Abstract
Light-emitting diode (LED) lights are expected to improve the visibility of emergency vehicles. We propose a two-stage method for evaluating the flash patterns of LED warning lights. In the first stage, we identify the visibility of many kinds of flash patterns using the mental measure of “distinctness” from Scheffe's paired comparison. In the second stage, we select a few kinds of flickering patterns with higher distinctness out of patterns used in the first stage, and obtain the reaction time to their patterns with high accuracy. We conducted experiments on 3DCG simulation by creating CG animations as stimuli in which LED lights flicker in various patterns. The results of the two-stage evaluation using 11 flash patterns indicated that the mental measure of distinctness of the LED flickering patterns is correlated to reaction time. We propose that the most-visible flickering pattern can be designed using this method.
