铁路灯光信号显示的一些研究

SOME EXPERIMENTS OF RAILWAY LIGHT SIGNAL DISPLAY

铁路色灯信号不论在白天或夜间都指挥着列车的运行,其显示好坏直接关系到列车的安全和效率。影响色灯信号显示的因素很多,如光源参数,光系统结构,灯光散角,天气好坏等。而色灯信号的颜色,观察距离(或视张角)以及亮对比度是人对信号识别的三个较重要因素,所以我们想从这三个方面来讨论信号灯光显示问题。

Several variables, i.e. colour, visual angle and brightness contrast that affect theefficiency of railway light signal display were investigated. About 1500 observers se-lected from various districts and nationalities participated in a colour naming experi-ment in which colour zones on the chromaticity diagram had been determined foruse as railway light signals. Two series of identification experiments were carried out at a railway yard. Inone series, visual angle was kept constant and brightness contrast was a variable. Inanother series brightness was kept coustant and visual angle was a. variable. In bothseries red, green and yellow signals were presented randomly. In the preliminary experiments it was found that while the red and yellow signalswere kept in favourable display conditions the observers showed higher probability ofcorrect identification for the green signal even if it was under unfavourable coudition,because if the signals were not red or yellow, it should have been green. After addinga white signal and a non-signal as interference to eliminated the guess effect, twosets of psychophysical functions ——correct identification rate vs. visual angle curveand correct identification rate vs. brightness contrast curve had been obtained.