JP2628560B2 - Gas discharge panel device with memory function - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Table of Contents] Outline Industrial application field Conventional technology (FIG. 7) Problems to be solved by the present invention (FIGS. 8 and 9) Means for solving the problem (FIG. 1) Function Embodiment (FIGS. 2 to 6) Effect of the Invention [Overview] Regarding erasing control of a display line of a gas discharge panel device with a memory function, in particular, an AC type gas discharge panel (AC-PDP). The object of the present invention is to prevent surplus lighting and forgetting to be turned off that occur when the line mode is converted, to ensure the erasing operation of the surplus display line, and to improve the display quality and reliability of the display panel. X-side drive means for selecting the X-side discharge electrode based on the second data, Y-side drive means for selecting the Y-side discharge electrode based on the second data, and X, Display means for generating gas discharge light between the Y-side discharge electrodes, In the gas discharge panel device with a memory function comprising a control means for controlling the output to the X, Y side driving means and the display means, identification means for identifying a scanning mode based on scanning control data from the control means, The X, Y side discharge electrodes are provided with forced erasing means for stopping generation of gas discharge light based on the scanning mode.

[Industrial applications]

The present invention relates to a gas discharge panel device with a memory function, and more specifically, to erasure control of a display line of an AC gas discharge panel (AC-PDP).

2. Description of the Related Art In recent years, in a portable computer system, a gas discharge panel device with a memory function has been used as a flat display device used in combination with a keyboard unit.

According to this, a device having a multi-scan function capable of converting the mode of a display line to speed up the display processing is desired.

[Conventional technology]

 7 to 9 are explanatory diagrams according to a conventional example.

FIG. 7 shows a configuration diagram of a gas discharge panel device with a memory function according to a conventional example.

In the figure, a gas discharge panel device with a memory function is:
Data-side drivers (X) 1a, 1b for inputting display data D1 and selecting X-side discharge electrodes 3a, and line-side drivers (Y) 2a, 2b for inputting line data D2 and selecting Y-side discharge electrodes 3b. And data and line side drivers 1a, 1b
And the X, Y side discharge electrodes 3a, 3 designated by the outputs of 2a, 2b
Drive control of the line and data side drivers 1a, 1b, 2a, 2b by inputting write data D5 and control data D6 from the display panel 3 generating the gas discharge light P between b and the host microprocessor unit (MPU). And a control circuit 4 for performing the control.

The function of the device is that the display data D1 is first written to the dot position specified by the line and data-side drivers 1a, 1b and 2a, 2b, so that the X, Y-side discharge electrodes 3a,
The sustain pulse (discharge sustaining voltage) between 3b increases.
Thereafter, this voltage becomes the discharge sustaining voltage, and the electrode 3
The plasma state is maintained between a and 3b. Thereby, gas discharge light is generated, and pixel display is performed on the display panel 3.

[Problems to be Solved by the Invention] According to the conventional example, the display panel 3 in the display mode of 480 lines may be used in the display mode of 350 lines. This is due to the compatibility between the 350-line display panel and the 480-line display panel, and the demand for faster display processing by introducing the multi-scan function.

However, when a 480-line display panel is used in the 350-line mode, the following problem may occur.

8 (a) and 8 (b) are diagrams for explaining the problems of the conventional example. As shown in FIG. 8 (a), the display panel 3 of 480 lines is used.
Is used in the 480 line mode, one vertical synchronization period (1 ▲ ▼), that is, one screen data
Line data of 480 lines or more is included.

However, when the display panel of 480 lines is used in the 350 line mode, only 449 lines are displayed in 1 ▲ ▼, and the data is not accessed after 450 lines, resulting in an undefined state. This is a state in which the sustain pulse is applied between the X and Y discharge electrodes 3a and 3b after the 450th line, and if write data is input, the X and Y side discharge electrodes 3a and 449 before the 449th line are input. As in 3b, the writing process can be performed.

For this reason, as shown in the state diagram of the display panel in FIG. 9, when shifting from the 480-line mode display to the 350-line mode display, the erasing operation was incomplete for some reason. There is a case where the line mode display remains and the user forgets to turn off the light A or the surplus lighting B due to noise may occur.

