JPS621381A - Video display terminal equipment - Google Patents

Abstract

PURPOSE:To relax the fatigue of user's eyes by controlling the degree of modulation of a luminance modulating circuit in accordance with the illuminance in a room to adjust the luminance of a cathode-ray tube to an optimum value. CONSTITUTION:When a changeover switch 15 is switched from the side of a luminance adjusting knob 11 to the side of a modulating circuit control means 14, a luminance control signal corresponding to the illuminance in the room is outputted from the modulating circuit control means 14 to a luminance modulating circuit 10. As the result, the picture signal inputted to the modulating circuit 10 on the basis of a graphic command from a host computer 1 has the luminance adjusted by said control signal to obtain the signal, whose luminance is automatically adjusted most suitably, on the screen of a cathode-ray tube 12. Thus, the user sees always the screen in the optimum luminance state independently of the variance of the illuminance in the room.

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a graphic computer connected to a computer.
This article also relates to video display terminal devices (hereinafter referred to as VDT devices) used for displays, word processors, etc.

[Conventional technology]

FIG. 3 shows a graphic display connected to a computer, which is a conventional VDT device of this kind, and (1) shows graphic commands based on a program to display a desired figure. The host computer to output, (4) is the graphic command processing procedure from this host computer +2113) 'S? Process this input graphics command to create the desired shape? This is a VDT device for display, consisting of the following:

(5) is a memory consisting of a ROM that stores command processing procedures; (61 receives graphic commands from the host computer, reads the memorized command processing procedures, and executes the commands; A channel processor (8) converts the command procedure 7 into a machine instruction code and outputs it to the data buffer (7).
The segment memory t+91a in which data to be displayed is stored is a display processor that processes based on the instructions of the machine instruction code inputted through the data buffer (7). It stores data to be displayed and outputs an image signal consisting of data stored in this segment memo (January 8) or graphic data sent from the host computer (1). ! 10 is a brightness modulation circuit that receives this image signal and adjusts its brightness (strength of contrast between the background screen and displayed characters when displayed on the screen), and αυ is a brightness modulation circuit for controlling the modulation degree of this brightness modulation circuit. A brightness adjustment knob a2 for outputting a control signal is a cathode ray tube that receives a brightness-adjusted image signal from the brightness modulation circuit α and displays a desired image on the screen.

In the ThT device configured in this way, the host computer (υ) processes the graphic code based on the graphic code and displays the desired figure on the cathode ray tube α2.
This is what is displayed on the screen.

The brightness on the screen is adjusted by the brightness modulation circuit tllY14 by manually adjusting the brightness adjustment knob aυ.

[Problem that the invention seeks to solve]

However, in a nine VDT device configured in this way, 1
Brightness adjustment on screen? This has to be done manually using the brightness adjustment knob, and even if the indoor illuminance changes during use, it is difficult to adjust the brightness, so it is easy to neglect the adjustment and end up using the screen with inappropriate screen brightness. I was worried that this would increase eye fatigue.

This invention has been made in view of the above-mentioned points, and an object thereof is to provide a video display terminal device which can be used with an appropriate screen brightness at all times by adjusting the brightness on the screen according to the indoor illuminance. It's something.

[Means for solving problems]

The video display terminal device according to the present invention is provided with a modulation circuit control means for detecting indoor illuminance and controlling the modulation degree of the brightness modulation circuit according to the detected indoor illuminance.

[Effect]

In this invention, the modulation circuit control means detects the indoor illuminance and controls the modulation degree of the brightness modulation circuit.

Screen brightness on cathode ray tube screen? It is better to adjust it to the appropriate condition.

〔Example〕

An embodiment of the present invention will be explained below based on FIGS. 1 and 2. As shown in FIG. Modulation degree of modulation circuit? A modulation circuit control means for controlling a second
As shown in the figure, a photodetecting element αG such as a thermistor thermometer that converts the intensity (brightness) of light into a current value, an amplifier 11η that amplifies the current value from this photodetecting element 1, and this amplifier (11 The brightness set circuit +II outputs a control signal according to the current value from the cathode ray tube a.The brightness set circuit +II outputs a control signal according to the current value from the cathode ray tube Find the correspondence with the appropriate brightness value that minimizes eye fatigue on the 'tt screen, and output a control signal to control the modulation degree of the brightness modulation circuit using the current value from the amplifier αa according to this correspondence. As is a changeover switch for switching the control signal from the modulation circuit control means a# and the control signal from the brightness vI4 adjustment knob αD to the brightness modulation circuit.

In the VDT device configured in this way, a changeover switch (151Y modulation circuit control means IIIK) is used to control the brightness y! on the screen of the cathode ray tube tta according to the indoor illuminance. The brightness modulation circuit αIK is output from the modulation circuit control means α◆.Therefore, the image signal input to the brightness modulation circuit based on the graphic command from the host computer (!) is adjusted in brightness by the nine control signals described above, and is converted into a cathode ray. Since the image is input to the cathode ray tube (13), an image whose brightness is automatically adjusted to suit the VC1lk can be obtained on the screen of the cathode ray tube (13). The screen of the cathode ray tube a2 can always be viewed at optimal brightness, which alleviates eye fatigue.

If you set the changeover switch (l!1) to the brightness adjustment knob aυ side, you can adjust the brightness on the screen of the cathode ray tube housing 2 by manually adjusting the brightness adjustment knob 0υ, similar to the one in Figure 3 above. It is something that can be done.

〔Effect of the invention〕

As described above, the present invention is based on a modulation circuit control means that detects indoor illuminance and controls the modulation degree of a brightness modulation circuit according to the detected indoor illuminance. Since this is provided, the brightness on the screen of the cathode ray tube α2 is automatically adjusted to the optimum value regardless of the indoor illuminance.

This has the effect of alleviating eye fatigue of the user.

[Brief explanation of drawings]

Are Figures 1 and 2 an example of this invention? Fig. 1 is an overall configuration diagram of the VDT device, Fig. 2 is a block diagram showing the Rii #1 circuit control means, and Fig. 3 is a diagram of a conventional VDT device.
! - is an overall configuration diagram shown. In the figures (11 is the brightness modulation circuit, σ2 is the cathode ray tube, Q41 is the modulation circuit control means. In each figure, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] A device equipped with a brightness modulation circuit that receives an image signal, adjusts its brightness, and outputs the brightness-adjusted image signal to a cathode ray tube, detects indoor illuminance, and performs the brightness modulation according to the detected indoor illuminance. A video display terminal device comprising a modulation circuit control means for controlling the modulation degree of the circuit.