JP3088494B2 - Display device driving method and device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving method of a display device for controlling a display device such as a plasma display.
In particular, the present invention relates to a method for driving a display device which is driven and controlled by a batch writing method.

[0002]

2. Description of the Related Art Conventionally, there are a line-sequential scanning system and a batch writing system as a driving method of a display device of this kind. In the line-sequential scanning method, a plurality of scan electrodes connected to a plurality of display cells are line-sequentially scanned one by one based on display data transferred from the outside, and write / erase operations are performed line-sequentially. This is a driving method for selectively displaying. In this line sequential scanning method, since a plurality of scanning electrodes are scanned in a line sequential manner, the screen rewriting speed per screen is limited, and the high speed rewriting is also limited.

In the batch writing method, a writing pulse is once applied to the entire screen, and after a batch writing, a selective display is performed using an erase pulse and an erase cancel pulse. That is, a simultaneous write pulse is applied to all the horizontal electrodes of a display panel in which a plurality of display cells are arranged in a matrix, and after collective writing, an erase pulse is sequentially and continuously applied to all the horizontal electrodes. I do. Further, by applying an erasure cancel pulse to a vertical electrode to which a display cell to be displayed among the vertical electrodes of the display panel is connected, a selective writing state is applied, and then a sustaining pulse is applied to increase the predetermined display emission luminance. obtain.

[0004]

Since the conventional display device driving method is configured as described above, high-speed rewriting cannot be performed in the line-sequential scanning method, and it does not correspond to the batch writing method. Have the following problems.

First, the period between the application of a write pulse applied to each horizontal electrode at a time and the application of an erase pulse applied sequentially to each horizontal electrode is determined by the position of the horizontal electrode (display cell). Therefore, uniform erasing characteristics cannot be obtained for display cells on the entire screen. This will be described with reference to FIG. 6. Since the application timing of the erase pulse is different, the periods T ₁ , T ₂ , and T ₃ from the application of the write pulse to the application of the erase pulse are different. Since the wall charges gradually attenuate in the different periods T ₁ , T ₂ , and T ₃ , the residual wall charges at the time of applying the erase pulse differ depending on the position of the display cell. Thus, as a result of the erase conditions change, in a sustain time, Y _b -X _i, horizontal Y _c -X _i - and it can not be performed is uniform erase operation display cell specified by the electrodes of the vertical Become. Wherein at the Y _b display cell specified by -X _i is possible substantially erasing operation, and shows a state that is not be erased at all the display cells specified by Y _c -X _i.

Second, when a write pulse is applied collectively, an excessive current flows to easily generate noise, and a large power supply capable of supplying a peak current is required. Thirdly, a method in which a plurality of display cells are divided into a plurality of regions and all writing and continuous erasing are performed for each region is conceivable. However, the number of write operations by the region division increases and the rewriting speed decreases.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to propose a method of driving a display device having a uniform erasing characteristic with a high rewriting speed.

[0008]

The driving method of a display device according to the present invention SUMMARY OF] is against the plurality of display cells arranged in a matrix, the erase pulse after the writing by applying the write pulse
Sequentially applying a further selectively <br/> applying an erase cancel pulse, any display cell specified in the erase cancel pulse selected as a write state of the display device for driving the display by the write pulse In the driving method, the plurality of display cells are divided into a plurality of display areas, and an erase pulse is applied to the entire other display area while a write pulse is applied to the entire divided display area. Things.

[0009]

According to the present invention, a plurality of display cells are divided into a plurality of display areas, and an erase pulse is applied to another display area while a write pulse is applied to one display area. The period from the application of the write pulse applied to each of the plurality of display areas to the application of the erase pulse applied sequentially is shortened, so that the erase characteristics are made as uniform as possible and the rewrite speed is increased. In addition, since a write pulse is applied at a different timing for each of the plurality of divided display areas, noise generation is suppressed, and a peak current value is suppressed to reduce the capacity of the power supply.

[0010]

【Example】

a) First Embodiment of the Present Invention Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 (A) and 1 (B).

The driving method of the display device according to the present embodiment is horizontal.
Scan electrode Y_a, Y_bEach horizontal scanning electrode
Y_aTo the horizontal scanning
Pole Y _bSustain pulse and write pulse
Apply loose. Further, the vertical signal electrode X_aIs 0V (G
ND) level no signal state is maintained, and X_bTo
Applies an erase cancel pulse.

[0012] The application of the respective signals, combined drive waveform Y _a -X _a applied to the display cell C1 has a waveform including a sustain pulse and the erase pulse, the display cell C1 emission is eliminated. Synthetic drive waveform Y applied to display cell C2
_{a− Xb} is a waveform including a sustain pulse and a signal in which the erase pulse is canceled by the erase cancel pulse,
The display cell C2 maintains the previous state and remains light emitting or non-light emitting. Composite driving waveform Y _b applied to display cell C3
-Xa has _a waveform including _a sustain pulse and a write pulse (including a sustain pulse), and the display cell C3 performs a write operation. The combined drive waveform Y _b -X _b is applied to the display cell C4, the write operation is performed.
That is, the write operation can be performed on the display cells C3 and C4 simultaneously with the erase / maintenance operation of the display cells C1 and C2.

