JPS61175680A - Display unit - Google Patents

Abstract

(57) [Summary] 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 display device that displays graphics, etc., and particularly relates to an improvement of a rask scan type display device.

2. Description of the Related Art In recent years, computer-aided design systems (hereinafter referred to as CAD) that perform design while talking to a display device have become popular, but increasingly high-definition display screens are required.

The display method of the rask scan type CR, T display device is the so-called raster scan method, which is well known for televisions, etc., in which CRT electron beams are scanned and displayed by brightness modulation. Scan 'a' for screen display
<raster) number is increasing.

However, in the above method, further increasing the number of scanning lines within the range of repetition frequencies that do not cause flickering requires an increase in deflection power, video frequency, etc., and there is a cost limit, for example, 60 cycles. For the return frequency,
The number of scanning lines per screen is said to be limited to about 1000.

On the other hand, a display screen used for CAD etc. has an area for displaying figures as well as a menu for designing the figures.

There is an area for displaying messages, etc., and the same scanning lines as in the graphic display area are used in this area, even though high-definition display is not required.

Therefore, there is a demand for an economical display device that can effectively increase at least the resolution (number of scanning lines per unit length) of the graphic display area.

[Conventional technology]

The conventional technology will be explained below.

FIG. 2(a) is a block diagram of a CRT display device driving section, and FIG. 2(b) is a diagram illustrating a scanning method.

In Figure 2+a), 1 is a CRT, 2 is a horizontal coil,
3 is a vertical coil, 4 is a refresh memory section, 5 is a synchronizing signal generating section, 6 is a vertical scanning signal generating section that generates a vertical scanning signal that is a sawtooth wave with a constant scanning speed, and 7 is a generating section that generates a similar horizontal scanning signal. This is a horizontal scanning signal generating section that generates horizontal scanning signals.

As mentioned above, in CAD, etc., the figure display area A.

Although it is divided into character display areas B, each dot information is stored in the corresponding area of the refresh memory section 4.

The scanning is performed using a horizontal scanning signal 100 generated according to a synchronization signal;
By passing the vertical scanning signal 101 through the horizontal coil 2 and vertical coil 3, scanning is performed uniformly on the entire screen as shown by the arrows in the figure.

In synchronization with the above scanning, dot information is scanned and read out from the refresh memory section 4, and the dot information is displayed after being subjected to brightness modulation.

As a result of the above, both the graphic display area A and the character display area B are displayed at the same resolution.

The above scanning is performed at a constant repetition frequency as shown in FIG. 2(b), and the vertical repetition frequency Fv is usually 60.
Cycle (Tv=16.7m5), horizontal repetition frequency F
h is 60 cycles (Th = 16.7 μs), assuming the number of scanning lines of one screen (number of horizontal scans per vertical scan) is 1000.
).

[Problem that the invention seeks to solve]

High-definition figures, that is, displays with high resolution, can be obtained by increasing the horizontal repetition frequency Fh relative to the vertical repetition frequency Fv, but this is limited by scanning power, video frequency, etc., and is not practical. However, the upper limit is set at the number of scanning lines mentioned above, and there is a problem in that the cost increases rapidly in response to demands for higher definition.

[Means for solving problems]

The above-mentioned conventional problems are solved by the display device of the present invention, which includes a horizontal scanning drive means with a predetermined repetition frequency and a vertical scanning drive means with a predetermined repetition frequency and a different scanning speed for each display area. Can be done.

[Effect]

That is, if the horizontal repetition frequency is constant and the vertical scanning speed is slowed, the number of scanning lines per unit length, that is, the resolution increases, and conversely, if the vertical scanning speed is increased, the resolution decreases. Therefore, even if the horizontal and vertical repetition frequencies are the same as before, if you increase the vertical scanning speed and reduce the resolution in an area that requires low resolution, you can slow down the vertical scanning speed in areas that require that extra resolution. .

Therefore, the resolution of the graphic display area can be improved without increasing the horizontal repetition frequency and video frequency.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1(a) is a block diagram of a CRT display device driving section, and FIG. 1(b) is a diagram illustrating an embodiment of the scanning method of the present invention.

