JPS63103296A - Driving of display element - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for driving a display element, and more particularly, the present invention relates to a method for driving a display element, and in particular, the present invention relates to a method for driving a display element, and in particular, a method for driving a display element, in which the intersection points 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 are It concerns the driving method of external electrode type discharge display panels, so-called plasma display panels.

2. Description of the Related Art In this type of plasma display panel (hereinafter abbreviated as display panel), there are a plurality of generally transparent column electrode groups parallel to each other, and a plurality of generally opaque row electrode groups parallel to each other. A method is generally known in which the electrodes are arranged in a trix shape, an ionizable gas is interposed between the two electrode groups, and the intersection of a selected row electrode and a selected 9th column electrode is displayed by discharge light emission.

By controlling the electrode selection method of the row electrode group and the column electrode group in accordance with the input signal on the display panel 2, an optical image corresponding to the input signal can be displayed. For example, one of the row electrode groups and column electrode groups, for example, each electrode in the row electrode group, is selected and scanned sequentially in a time-division manner, and the other electrode group, for example, each electrode in the column electrode group, is selected and scanned in sequence. By controlling the selection based on the input signal while maintaining synchronization with the scanning, an optical image corresponding to the input signal can be displayed on the display panel surface. In an external electrode type display panel, it is necessary to drive it with an AC voltage, and the drive signal applied to the row electrode group and column electrode group includes a high frequency discharge pulse called a toggle pulse.

The relevant drive system will be explained with reference to the drawings.

FIG. 2 is a block diagram of two conventional display systems. The display element shown in Figure 1 has only one row electrodes parallel to each other (unless specifically shown).

(suffixes are omitted) and mutually parallel column electrodes 3 orthogonal to each other, and display cells are provided at each matrix intersection. Furthermore, each of the row electrodes is connected correspondingly to each output terminal f of the row driver S, and each electrode of the column electrodes 3 is correspondingly connected to each output terminal of the column driver base. Each row, column driver! , B are connected to the discharge pulses necessary for discharging the display element l. On the other hand, a clock pulse t for controlling the timing at which the row and column electrodes 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 base. has been done. Furthermore, the clock pulse is input to the counter l/ and its output is decoded f
/:1 is connected to the human power, and its output is further connected to the input of the row driver S.

Next, the operating principle of the drive system shown in FIG. 2 will be described.

The clock pulse t is counted down by a number equal to the number n of row electrodes to be driven in the counter //, and then decoded in the decoder /2, and the output thereof has a pulse width t (clock pulse period) and a period nt. generates a scan pulse of /3. Each scan pulse/31. /,7
2.../3n are each shifted in phase by a pulse width t, and each time a clock pulse t is input, a scanning pulse/,? 1, /32.../, 7n sequentially generate outputs. The scanning pulse 13 is mixed with the discharge pulse 7, inputted to the row driver S, and stepped up by 1 to the voltage required for discharge, producing the row drive signal /6 and the corresponding row electrodes 1 . λ2... sequentially drives controllers n.

On the other hand, the input data IO corresponds to the scanning of the row electrodes.
Each clock pulse l is input to the data system uMq, where it is arranged to become a signal to the corresponding column electrode, and its output is sent to the column driver 6, where it is mixed with the discharge pulse and then outputs the voltage necessary for discharge. is stepped up to produce a column drive signal /4' to drive the corresponding column electrode 3.

The discharge pulse in the column drive signal /4' and the discharge pulse in the row drive signal /6 are applied in opposite phases to each other. The drive signal /4' and the row drive signal /6 are added together, and the voltage becomes higher than the discharge start voltage, causing discharge and light emission.

In particular, by controlling the scanning of the row electrodes and the input timing of input data to the column electrodes 3, it is possible to cause any display cell on the display element to emit light.

Conventionally, this type of display panel changes from a normal display mode in which selected intersections turn on when there is input data, and turns off at non-selected intersections when there is no input data, depending on the presence or absence of input data, by a reverse signal. Even when switching to the inverted display mode in which the lighting and extinguishing of non-selected intersections are reversed, the frequency of the discharge pulse remains the same as in the normal display mode, and the display element is driven.

