JPH0429293A - Display system for plasma display device - Google Patents

Abstract

PURPOSE:To improve the picture luminance by dividing a display panel into two by the center in the vertical direction and providing two driving circuits and using one driving circuit to scan the display panel from the center to the top and using the other to scan the display panel from the center to the bottom. CONSTITUTION:A display panel 10 is divided into two by the center in the vertical direction, and two driving circuits 6 and 7 are provided, and the display panel is simultaneously scanned in the upper part and the lower part upward from the center division part to the top line and downward from the center division part to the bottom line respectively. Consequently, the display panel 10 is simultaneously scanned in parallel to extend the display period (panel lighting period). Thus, the picture luminance on the display panel 10 is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to, for example, a DC type plasma display system with a memory function.

[Conventional technology]

FIG. 5 is a block diagram of a conventional DC type plasma display device with a memory function. In the figure, 1 is a synchronization signal input terminal, 2 is a video signal input terminal, 3 is a drive pulse generation unit that receives the synchronization signal and generates a display panel drive signal;
Reference numeral 4 denotes a control signal generation section which receives the synchronization signal and generates a control signal for use in video signal conversion; 5 denotes a video signal conversion section which receives the output of the video signal and control signal generation section 4 and generates a display video signal; and 8 An upper anode drive unit receives the output of the video signal converter 5 and the output of the drive pulse generator 3 to drive the upper anode of the display panel 10; similarly, 9 is a lower anode drive unit that drives the lower anode; 11 is a drive This is a cathode drive unit that receives the output of the pulse generator 3 and drives the cathode.

DC-type plasma display devices with memory function take advantage of the fact that charged particles generated by discharge gradually decrease over time after the discharge stops, and that when charged particles are distributed in space, the restriking voltage decreases. In this method, pulse discharge of a DC type display cell is continuously performed.

Generally, to display an image using such a display having a matrix-type electrode arrangement, for example, one row of horizontal electrodes is selected, and all vertical electrodes are driven in parallel to display an image between the horizontal and row electrodes. All pixels are written at the same time, discharge is started, and discharge is maintained for a certain period of time. On the other hand, scanning or pixel writing is performed sequentially only in the vertical direction. Additionally, in addition to these electrodes, an auxiliary electrode is provided in the vertical direction, and a pilot discharge for scanning is performed between the above-mentioned horizontal electrodes to facilitate the start of the discharge between the above-mentioned two electrodes. Take advantage of the effect.

The above-mentioned horizontal electrode is called a cathode, the vertical electrode is called a display anode, and the auxiliary electrode is called a scan anode.

On the other hand, as the display panel 10 becomes larger, the display anode has a relatively high operating frequency from the viewpoint of discharge phenomena, and since the line capacitance of the electrode affects the drive waveform, it is necessary to vertically divide the display panel 10 into upper and lower parts. is common. At this time, the display anode and scanning anode are divided into upper and lower parts.

A conventional example will be explained below.

In FIG. 5, the drive pulse generator 3 generates a writing pulse, a sustain pulse, and a scanning anode pulse as anode signals based on the synchronization signal, and as cathode signals, a scanning pulse,
Create erase pulse, reset pulse, and shift lock. The control signal generator 4 generates various signals for controlling the A/D converter and field memory in the video signal converter 5 based on the synchronization signal. In the video signal converter 5, the video signal is converted into a digital signal of (k is a natural number) by an A/D converter, stored in a field memory, and then read out at high speed for each focus.

The read period for each bit is called a subfield.

Furthermore, as mentioned above, since the display panel 10 is divided into an upper part and a lower part, it is necessary to read out the video signal for the upper part display and the video signal for the lower part display separately. The signal is read out as a video signal for display, and then the signal from the division point to the bottom line is read out as a video signal for lower display. This state is shown in FIG. 4 fat.

Next, the driving section surrounded by the broken line in FIG. 5 will be explained with reference to the timing diagram in FIG. 6.

