device. The display element 1 shown in FIG. 2 consists of mutually parallel row electrodes 2 (hereinafter, unless a specific one is indicated, suffixes will be omitted) and mutually parallel column electrodes 3 orthogonal to each other. It has a display cell 4. Furthermore, each of the row electrodes 2 is correspondingly connected to a respective output terminal of a row driver 5 , and each electrode of the column electrodes 3 is correspondingly connected to a respective output terminal of a column driver 6 . A discharge pulse 7 necessary for discharging the display element 1 is connected to the input of each row and column driver 5.6. - On the other hand, the clock pulse 8 for controlling the timing at which the row and column electrodes 2.3 are selected is connected together with the input data 10 to the input of the data control section 9, and the output of the data control section 9 is connected to the input of the column driver 6. It is connected. Further, the clock pulse 8 is input to a counter 11, the output of which is connected to the input of a decoder 12, and the output is further connected to the input of the row driver 5.

Next, the principle of operation of the display device shown in FIG. 2 will be described.

The clock pulse 8 is counted down in the counter 11 by an amount equal to the number n of row electrodes 2 to be driven, and then decoded in the decoder 12, and the output is a scanning pulse with a pulse width t (clock pulse period) and a period nt. resulting in pulse 13. Each scanning pulse 131, 132・
...13n are each shifted in phase by pulse width t, and scanning pulse 131.1 is generated for each input of clock pulse 8.
32...13n sequentially generate outputs. The scanning pulse 13 is mixed with the discharge pulse 7 and input to the row driver 5, where it is stepped up to the voltage required for discharge to generate the row drive signal 16 and the corresponding row electrodes 21, 22, .
...2n are sequentially driven.

On the other hand, the input data 10 corresponds to the scanning of the row electrodes 2.
Each time a clock pulse 8 is input, it is input to a data control unit 9, where it is arranged to become a signal to a corresponding column electrode, and its output is input to a column driver 6 to generate a discharge pulse 7.
and then stepped up to the voltage required for discharge to produce a column drive signal 14 for the corresponding column electrode 3.
to drive. The discharge pulse in the column drive signal 14 and the discharge pulse in the row drive signal 16 are in opposite phase to each other,
In the display cell 4 at the intersection of the selected row and column electrodes 2 and 3,
The column drive signal 14 and the row drive signal 16 are added together, and the voltage becomes higher than the discharge start voltage, causing discharge and light emission.

[Problem to be solved by the invention]

The conventional display device described above scans all row electrodes 21, 22, . . . 2fi, regardless of the number of row electrodes used for display. For this reason, even if the row electrodes used for display are only a fraction of all the row electrodes, all the row electrodes are scanned, resulting in a large amount of power consumed by extra matrix drivers and display elements.

[Means for resolving issues]

The present invention provides a discharge display element in which selected intersections of a plurality of row electrodes and column electrodes arranged opposite to each other are lit;
a circuit that sequentially scans the row electrodes in a time-division manner using a row electrode drive signal that includes a plurality of discharge pulses; and a circuit that scans the column electrodes sequentially in a time-division manner using a row electrode drive signal that includes a plurality of discharge pulses, and a column that includes discharge pulses that corresponds to input data while maintaining synchronization with the row electrode drive signal. In a display device having a circuit for selectively controlling electrode drive signals, a row electrode setting circuit for scanning a portion of a plurality of row electrodes that becomes a display area, and an enabler for preventing unnecessary row electrodes from being scanned. It is characterized by being equipped with a pulse generation circuit.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of one embodiment of the present invention.

The reference numerals assigned to the various components in FIG. 1 correspond to those in FIG. 2, and their operation is as previously described. Therefore, the parts that are different from FIG. 2 will be explained. 21.22...21,2 of the 2° row electrodes
□ Consider the case where 2n/2 (assuming n is an even number) row electrodes are used as a display area. 21, 22,
...The row electrodes up to 2n/2 are sequentially scanned in the same manner as in the conventional driving method, and when the scanning of 2n/2 row electrodes is completed, the number n/2 of row electrodes set by the row electrode setting circuit 17 is enabled. When the number of scanning row electrodes counted by the counter built in the pulse generating circuit 18 exceeds the number, the enable pulse 20 is outputted from the enable pulse generating circuit 18 and all outputs of the decoder 12 become non-selected. Therefore, all outputs of the row driver 5 are also non-selected, so that no row electrode is scanned. In the conventional display element driving method, the enable pulse 20 is output over a period during which the row electrodes are scanned up to 2°/2+1...2°, so no discharge pulse is output from the row driver. That is, the display element 1 is not driven during the period when the enable pulse 20 is output.

〔Effect of the invention〕

As explained above, in the present invention, when only a part of the row electrode is used, the row electrodes to be scanned are limited to only the necessary row electrodes, so that discharge pulses are not output to the redundant row drivers, and the redundant row electrodes are scanned. Also, since no discharge pulse is applied, the power consumed by the display device is reduced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a block diagram of a conventional display element. DESCRIPTION OF SYMBOLS 1... Display element, 2... Row electrode, 3... Column electrode,
4... Display cell, 5... Row driver, 6... Column driver, 7... Discharge pulse, 8... Clock pulse, 9... Data control section, 10... Input data, 11
... Counter, 12... Decoder, 13... Scanning pulse, 14... Column drive signal, 15... Data signal, 16... Row drive signal, 17... Row electrode setting circuit,
18... Enable circuit, 19... Discharge pulse generation section, 20... Enable pulse, 21... Clock pulse output section. Representative patent attorney Otogen Uchihara 2 mouths

Claims (1)

[Claims] A discharge display element in which selected intersections of a plurality of row electrodes and column electrodes arranged opposite to each other are lit, and the row electrodes are sequentially moved in a time-division manner by a row electrode drive signal including a plurality of discharge pulses. In a display device that includes a scanning circuit and a circuit that selectively controls a column electrode drive signal including a discharge pulse in response to input data while keeping the column electrodes in synchronization with a row electrode drive signal, a row used as a display area. A display device comprising a row electrode setting circuit that scans only the electrodes.