Relation between photometric characteristics of various VDTs and eye fatigue

本研究的目的是开发一种分析不同类型VDR屏幕以下特性的方法。1)VDT屏幕上字符的清晰度和抖动。2)VDT屏幕上形成字母的亮度的振荡。3)VDT屏幕上亮度光谱的时程。为了评价其清晰度和抖动，采用模块化的面阵摄像机、控制器、视频监视器和带CRT显示器的PC机组成了测量系统。利用该系统获得并分析了每帧字符等亮度的轮廓线。为了评价光谱的振荡性和时程，利用光纤器件、单色仪、光电倍增管、放大器和带有模拟信号处理器的个人计算机开发了测量系统。在实验室研究中，对不同厂家的不同型号的VDT进行了上述指标的测量。

The aim of the study was to develop the method to analyze the following characteristics of various type of VDRs' screen. 1)Sharpness and trembling of characters on a VDT screen. 2) Oscilation of the luminance forming letters on a VDT screen. 3) Time course of the spectrum of the luminance on a VDT screen. In order to evaluate the sharpness and trembling, measureing system was developed with modular area camera, controller, video monitor and personal computer with CRT display. By using this system the contour lines for equal luminance for a character of each frame were got and analyzed.In order to evaluate the cscillation and the time course of the spectrum, a measuring system was developed with optical fiber devices, monochrometer, photomultiplier, amplifier and personal computer with analoz signal processor.In the laboratory studies, the above indexes were measured for various VDT types from different makes.