The upper anode drive section 8 receives a write pulse and a sustain pulse from the drive pulse generator 3, and receives an upper display video signal from the video signal converter 5, and displays an image in the gap between successive sustain pulses as shown in FIG. An anode drive signal is created in which write pulses selected according to the signal exist. The lower anode drive unit 9 also receives the lower display video signal and performs a similar operation.

The cathode drive unit 11 receives a reset pulse, a scan pulse, an erase pulse, and a shift clock from the drive pulse generator 3, and generates a reset cathode signal that triggers the start of scanning as shown in FIG. 6, and a combination of the scan pulse and the erase pulse. , each signal is transmitted over time to the RC, C, C2, .

FIG. 6 shows a case where a display cell in the second row and second column of a display panel having display cells in eight rows and m columns is lit.

A reset discharge is caused by the reset cathode signal, and scanning is then performed sequentially every horizontal period H. In this example, the discharge starts at the point where the C2 scan pulse and the UA2 write pulse overlap, and the discharge is maintained until the leading edge of the erase pulse. The sustain period is determined by the weight of each bit when the video signal is digitized.

FIG. 3(a) shows how a conventional display panel is driven, with time plotted on the horizontal axis. The vertical direction represents the top and bottom of the display panel. Here, if the number of quantization bits, which is the number of pixels in the horizontal direction, is k, the horizontal period is H1, the number of lines on the screen is n, and the LSB display (maintenance) period is X, then the vertical period ■ is expressed as follows: When the number of lines is -, then the total display period X of all bits is expressed as follows.

Generally, when displaying a video, the horizontal period H1 and the vertical period ■ and the number of quantization bits are fixed, so the total display period X becomes smaller in proportion to the number of lines n.

[Problem to be solved by the invention]

Conventional DC type plasma display devices with memory function use the above-mentioned scanning method;
Since the period (no display) increases in proportion to the number of cathode lines, there is a problem in that when the number of cathode lines is large, the screen brightness decreases.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a plasma display method that can improve screen brightness by shortening the display dwell period.

[Means to solve the problem]

In this invention, the display panel 10 is divided into two parts at the center in the vertical direction, and two systems of drive circuits 6 and 7 are provided. is scanned from the center of the display panel 10 toward the bottom.

[Effect]

In the display method according to the present invention, at the top of the display panel 10, from the central dividing part of the display panel 10, upward toward the top line, and at the bottom of the display panel 10, from the central dividing part, downward from the central dividing part toward the bottom line, respectively. Continue scanning.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

In Fig. 1, numeral 1 is a synchronization signal input terminal, 2 is a video signal input terminal, 3 is a drive pulse generator that receives the synchronization signal and generates a display panel drive signal, and 4 is a drive pulse generator that receives the synchronization signal and converts the video signal. A control signal generation unit that generates a control signal; 5 a video signal conversion unit that receives the output of the video signal and control signal generation unit 4 and generates a display video signal; 6 a display panel 10 that receives the output of the drive pulse generation unit 3; 7 is an upper cathode drive unit that drives the upper cathode of the display bar 10, 7 is a lower cathode drive unit that receives the output of the drive pulse generator 3 and drives the lower cathode of the display bar 10, and 8 is the output of the video signal converter 5. and an upper anode drive unit which receives the output of the drive pulse generator 3 and drives the upper anode of the display panel 10; 9 receives the output of the video signal converter 5 and the output of the drive pulse generator 3 and drives the display panel; This is a lower anode drive unit that drives the lower anode of 1o.

In FIG. 1, the operations up to the control signal generation section 4 and the video storage of the video signal conversion section 5 are similar to those of the conventional example.

The upper anode drive unit 8 and the lower anode drive unit 9 receive write pulses and sustain pulses from the drive pulse generator 3, and receive upper and lower display video signals from the video signal converter 5 to create an image in the gap between successive sustain pulses. An anode drive signal is created in which write pulses selected according to the signal exist. The upper cathode drive section 6 and the lower cathode drive section 7 receive a reset pulse, a scan pulse, an erase pulse, and a shift clock from the drive pulse generation section 3, and output them in a positional relationship with the horizontal axis as time shown in FIG. . In the output of the upper cathode drive section 6, a reset cathode signal is first applied to the upper and lower ends RC (display panel divided portion) of the display panel 10 to trigger the start of scanning, and then a scanning pulse and an erasing pulse are combined. A cathode drive signal is output that shifts upward from the display panel divided portion toward the top line of the panel at a horizontal period H. The lower cathode drive section 7 is shifted downward from the display panel divided portion toward the bottom line of the panel.

