JPS6172292A - Crt 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 [Technical Field of the Invention] The present invention relates to a CRT display device that digitally displays alphanumeric characters, line segments, etc. on a CRT.

[Conventional technology]

Figure 1 shows part of the sieve surface signal generation circuit of a conventional CRT display device. In the figure, (1) is coordinate data, (2) is a state set pulse, (3) is a register, and (4) is a D
/A converter, (5) is a deflection signal, (6) is a state set pulse delay circuit, and (7) is the next state set pulse.

Next, the operation will be explained. The coordinate data (υ) is read into the register (3) at the timing of the state set pulse (2). This data is converted into an analog quantity by the D/A converter (4) and sent to the deflection system as a deflection signal (5). Also, the state set pulse (2) is delayed by the delay circuit (6) for the time necessary for the electron beam of the CRT to move to the specified position, and sets the next state as the next state set pulse.Thereby, Moving to the next state, the alphanumeric character generation circuit is activated and alphanumeric characters are displayed at the specified coordinates.

Since the conventional CRT display device is constructed as described above, it has the disadvantage that it requires a certain amount of time to move the coordinates regardless of the distance traveled.

[Summary of the invention]

This invention was developed to eliminate the drawbacks of the conventional ones as described above, and by calculating the moving distance between coordinates, it is possible to predict the settling time of the electron beam and eliminate the need for waiting time for the next state. The object of the present invention is to provide a CRT display device that minimizes display processing time and requires less display processing time.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. Second
In the figures, the same reference numerals as in FIG. 1 indicate the same or equivalent parts. Also, (8) is the X system coordinate data, (9) is the Y system coordinate data, αQ is a subtracter that calculates the displacement of each of the X and Y systems, and the mouth is the subtractor that calculates the amount of coordinate movement.Δl=V/CΔX)2+
(ΔY)2 calculator, (2) is the enlargement/reduction ratio of the CRT screen, the delay circuit delays the state set pulse by a time proportional to Δl according to the enlargement/reduction ratio of the screen, a< is the X deflection signal , (to) is the Y deflection signal.

Next, the operation will be explained. X system coordinate data (8), Y
The coordinate data (9) is latched into each of the two stages of registers (3) at the timing of the state set pulse (2).

In the first display, since the immediately preceding coordinate data is unknown, the delay circuit (to) delays it for a specified time, outputs the next state set pulse (7), and displays alphanumeric characters, etc. in the next state. From the second onwards, every time the state set pulse (2) is input, the difference from the previous data is calculated by the subtractor αq, and the difference is calculated by the subtractor αq. A calculator αη calculates the coordinate difference in the xy coordinate system. Here, the enlargement/reduction ratio (value) is taken in, the enlargement/reduction ratio XΔl is obtained, and the position difference on the CRT screen is calculated. Delay circuit (2)
gives the state set pulse (2) a delay time proportional to the output of the Δl calculator (IIJ) and outputs the next state set pulse (7).As a result, when the output of the Δl calculator (2) is small, the next state can be set in a short time. When the pulse (7) is output and the enlargement/reduction ratio increases, the output of the Δe calculator 017 increases and the next state set pulse is delayed by a time that covers the settling of the electron beam.

In the above embodiment, the enlargement/reduction ratio (b) is input to the mura calculator Qη, but it may also be input to the delay circuit Q3.
Furthermore, the delay circuit does not mean a delay element, but may be any circuit configuration for the purpose of delay, such as a counter or a shift register.

〔Effect of the invention〕

As described above, according to the present invention, since the waiting time of the electron beam movement time can be dynamically changed, the idle time can be minimized and the display capability of the display device can be improved.

[Brief explanation of the drawing]

Figure 1 shows one of the deflection signal generation circuits of a conventional CRT display device.
FIG.
FIG. 3 is a circuit diagram showing a part of the deflection signal generation circuit of the RT display device. In the figure, (1) is coordinate data, (2) is state set pulse, (3) is register, (4) is D/A converter, (5) is deflection signal, (6) is delay circuit, (7) is the next state set pulse, (8) is the X system coordinate data, (
9) is Y system coordinate data, Oq is a subtracter, (b) is a calculator, (6) is an expansion/reduction ratio, side is a delay circuit, a< is X
The deflection signal (A) shows the Y deflection signal. In the figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] In a random scan type display device using CRT,
A CRT display device, characterized in that a beam movement distance calculation circuit is added for reducing the settling wait time of an electron beam to the time necessary for beam movement between display coordinates.