Effects of flicker characteristics from solid-state lighting on detection, acceptability and comfort

A study to assess the detection and acceptability of flicker and stroboscopic effects under different lighting conditions was conducted. Frequencies from 50 Hz to 300 Hz were assessed, as well as different modulation amounts, duty cycles, waveform shapes and correlated colour temperatures. For the range of conditions evaluated, direct perception of flicker was negligible at 100 Hz or higher, but stroboscopic effects could be perceived at 300 Hz. Reducing flicker modulation from 100% to 33% decreased perception of stroboscopic effects. A higher duty cycle was associated with slightly lower discomfort. The implications for solid-state lighting systems producing high-modulation flicker are discussed.