A portable automatic measuring apparatus of the critical flicker frequency with magnetic tape recording

Abstract

An automatic measuring apparatus has been worked up for the critical flicker fusion frequency measurement which is widely applied in ergonomic evaluation studies. Because the sector-type flicker testers are liable to cause unreliable readings due to vibration, changes in illumination, inaccurate calibration or direct readings of the dial, the new type makes use of a photogenic diode whose frequency of flash signals automatically varies in accordance with the subject's responses. The subject is to reset the apparatus and push the response key in finding the flickering of the signal light the intermittent frequency of which linearly decreased each time from the above-threshold level, no testing persons being necessary. The power source is automatically set off when the subject has responded five times. The measurement can either be read on a digital display or printed afterwards by means of a magnetic tape recorder and a digital printer. The apparatus is portable having a direct current power supply. Its application possibility seems large in many fields of ergonomics.