Reduction of flicker of light sources is one of the important factors for comfort lighting. Reduction of flicker of light sources seen directly, for example portable desk standards mounted with a fluorescent lamp is very important. Especially, flicker sensation is more from alternate diferent light waves such as the flicker of the both parts of the fluorescent lamp.
At first, the experiments containing subijective appraisals were made, in order to choose the most relevant index from the conventional indexes such as the Flicker Index.
As a result, it was found that relations between respective indexes and flicker sensation from the flickering light were not sufficient.
In the second place, as a new provisional index, the ratio of the two average luminances of the alternating light waves that were divided by the respective wave durations has been propesed and confirmed that this index has sufficient relation to flicker sensation through the experiments of subjective appraisals.
This has been named “Flicker Luminance Ratio”.
At last, experiments of subjective appraisals were made to find out the practical limit of flicker sensation of the portable desk standardes quantitatively using the “Flicker Luminance Ratio”.
For the design objective of the desk standard, 0.92 has been determined to be proper for 50 Hz light waves.
View full abstract