In FIG. 1(b), reference numeral 10 denotes a display screen in which the horizontal and vertical directions are reversed, on which equally spaced scanning lines 103 scanned by the same vertical scanning signal 101 as in the conventional art are drawn; is scanned by the vertical scanning signal 105 of the present invention and has scanning lines 10 at different intervals in areas A and B.
4, showing that scanning is performed in the X and Y directions.

Note that the horizontal scanning signal 100 is the same as the conventional one.

In the figure, M, O, and N represent current values, and these current values, vertical amplitudes m, o, and n, and the number of horizontal scanning lines a, respectively.

c and b correspond.

Reference numeral 105 shows the waveform of the vertical scanning signal of the present invention, in which the time TI required to scan area A is compared with that of the conventional one (
The scanning speed is made larger than Tlo) to slow down the scanning speed, and at the time T2 when area B is scanned, the scanning speed is made faster (to match the conventional scanning time TV for one screen).

That is, if the time required to reach the current N required to scan area A is TI>Tlo, then the number of horizontal scanning lines in area A is b
Increases to C. The vertical amplitudes are both n, so the resolution increases from b/m to 07m.

In addition, in area B, the number of horizontal scans of conventional a-c lines is
The resolution decreases as the image expands.

As described above, even if the vertical and horizontal repetition frequencies are the same as in the conventional technique, high-resolution areas can be provided by changing the vertical scanning speed depending on the area.

FIG. 1(a) shows the driving section of the CRT display device according to the embodiment of the present invention, in which reference numeral 12 denotes a refresh memory section;
13 is a synchronizing signal generating section, 14 is a first vertical scanning signal generating section, 15 is a second vertical scanning signal generating section, 16 is a combining section, and the same symbols as in FIG. 2 represent the same functions.

The first vertical scanning signal generating section 14 repeatedly generates the waveform of the part 105a that scans the area A in the vertical scanning signal waveform 105 shown in FIG.
Reference numeral 5 repeatedly generates a waveform of a portion 105b for scanning area B, and a synchronizing signal generating section 13 generates a synchronizing signal necessary for generating these waveforms and horizontal scanning signals.

The synthesizing section 16 is the first. Second vertical scanning signal generator 14.15
In addition to combining the outputs of horizontal and vertical coils 2 and 3,
to drive.

As described above, the resolution can be changed by changing the scanning speed of the display area, but it is not particularly limited to two areas, and can easily be realized even with a plurality of areas.

Note that in the above description, line scanning is referred to as horizontal scanning, and frame scanning is referred to as vertical scanning, according to common usage, and does not mean horizontal or vertical with respect to the display screen.

〔Effect of the invention〕

As explained above, according to the present invention, a high-resolution display area and a low-resolution display area are provided by controlling the vertical scanning speed. Resolution can be easily improved.

[Brief explanation of the drawing]

FIG. 1 (al is a block diagram of a CRT display device driving section of the embodiment, FIG. 1(b) is a diagram illustrating the scanning method of the present invention, and FIG. 2 (al is a block diagram of a conventional CRT display device driving section. 2(b) is a diagram explaining the conventional scanning method. In the figure, 1 is a CRT, 2 is a horizontal coil, 3 is a vertical coil, 7 is a horizontal scanning signal generator, and 12 is a refresh memory. , 13 is a synchronizing signal generating section, 14 is a first vertical scanning signal generating section, 15 is a second vertical scanning signal generating section, 16 is a combining section, 105 is a vertical scanning signal of the present invention, 105a is a vertical scanning signal for scanning area A The scanning signal, 105b, is a vertical scanning signal that scans area B. Explanation diagram of the attack method with 1 shame, 7-7 attack rate of 20 (20%)

Claims (1)

[Claims] A display device having a plurality of display areas, characterized by comprising horizontal scanning drive means with a predetermined repetition frequency and vertical scanning drive means with a predetermined repetition frequency and a different scanning speed for each display area. display device.