As a result, there is a problem that the display quality and reliability of the display panel 3 are reduced.

The present invention has been made in view of the problems of the conventional example, and prevents an excessive lighting or forgetting to be turned off that occurs when a mode conversion of a display line is performed, thereby ensuring an erasing operation of a surplus display line, It is an object of the present invention to provide a gas discharge panel device with a memory function capable of improving display quality and reliability of a display panel.

[Means for solving the problem]

FIG. 1 shows a principle diagram according to a gas discharge panel device with a memory function of the present invention.

The device uses the X-side discharge electrode based on the first data D1.
An X-side drive unit 11 for selecting the Y-side discharge electrode 18 based on the second data D2;
X, Y side discharge electrode 17, based on the output of the X, Y side driving means 11, 12,
A display means 13 for generating gas discharge light P between the X and Y
In a gas discharge panel device with a memory function comprising: side driving means 11, 12 and a control means 14 for controlling output to a display means 13, a scanning mode is identified based on scanning control data D3 from the control means 14. The above object is achieved by providing a discriminating means 15 and a forced erasing means 16 for stopping generation of the gas discharge light P between the X, Y side discharge electrodes 17, 18 based on the scanning mode. .

[Action]

According to the present invention, the identification means 15 and the erasing means 16 are provided.

For example, when the scan mode of the display line is converted, the scan mode is identified from the scan control data D3, and the surplus display line is determined. As a result, the forced erasure data D4 for forcibly turning off the gas discharge light P of the surplus display line erroneously displayed is output to the Y-side driving means 12.

For this reason, the forced erasure operation of the surplus display line is ensured, and it becomes possible to prevent surplus lighting, forgetting to turn off, etc. as in the conventional example.

This makes it possible to improve the display quality and reliability of the display panel.

〔Example〕

Next, an embodiment of the present invention will be described with reference to the drawings.

2 to 6 are views for explaining a gas discharge panel device with a memory function according to an embodiment of the present invention, and FIG. 2 is a configuration diagram of the gas discharge panel device with a memory function according to the embodiment of the present invention. Is shown.

In the figure, reference numerals 21a and 21b denote data drivers (upper) and (lower) which are embodiments of the X-side driving means 11, which input the display data D1 and select the X-side discharge electrode 23a.

Reference numerals 22a and 22b denote line-side drivers (right) and (left) as one embodiment of the Y-side driving means 12, which input the line data D2 and select the Y-side discharge electrode 23b.

23 is a display panel as an embodiment of the display means 13,
It constitutes a flat display device in a portable type computer system and is used in combination with a keyboard unit. The display panel 23 has an X-side discharge electrode
It has a gas discharge panel structure with a memory function consisting of a discharge electrode 23a, a Y-side discharge electrode 23b, and a discharge cell storage insulator (not shown).

The display principle of the panel 23 is as follows. In a discharge sustaining state (memory state) in which a low voltage pulse is applied between the X and Y side discharge electrodes 23a and 23b, first, the display data inputted to the data side drivers 21a and 21b are displayed. One of certain X addresses is designated based on D1. Next, the designated X, Y side discharge electrodes 23a, 23b
An address voltage is applied in between to generate wall charges that generate a discharge sustaining voltage. As a result, the space between the electrodes 23a and 23b becomes a plasma state, and the gas discharge light P is generated. And Y
A dot bright point is displayed through the glass surface of the side discharge electrode 23b. In the embodiment of the present invention, it is assumed that a 640 × 480 class display panel is used in a 350 line mode.

Reference numeral 24 denotes a drive control circuit as an embodiment of the drive control means 14, which inputs write / erase data D5 and control data D6 from the host MPU and outputs display data D1, line data D2 and scan control data D3. Is what you do.

Reference numeral 25 denotes a line mode identification circuit as an embodiment of the identification means, which identifies the scanning mode of the display panel 23 by inputting the scanning control data D3 from the control circuit 24.

