Study on fluorescent lamp illumination and flicker

It is necessary completely to study and appraise characteristics of fluorescent lamp illumination. Flicker index is an important appraisal item. The fundamental frequency of flicker is twice as high as power frequency. The flicker index by electromagnetic ballast is more than 10%, and it is increasing sharply as reducing power voltage or illumination. By electronic ballast, especially one with active power factor correction, the lamp can run nearly without flicker under wide range of AC power voltage variation.