FIG. 3 shows how the display panel is driven by the operations described above, plotting time on the horizontal axis. In this figure, for comparison, (al) shows conventional progressive scanning, and (bl) shows simultaneous progressive scanning of two divided areas according to the present invention.

Further, FIG. 4 shows a comparison between the present invention (BL and conventional FA) in how data is read in the case of displaying an actual image.

Reading from the field memory of the video signal converter 5 is performed bit by bit at high speed, but the video signal for the upper display from the divided portion of the display panel IO to the top line of the screen is read as the video signal for the lower display. reads the upper and lower parts simultaneously from the 10-divided portion of the display panel to the bottom line of the screen.

Here, if the number of quantized bits of the video is k, the horizontal period is H, the number of lines is n%, and the vertical period V is represented by y the LSB display (maintenance) period, then the number of lines dividing the display panel is □
Therefore, the total display period Y for all the focuses is expressed as follows.

Comparing this equation with the conventional example (1), under the same conditions, the total display period is longer than in the conventional case, and the brightness can be improved.

〔Effect of the invention〕

As described above, according to the present invention, the display panel is divided into two at the center in the vertical direction, two drive circuits are provided, and one scans the display panel from the center toward the top. At the same time, the other side scans from the center of the display panel toward the bottom, so the display panel can be scanned simultaneously in parallel, and the display period (panel lighting period) can be lengthened. Therefore, there is an effect that the screen sharpness of the display panel can be improved.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a plasma display display system according to an embodiment of the present invention, FIG. 2 is a diagram of the display panel drive timing of the present invention, and FIG. 3 is a diagram showing the display timing of the present invention in comparison with the conventional one. 4 is a reference diagram for the video signal converter of the present invention and is shown in comparison with the conventional one, FIG. 5 is a configuration diagram of a conventional plasma display device, and FIG. 6 is a conventional display panel drive timing. This is a diagram. 3... Drive pulse generation section, -4... Control signal generation section, 5... Video signal conversion section, 6...
... Upper cathode drive section, 7 ... Lower cathode drive section, 8 ... Upper anode drive section, 9 ... Lower anode drive section, 10 ...・Display panel, UA, L
A: display anode, LIS, LS: scanning anode, C: cathode, RC: reset cathode. Agent Patent attorney Jun Miyazono - Figure 4 I L button ζa) Kamigori Yoshoyoyo O 6 Sun Moon (b'1 Procedural amendment (spontaneous) Heisei λ year end, month day 1, case indication patent application Heisei 2 No. 136151 No. 3, Relationship with the person making the amendment Patent applicant Address 2-2-3 Marunouchi, Chiyoda-ku, Tokyo Name (601) Mitsubishi Electric Corporation Representative Shiki
Moriya 4, agent address: 2-9-4-405 Iidabashi, Chiyoda-ku, Tokyo Drawings subject to amendment. Details of the amendment (1) The drawing and Figure 4 will be amended as shown in the attached sheet. Figure 4 Conventional (a) Lower divided part for upper anode (for p anode) Weight ≦ Sun/Moon (b)

Claims (1)

[Claims] The display panel includes a display panel in which electrodes are arranged in a matrix, and a drive circuit that drives one row of electrodes in the horizontal direction of the display panel. In a plasma display display method in which the image is displayed by sequentially scanning the display panel by moving to the next row in the vertical direction of the display panel and then sequentially scanning the display panel in the same manner, The plasma is divided, and the driving circuit is provided in two systems, one of which scans the display panel from the center toward the top, and at the same time, the other scans from the center of the display panel toward the bottom. Display method.