B) Second Embodiment of the Present Invention A method according to a second embodiment will be described with reference to FIGS. The driving method of a display device according to the second embodiment, and the region divided into two display cell groups A, B by dividing the plurality of horizontal scan electrodes Y _a1 to Y _bn of the plasma display 1 into two, the display cell a plurality of write pulses to the plurality of horizontal scan electrodes Y _b1 to Y _bn other electrode group B (or a) during the horizontal scan electrodes Y _a1 to Y _an, are applying the erase pulse of the group a (or B) And the vertical signal electrodes X _a and X of the display cell groups A and B, respectively.
By selectively applying an erase cancel pulse to _b ..., the display cells C1, C2 to Cn are selectively illuminated and drive-controlled.

Next, the method of this embodiment will be described in detail with reference to the operation timing chart shown in FIG. And at the same time sequentially applying erase pulses to the horizontal scan electrodes Y _a1 to Y _bn display cell group A, the same timing the write pulse following a common sustain pulse to the horizontal scan electrodes Y _b1 to Y _bn display cell group B Is applied. At this time the display cell group A, the vertical signal electrodes X _a and B hold the GND state, the vertical signal electrode X
_An erase cancel pulse is continuously applied to _b . Wherein a column示波form on behalf on each display cell C _aa1 -C _BBN each signal is applied _{Y a -X a, Y a -X} b, Y b -X a,
Composite waveform such as Y _b -X _b is to be applied.

[0015] Of the combined drive waveforms each display cell C _aa1 -C _BBN applied, for display cell C _aa1 -C _abn in the display cell group A, display cells are connected to the vertical signal electrode X _a C _aa1 since the -C _aan driving waveform of the Y _a -X _a are applied erased continuously, the display cell C _ab1 -C _abn connected to the vertical signal electrodes X _b Y _a -X
_Since the drive waveform _b is applied, the current state (written state or erased state) is maintained without being erased.

The display cell C in the display cell group B
_ba1 -C For _bbn, Y _a -X _a or Y _a -X _b
Is applied, the writing state can be set irrespective of one of the vertical signal electrodes _Xa and _Xb .

Further, after the above operation is completed, the display cell group A
By continuously applying a sustain pulse and a write pulse from the horizontal scan electrodes Y _{a1 to} Y _an to the display cell group B, and applying an erase pulse from the horizontal scan electrodes Y _{b1 to} Y _bn to the display cell group B. complete rewrite operation to the entire screen of the display 1, so that the light emission to the predetermined luminance required to display each display cell C _aa1 -C _BBN by continuous application of sustain pulses thereafter.

[0018] As described above, the more cells C _aa1 -C _BBN to the plasma display and bisected on the basis of the horizontal scan electrodes, application of the erase pulse from the time of application of the write pulse applied to each horizontal scanning electrodes The period T until the hour is half
Becomes Accordingly, it is possible to be wall charge accumulated in all the display cells C _aa1 -C _BBN is attenuated in a short period T became 1/2, homogenization of the erase operation by minimizing the attenuation of the wall charges can be achieved . Further, the write pulse is applied to each of the display cell groups A and B.
Therefore, the peak current value can be suppressed because the application timing is different.

C) Third Embodiment of the Present Invention A third embodiment will be described with reference to FIG. In the figure, in the driving method of the display device according to the third embodiment, all the display cells of the plasma display 1 are divided into three display cell groups A, B,
C, the write pulse is applied to the display cell group B while the erase pulse is applied to the display cell group A, and the display is performed while the erase pulse is applied to the display cell group B. Drive control is performed on the cell group C so that a write pulse is applied.

By the drive control according to the method of the present embodiment,
For each display cell group B, C (or C), a write pulse is sequentially applied at predetermined intervals without being applied simultaneously with the write pulse applied to the other previously displayed display cell group A (or A, B). , Each display cell group A,
Periods T _A (T _AS , T _AL ), T _B (T _BS , T _B , T _B ) from the application of each of the write pulses B and C to the application of each of the erase pulses
T _BL ) and T _C (T _CS , T _CL ) are shortened. That is, the periods T _A , T _B , and T _C are the periods in the prior art (FIG. 6).
(See period T ₃ in FIG. ₃ ), the decay of the wall charges accumulated in each display cell can be minimized, and the display cells in the entire screen of the plasma display can be minimized. , A uniform erasing characteristic can be obtained.

A sustain pulse is continuously applied to the display cell groups A, B, and C after a write scan period in which a write pulse and an erase pulse are applied is completed. When the sustain period to which the sustain pulse is applied ends, one screen rewriting time is completed.