Problems to be Solved by the Invention However, in the conventional display element driving method described above, the number of lighting intersections in the normal display mode and the number of lighting intersections in the inverted display mode are Although the number of lighting intersections increases, the frequency of the discharge pulse is driven around the same frequency, so when switching from the normal display mode to the inverted display mode, the matrix driver and other display elements It has the disadvantage that it is driven with a tendency to increase power consumption.

In addition, in the reverse display mode, there are more lighting intersections serving as the background than in the normal display mode, so that the apparent display appears brighter, and when switching to the normal reverse display mode, there is an abnormality due to the change in apparent brightness. There was a feeling.

The present invention has been made in view of the above-mentioned conventional situation,
Therefore, an object of the present invention is to provide a novel method for driving a display element, which makes it possible to solve the above-mentioned problems inherent in the conventional technology.

Means for Solving the Problems In order to achieve the above object, the method for driving a display element according to the present invention includes switching from the normal display mode to the inversion display mode by a reverse signal output from an inversion mode switching section. When performing this, the frequency of the matrix drive signal can be increased by providing a discharge pulse generating section or the like with a function of varying the discharge pulse using the reverse signal, and lowering the discharge pulse in the reverse display mode than in the normal display mode. It is characterized by lowering and.

Originality of the Invention Regarding the increase in power consumption of the matrix driver when switching from the normal display mode to the inverted display mode in the conventional display element driving method described above.

According to the present invention, the amount of increase in power consumption is reduced by lowering the frequency of the discharge pulse in the reverse display mode, and the luminance brightness depends on the frequency of the discharge pulse. The present invention has an original content of reducing the discomfort caused by the apparent brightness when switching the display mode by lowering the frequency.

Embodiment Next, a preferred embodiment of the present invention will be specifically explained with reference to the drawings.

FIG. 1 is a block diagram of a display system for explaining one embodiment of the present invention. The reference numbers assigned to each component in FIG. 1 correspond to those in FIG. To explain the different parts from FIG. 1, the discharge pulse generated by the discharge pulse generation section /f which divides the clock pulse is once inputted to the discharge pulse variable section 20. The discharge pulse frequency variable section is linked to the inversion mode switching section/7, and in the normal display mode the discharge pulse passes through the discharge pulse frequency variable section/9 without any change in frequency, but in the inversion display mode When switching to
As a result, the frequency of the discharge pulse input to the discharge pulse frequency variable section is variably controlled in the direction of decreasing F.

In this way, by varying the frequency of the discharge pulse in the normal inversion display mode (h), it is possible to reduce the increase in power consumption during the inversion display mode.

As described in detail, according to the present invention, when the number of lit dots in the inverted display mode becomes larger than the number of lit dots in the normal display mode in normal character display, etc., a discharge pulse is generated. A matrix driver that lowers the frequency than the sum! ,
The effect of reducing the increase in power consumption related to No. 6 can be obtained.

In addition, in the inverted display mode, there are more lighting intersections as a background than in the normal display mode, so the display appears brighter, but since the luminance of light emission depends on the frequency of the discharge pulse, the frequency of the discharge pulse is By lowering the brightness of the intersection that emits light as the background by lowering it in the reverse display mode, it is also possible to reduce the change in apparent brightness from the normal display mode.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a display system for explaining an embodiment of the present invention, and FIG. 1 is a block diagram of a conventional display system.

Claims (1)

[Claims] The row electrodes of the discharge display panel are sequentially scanned in a time-division manner using a row electrode drive signal including a plurality of discharge pulses, such that selected intersections between a plurality of row electrodes and column electrodes arranged opposite to each other are illuminated. In a method for driving a display element that provides a desired display by selectively controlling 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, the input data Corresponding to the presence or absence of the input data, the selected intersection lights up when the input data exists, and turns off as a non-selected intersection when the input data does not exist. The display is characterized in that when the display is reversed to enter an inverted display mode in which lighting and extinguishing are reversed from the normal display mode, the frequency of the discharge pulse is lowered than in the normal display mode. How to drive the element.