Reference numeral 26 denotes a forced erasure signal generation circuit as an embodiment of the forced erasure means 26, which outputs forced erasure data D4 for forcibly turning off the light emission of the excess display line based on the scanning mode. Here, the surplus display line is 4 when the display panel in the 480 line mode is used in the 350 line mode.
Refers to lines after 50.

Further, including a line mode identification circuit 25, a forced erase signal generation circuit 26, and a conventional Y data generation circuit,
It is called a surplus line forced erasure circuit.

FIG. 3 is a configuration diagram of a surplus line forced erasure circuit according to an embodiment of the present invention.

In the figure, a line mode identification circuit 25 includes a DFF (D flip-flop) circuit 51 which receives a vertical synchronizing signal ▲ ▼ and a horizontal synchronizing signal ▲ ▼ serving as scanning control data D3 and outputs a counter clear signal VS;
▼ A two-input OR circuit 52 that inputs a signal and a signal VS to output a latch signal LHV, a counter 53 that outputs a count value QA using an inverted signal of the signal ▼ as a clock signal CLK, and a clock that latches the latch signal LHV. And a latch circuit 54 for latching the count value QA and outputting the last counter value QB, and an inverter 55 for inverting the ▲ ▼ signal.
Consists of

The forced erase signal generation circuit 26 compares the count value QC obtained by counting the clocks in the 480 line mode with the last count value QB, and outputs a line identification pulse Y1, a comparator 61, and an inverter 62 that inverts the pulse Y1. , The inverted pulse signal
The latch circuit 63 latches Y1 and outputs a forced erase pulse DE.

The Y data generation circuit 27 is provided with circuits 73 and 74 for superimposing the forced erase pulse DE on the conventional circuit. That is, the circuit 27 receives the clock CK and the write control signal ENB and outputs a count value QC.
And a comparator 72 for comparing the count values QA and QC to output a comparison output signal Y2, and a two-input AND circuit for performing a two-input AND logic operation on the first write control signal ENA and the forced erase pulse DE
73, and line data obtained by performing a two-input OR logic operation on the resultant output signal and output signal Y2 and superimposing a forced erase pulse signal
It comprises a two-input OR circuit 74 that outputs D2, an inverter 75 that inputs a clock CK to create a Y clock, and a two-input AND circuit 76.

Thus, a discharge panel device with a memory function according to the embodiment of the present invention is configured.

Next, the forced erasing operation when the device is changed from the 480 line mode to the 350 line mode will be described.

FIG. 4 is a time chart of the line mode identification circuit according to the embodiment of the present invention.

In the figure, first, a vertical synchronization signal ▲ ▼ and a horizontal synchronization signal ▲ ▼ are
To identify the line mode.

At this time, in the circuit 25, the ▲ signal is input to the DFF circuit 51 using the ▲ signal as a clock, and the counter clear signal VS, which is the output thereof, is output to the counter 53.
Is output to Next, the counter 53 counts the ▲ signal using the ▲ signal as a clock and outputs a count value QA = 449. This makes it possible to identify that the display line mode is the 350 line mode. At this time, the count value QA is
Is used as a clock to be latched by the latch circuit 54.

FIG. 5 is a time chart for explaining a forced erase operation according to the embodiment of the present invention.

In the figure, first, the horizontal synchronizing signal
The system clock SCK is counted from 0 to 480 via the counter 71 based on the clear signal CLRB based on the signal. Next, the comparator 72 compares the count value QC with the current display line count value QA = 5. Here, when the count values QA and QC match, the comparison output signal Y2
= “1” is output. This indicates a state in which the writing operation is not performed on the surplus display lines after the 450th line. If left in this state, excessive lighting or the like occurs as in the related art. Therefore, in the embodiment of the present invention, the count value QB = 449 and the count value QC identified in FIG.
= 449 is compared via the comparator 61.

Next, when the output of the comparator 61 is "1", that is, when QB = QC, the line identification pulse Y1 is raised.
As a result, the forced erase pulse DE rises for the surplus lines after 450 lines and falls by the clear signal CLRA. This is referred to as a first write control signal.
Based on ENA, two-input AND circuit 73 and two-input OR circuit 74
Is superimposed on the comparison output signal Y2. This superimposition operation is performed about once per 1 ▲.

