Effects of temporal light modulation on visual task performance in different modulation frequencies

Abstract

This study investigated the impact of temporal light modulation (TLM) generated by light-emitting diode lighting on visual task performance. Five lighting conditions were used in this study. One was a direct current, and the other four used pulse-width modulation with 60 Hz, 100 Hz, 400 Hz and 1000 Hz modulation frequencies, respectively. The study assessed participants’ performance in various visual tasks involving eye movements, including arithmetic problem-solving, linking numbers tasks and the CamBlobs™ Contrast Sensitivity test. The experimental results showed that the response time of visual tasks related to typical daily eye movements, such as the arithmetic problem-solving task and the CamBlobs™ Contrast Sensitivity task, were in proportion to the P_st^LM, which showed the influence of flicker. In contrast, the linking numbers task, which required more extensive eye movements and object movements, was more relevant to the stroboscopic visibility measure than ${\mathrm{P}}_{\mathrm{st}}^{\mathrm{LM}}$ , which showed a higher influence of stroboscopic effect than flicker. These findings underscore the significance of considering TLM parameters when designing lighting systems for environments where visual tasks are crucial. This research contributes to our understanding of how light modulation affects human performance in visually demanding settings and has implications for optimising lighting design to enhance task performance.