JPS59155888A - 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 Application of the Invention] The present invention relates to an improvement in a display device using a cathode ray tube.

[Prior art]

A cathode ray tube (hereinafter referred to as C141') is generally used to display data from a computer or a device with a built-in computer.
is used, but in this case, the same font will be displayed repeatedly in the same place. As a result, if the phosphor is used for a long time, coloring traces remain after the electron beam irradiation to the phosphor is stopped, and after 5,000 hours or more, this phenomenon becomes noticeable and the display performance deteriorates. That is, display devices such as computers have the disadvantage that traces of frequently displayed content remain when the next content is displayed, making the displayed content difficult to read.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the drawbacks of the above-mentioned prior art and to provide a display device whose display performance does not deteriorate even when used for a long time.

[Summary of the invention]

A feature of the present invention is that it is configured by providing a control section that has a function of slightly moving the display position of the cathode ray tube every time the display is switched.

[Embodiments of the invention]

FIG. 1 is a system diagram of a display device that is an embodiment of the present invention. 1 is a CRT, 2 is an input section, and 3 is a keyboard of the input section 2. These are connection lines 4a.

4b, it is connected to the control section 5 to constitute a display device. The CRT1 is capable of displaying, for example, 25 lines of 40 characters, and the keyboard 3 includes keys for inputting numbers, letters, etc., control keys for switching display contents, and the like. The control unit 5 controls the characters and characters displayed on the microcomputer in the main body and the CRTl of the display device.
- Consists of an interface for transmitting numbers, etc., and an interface for receiving data input from the input section 2. For example, when a key on the keyboard 3 is pressed, a code unique to that key is transmitted to the control unit 5 as input data.

FIG. 2 is a block diagram of the control section of FIG. 1, showing the configuration of an interface for transmitting characters, numbers, etc. to the microcomputer 6 and C1-ITl. Microcomputer lJ: (, The content to be displayed on the RTi is output to the storage device 7, which is a 16 kilobyte RAM, and the storage device 7 can store all the fonts of characters, numbers, etc. to be displayed.

There is a certain relationship between the address of the RAM in the storage device 7 and the display position of characters, numbers, etc. displayed on the CRTI, and unless the horizontal synchronization signal 12 or vertical synchronization signal 13, which will be described later, is changed, they will be stored at the same address. The characters and numbers shown are CRT
displayed at the same position on l.

Mata, the microcomputer 6 sends cg'ri to the controller 8.
Outputs various parameters to control. The controller 8 sends three types of signals to the video controller 9 based on various parameters for controlling the CRTI sent from the computer 6. That is, a display timing signal 11, a horizontal synchronization signal 12, and a vertical synchronization signal 13.

The video controller 9 is the signal and storage device 7 of the three buildings mentioned above.
The contents of fonts such as display characters stored in the video signal are converted into video signals (and transmitted to the RTI).

Note that 10 is a clock generator, and the controller 8 uses the clock signal to generate a signal.

FIG. 3 is a diagram showing the waveform of a signal transmitted from the controller in FIG. 2. The display timing signal 11 indicates the image display period of horizontal and vertical scanning, and the video controller 9 controls the CRT only during the period when this signal is at HIGH level.
Send the video signal to l. Horizontal synchronization signal 12 is CRT
This is a signal for applying horizontal synchronization to CRTl, and in synchronization with this, CRTl performs horizontal scanning. Also, vertical synchronization signal 1
3 is a signal to apply vertical synchronization to CR and TI. In synchronization with this, CRTl performs vertical scanning. That is, by changing the information content sent from the microcomputer 6 to the controller 8, the horizontal synchronization signal is 12 and vertical synchronization signal 13 can be changed.

When the output position of the horizontal synchronization signal 12 is delayed, CR'1'1
The display position of the CRT1 is shifted to the left by 7], and when the output position of the horizontal synchronizing signal 12 is advanced, the display position of the CRT1 is shifted to the right. CR occurs when the output position of the vertical synchronization signal 13 is delayed.
The display position on Tl is shifted upward, and the vertical synchronization signal 1
When the output position of 3 is advanced, the display position on the CRTl shifts downward.

These situations are respectively illustrated in the lower half of FIG.

Using the above properties, deterioration of the CRTI phosphor screen is prevented as follows.

When the input code of the key to switch the display contents is sent from the keyboard 3 to the control unit 5, the microcomputer 6 clears all fonts such as fonts such as low-indication characters stored in the RAM in the storage device 7, and Clear all displayed contents. Next, the microcomputer 6 changes and outputs the values of various parameters for controlling the CRT1 to the control section 8. By changing this parameter, the timing of one or both of the horizontal synchronization signal 12 and the vertical synchronization signal 13 among the signals transmitted from the controller 8 to the video controller 9 is changed.

Thereafter, the microcomputer 6 stores R in the storage device 7,
Outputs a new phant signal (such as letters and numbers to be displayed on RTl) to AM, and displays the new content on CRTI.
L. At that time, the timing of one or both of the horizontal synchronizing signal 12 and the vertical synchronizing signal 13 is changed, and the display position of the CRT1 is moved.

Keyboard 3 is used for input to switch the display contents for this kind of control.
CR'I' 1 by doing this every time there is an input
Since the upper display position changes and only the phosphor at the same location on the CRTl can be prevented from changing its luminescence, the life of the phosphor is extended. However, if the movement of the display position is too large, you will feel the movement of the display position every time you change the displayed content, so in reality the movement of the display position in the horizontal direction is 1/2.
It is desirable that the movement of the display position in the vertical direction be about 1 character and about 1 to 8 scanning lines.

In the display device of this embodiment, data from a manual section with a keyboard is connected to a CRT via a control section, and within the control section, the output of a microcomputer is supplied to a controller and a storage device, and the display position is controlled by a video controller. By generating a moving signal, the display position of the CRT is slightly moved so that the display is always displayed at a new position. Therefore, it is possible to maintain the JtT phosphor screen in a high-performance state for a long period of time.3 Although the above embodiment describes the case where the keyboard 3 is used in the input section 2, it is possible to maintain the JtT phosphor screen in a high-performance state for a long period of time. Similar effects can be obtained with switches and other input devices.Also, the number of characters displayed on a CRTl is 40 characters x 2-5.
It can be easily inferred that similar effects can be obtained even in cases other than rows and in cases where graph display is performed. Furthermore, each time the display contents are changed, the microcomputer writes a new C
A similar effect can be obtained by using or combining a method of changing the storage address of characters, numbers, etc. displayed on the RTl.

〔Effect of the invention〕

Since the display device of the present invention can minutely move the display position of the CRT when switching the display, it has the effect of extending the life of the display device and providing suitable display for a long period of time.

[Brief explanation of the drawing]

Fig. 1 is a system diagram of a display device that is an embodiment of the present invention, Fig. 2 is a block diagram of the control unit shown in Fig. 1, and Fig. 3 shows the waveform of a signal transmitted from the controller shown in Fig. 2. It is a line diagram. DESCRIPTION OF SYMBOLS 1...CRT, 2...Input unit, 3...Keyboard, 4...Connection line, 5...Control unit, 6...Microcomputer, 7...Storage device, 8...・Controller, 9
...Video controller, 10...Clock generator, 11...Display timing signal, 12...Horizontal synchronization signal, 13...Vertical synchronization $1, 2, 5, 3 flashes

Claims (1)

[Claims] 1. A display device that displays a repeating font or the like on a cathode M'W, characterized in that it includes a control section that has a function of slightly moving the display position of the cathode ray tube each time the display is switched. Device.