As a result, the line data D2 on which the forced erase signal is superimposed
Is output to the line-side drivers 22a and 22b. At this time, the Y clock generated based on the second write control signal ENB defining the generation of the display data D1 and the system clock SCK is transmitted along with the line data D2 to the drivers 22a and 22a.
Output to b.

In addition, TA indicates a period in which the display data D1 is generated by one access in the 480 line mode, and TB indicates a period in which the display data D1 is generated in the 350 line mode. This is a period during which access is not performed in the TC350 line mode, and a period during which erasing is forcibly performed.

FIG. 6 is a diagram for explaining a forced erase operation according to the embodiment of the present invention.

In the figure, the line data D2 of the serial column from the Y data generation circuit 27 is first sent to the line side driver circuit 22a.
Is input to the shift register 28 based on the Y clock. The line data D2 output from the shift register 28 is converted into parallel data by the latch circuit 29. The line data D2 of this parallel row is
Is input, the Y-side discharge electrode 23b connected to the circuit is selected, and between the electrode 23b and the X-side discharge electrode 23a, the previously displayed write data is erased or the 450th line or later is erased. Is performed.

Thus, according to the present invention, the line mode identification circuit 25 and the forced erasure signal generation circuit are provided.

For this reason, even when the 480 line mode is converted to the 350 line mode, the vertical synchronization signal
▼, surplus display lines after 450 lines are determined from the horizontal synchronization signal ▲ ▼, and the gas discharge light P and the like of the erroneously displayed surplus display line can be forcibly turned off.

Thereby, the forced erasing operation of the surplus display line is ensured, and it becomes possible to prevent the surplus lighting or forgetting to turn off as in the conventional example.

〔The invention's effect〕

As described above, according to the present invention, even if the scanning mode is converted from the 480-line mode to the 350-line mode by the redundant line forced erasing circuit, generation of gas discharge light related to the redundant line of the display panel is performed. Can be stopped.

Therefore, the erasing operation on the surplus display line can be performed more reliably than in the conventional example.

As a result, the display quality and reliability of the display panel are improved, which greatly contributes to the production of a gas discharge panel device with a memory function having a multi-scan function.

[Brief description of the drawings]

FIG. 1 is a principle diagram of a gas discharge panel device with a memory function according to the present invention, FIG. 2 is a configuration diagram of a gas discharge panel device with a memory function according to an embodiment of the present invention, and FIG. FIG. 4 is a time chart of a line mode identification circuit according to an embodiment of the present invention, and FIG. 5 is a diagram showing a forced erase operation according to the embodiment of the present invention. FIG. 6 is a diagram illustrating an erasing operation according to an embodiment of the present invention, FIG. 7 is a configuration diagram of a gas discharge panel device with a memory function according to a conventional example, and FIG. FIG. 9 is a state diagram of a display panel for explaining a problem of the conventional example. (Explanation of reference numerals) 11 ... X side driving means, 12 ... Y side driving means, 13 ... Display means,
14 ... control means, 15 ... identification means, 16 ... forced erasure means, 17 ...
X-side discharge electrode, 18 ... Y-side discharge electrode, D1 ... first data,
D2: second data, D3: scan control data, D4: forced erasure data, P: gas discharge light.

Claims (1)

(57) [Claims] An X-side driving means (11) for selecting an X-side discharge electrode (17) based on first data (D1), and a Y-side discharge electrode (18) based on second data (D2). ) And gas discharge light (P) between the X, Y side discharge electrodes (17, 18) based on the outputs of the X, Y side drive means (11, 12). A gas discharge panel device with a memory function, comprising: display means (13) for generating the light; and control means (14) for controlling outputs to the X, Y side driving means (11, 12) and the display means (13). An identification means (15) for identifying a scanning mode based on scanning control data (D3) from the control means (14), and the X, Y side discharge electrodes (17, 18) based on the scanning mode. A gas discharge panel device with a memory function, comprising: forced erasing means (16) for stopping generation of gas discharge light (P).