D) Another embodiment of the present invention Another embodiment of the present invention will be described with reference to FIG. Same figure
In the driving device of the display device according to the present embodiment,
The horizontal scanning electrodes of the display 1 are divided and connected to each other
Multiple Y drivers 2₁, ~, 2_nAnd the plasm
X-dry to which the vertical signal electrodes of the matrix display 1 are connected
3 and each of the Y and X drivers 2₁, ~, 2_n, 3
An operation control circuit 4 for suppressing each of the plurality of Y-addresses.
Liver 2 ₁, ~, 2_nY driver 2 of one₁(Or 2
_Two, ~, 2_n) Is the display area of the horizontal scanning electrodes divided into regions.
Group 1_A(Or 1_B~ 1_NApply a write pulse to
While other Y driver 2_Two~ 2_nIs the area
Display cell group 1 of horizontal scanning electrodes_B(Or 1_A, 1
_C~ 1_N) Is applied.

The operation of the driving device based on the above configuration is the same as that in the embodiment of the invention in which the plasma display 1 is divided into a plurality of regions. e) Other embodiments of each invention In each of the above embodiments, the display device is configured as a plasma display. However, the display device such as electroluminescence (EL), light emitting diode (LED), liquid crystal (LCD), etc. It can also be composed of elements.

The display device can be divided into an arbitrary number of regions. In particular, on the assumption that uniform erasing characteristics can be obtained for display cells on the entire screen, the number of write operations by division is minimized. The numerical value of the area division is desirable.

In each of the above embodiments, the sustain period for applying the sustain pulse is applied collectively at the end of one screen rewriting time. However, the write operation applied to each display cell group divided into regions is applied. It is also possible to adopt a configuration in which a pulse is dispersed and applied several cycles after the pulse is applied.

In the above-described embodiment, the method of driving the erasing operation has been described with the method of erasing the selected cell by a combination of the erasing pulse and the erasing cancel pulse. A method is also possible in which a pulse having a polarity is applied, and an erase pulse synthesized is applied to the selected cells crossing each other to directly erase.

[0027]

As described above, in the present invention, a plurality of display cells are divided into a plurality of display areas, and while a write pulse is applied to one display area, an erase pulse is applied to another display area. Since the voltage is applied, the period from the time of applying the write pulse applied to each of the plurality of display areas to the time of applying the erase pulse sequentially applied is shortened, the erase characteristics are made as uniform as possible, and the rewriting speed is reduced. Speed up. Also,
Since a write pulse is applied at a different timing for each of the plurality of divided display areas, noise generation is suppressed, and a peak current value is suppressed to reduce the power supply capacity.

[Brief description of the drawings]

FIG. 1 is a diagram showing a manner of applying a write pulse and an erase pulse for explaining a first embodiment of the present invention.

FIG. 2 is a circuit diagram of a plasma display for explaining a second embodiment of the present invention.

FIG. 3 is a diagram showing various signal waveforms and a timing chart for explaining the operation of the embodiment shown in FIG. 2;

FIG. 4 is an operation timing chart for explaining a third embodiment of the present invention.

FIG. 5 is a block circuit configuration diagram for explaining another embodiment of the present invention.

FIG. 6 is an operation timing chart for explaining a problem of a conventional display device driving method.

[Explanation of symbols]

1 ... plasma display _{2 1, ~, 2 n ...} X driver 3 ... Y driver 4 ... operation control circuit X _a, X _b ... vertical signal electrodes _{Y a, Y b, Y a1} , Y a2 ~Y an, Y b1, Y _b2 to Y _bn ... horizontal scanning electrodes C1, C2, C3, C4, C aa1 ~C bbn ... display cell

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G09G 3/28 G02F 1/133 G09G 3/288

Claims (4)

(57) [Claims] 1. A against the plurality of display cells arranged in a matrix, a display device sequentially applies the erase pulse after writing by application of the write pulse, to drive display by any display cells with selective write state In the driving method, the plurality of display cells may be divided into a plurality of display regions, and an erase pulse may be applied to another display region while a write pulse is applied to one of the divided display regions. A method for driving a display device, comprising: 2. The driving method for a display device according to claim 1, wherein a sustaining pulse for maintaining a driving display is applied to the plurality of display areas after a selective driving by a driving pulse including a writing pulse and an erasing pulse. One drive cycle,
A driving method for a display device, wherein the driving cycle is periodically repeated. 3. A becomes includes a display panel portion formed with a plurality of display cells formed at intersections of a plurality of scanning electrodes and signal electrodes are arranged in matrix form (1), said plurality
After writing by applying a write pulse to a number of display cells
Erasing pulse is applied sequentially to select display cells
In a driving device for a display device that displays driving states, a plurality of scanning driving units (2 ₁ ,..., 2) in which a plurality of scanning electrodes of the display panel unit (1) are divided into one or a plurality of scanning electrodes and connected. _n ), and one of the plurality of scan drivers (2 ₁ ,..., 2 _n ) applies a write pulse to the scan electrode while the other scan driver becomes Scanning driving means (2) for applying an erasing pulse to the scanning electrode ;
Driving device for a display device, characterized in that provided. 4. A driving device for a display device according to claim 3, wherein
At Connected to one or more signal electrodes of the display panel section (1)
And an erase cancel pulse for canceling the erase pulse.
Alternatively, a selection pulse such as an erase pulse with reverse polarity is applied to the signal electrode.
Signal driving means (3) for selectively applying voltage.
Characteristic display device driving device.