JPS58129471A - Raster scan system - 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 The present invention relates to an improvement in a raster scan type display of a TV mixed mode display in a general purpose graphic optical display and radar control system.

A general VC'l'V raster scan method is used for display devices that display images under certain bright environmental conditions. Increasing the number of scan lines to improve display quality in the Laser-rescan system and doubling the digital display capacity for TV mixed mode displays in the R-V system have recently received particular attention. There is. What is Vc's 'i' V mix mode display?
During the raster scan, the radar video is displayed, and the vertical retrace time of the raster scan is used to select a mode for displaying digital data using a random access method.

One basic solution to the above requirements is to increase the speed of each horizontal scanning line, but there is a speed limit in the case of electromagnetic deflection, and increasing the speed has the opposite effect of decreasing brightness. It's not easy because it's difficult. In conventional TV-type raster scanning, when performing horizontal scanning as shown in Figure 1, a horizontal retrace line H is required because it always scans from left to right. It's a waste of time. This water XP-N! Mori is a necessary function when an interface standard is required for a general broadcasting system, but it is not necessarily an essential function in a local Rose system. In the figure, V indicates a vertical blanking line.

The present invention eliminates one horizontal IFIlr line, that is, the horizontal retrace time, by scanning the raster scan horizontally in a U-shape, increasing the number of horizontal scanning lines for the purpose of high resolution, and improving TV mix in radar control. - The purpose is to lengthen the vertical return stroke in the mode, thereby making it possible to double the digital display capacity i.

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

In the present invention, as shown in FIG. 2, the two-star scan is reversed horizontally into a C'+ shape. As a result, there is no time for horizontal scanning, so it is possible to increase the number of horizontal scanning lines within a single time period (in the same frame). Furthermore, if the number of scanning lines is the same in the 1'' mix mode display in radar control, the vertical retrace time can be increased, and the digital display valley amount can be doubled.

When performing U-shaped horizontal scanning, the direction of deflection is alternately 18
In order to absorb the problem of inertia of the deflection thread that occurs when the deflection is reversed by 0°, a digital scanning method is adopted as shown in Figure 3. After returning two clock widths, the next horizontal scan (effective scan) is started with the effective scan, sound, and direction system in a stable state.

During this time, the brightness is blanked. If this is used in combination with the development of L high-brightness CRTs and the development of high-speed table deflection systems, even higher quality display devices can be realized.

Referring to FIG. 4, which shows a configuration diagram of an embodiment of the present invention, R
OM (Read 0nly Memory) 12th
The absolute values of the coordinates in the X direction of the U-shaped horizontal scan shown in FIGS. 3 and 3 are divided into n parts and stored in digital quantities. Timing synchronization is achieved by the clock generator 15, ROM addresses are generated one after another by the X-direction ROM address generator 13, and the contents of the corresponding addresses are read out by the encoder 11. The extracted X-direction absolute coordinate data 101 is sent to the D/A converter 21. Deflection in the X direction is performed through a deflection amplifier 22 and a deflection yoke 23. From the end of the horizontal scanning deflection to the next horizontal 71: start of scanning, the countermeasures are as shown in Fig. 3. As shown in FIG.
If the brightness flank instruction bit is set in the data stored in the MK and read out, the pit is decoded by the decoder 11, and the signal 103 is sent to the BLANK/
EJN Bl, ANK The brightness is blanked until the start of the next horizontal scan.

On the other hand, the coordinates in the Y direction are indicated by the Y direction coordinate generating section 14. This is carried out by creating a value 102 by subtracting ΔY in order to move the horizontal scan down one step every time n clocks +1 to 2 are counted. When one frame V is completed, it returns to the position of the first Y coordinate.

The digital value 102 of the Y coordinate is the same as the X system deflection system (D/
A converter 24. Deflection amplifier 25. Deflection in the Y direction is performed through the deflection yoke 26. 28 is a CRT.

In this way, a U-shaped raster scan can be realized, and the resolution can be increased by dividing the number of scanning lines within the same frame time, and the digital display capacity can be increased by increasing the vertical retrace time of a TV mixed mode display device. Doubling (increase) is possible.

As described above, the present invention eliminates the time equivalent to the horizontal retrace time by scanning in a U-shape in raster scanning, and uses the time saved to increase the number of scanning lines to increase the number of scan lines. When the same number of scanning lines is temporarily rectangular in the TV mix display for radar control and the effect of realizing resolution disfluency, the vertical retrace time can be lengthened, so that the digital display capacity can be doubled.

This is not based on increasing the horizontal scanning speed, so there is no deterioration in brightness.

[Brief explanation of the drawings] Figure 1 is a diagram of the conventional l'V two star scan system, the second one is a diagram of the U-shaped raster Φ scan system, and Figure 3 is the diagram of the end of the U-shaped horizontal scan. FIG. 124 is a circuit diagram showing an embodiment of the present invention in a partial block diagram. 11... Decoder and register, 12...
...ROM (Read only memory),
13...X-direction ROM address generation section, 14.
...Y direction coordinate generation section, 15...Clock generation section, 21, 24...X/YD/A
Coy bar p, 22, 25-...X/Y
% direction tINhG, 23.26...X/Y deflection yoke, 27...BLANK/LIN)sLA
NKj-Yotoichiri Mko, 28...CR,
T 0 grass 1 round 2 figure

Claims (1)

[Claims] (1) A raster scan method characterized by eliminating horizontal blanking and horizontal retrace time by repeating horizontal scanning in a U-shape. (21!!!) A raster scan method according to claim (1), characterized in that a predetermined scan period at the end and beginning of each horizontal scan deflection is an invalid scan.