Abstract
Light output of the ordinary discharge lamps operating on A. C. power supply shows cyclic variation similar to A. C. input power, and whose frequency is twice of the A. C. input power.
This variation of light output is called “FLICKER”.“FLICKER INDEX” and “PERCENT FLICKER” have been proposed as ideas to evaluate the flicker of light sources. However, they cannot offen accurate evaluation of the flicker, because actual sensibility to the human eye may differ even if they have the same numerical values of evaluation measured under the same measuring conditions.
To increase accuracy of evaluation, “FLICKER BY DISTORTED WAVE” is introduced as new concept. This new method of evaluation is realized by checking the lower harmonic component after harmonic analysis of light output applying “FOURIER SERIES”.
We recognize through our repeated experiments that the results evaluated by this “FLICKER BY DISORTED WAVE” are conformed to actual sensibility of flicker.