Thursday, May 2025
05:00 PM - 08:00 PM
Room: 220A
Session: Applied Vision Posters
Influence of Evening Display Light on Melatonin Levels and Autonomic Nervous System Balance
Description:
In this study, we compared the effects of light from liquid crystal display (LCD) and organic light-emitting diodes (OLED) televisions (TVs) on humans by measuring the saliva melatonin levels and the heart rate variability (HRV) during and before/after watching TV in the evening with 40 volunteers. Participants using LCD TV demonstrated a decreased melatonin secretion by 2.7% after watching TV, whereas those utilizing OLED TV exhibited an increase of 8.1%. The HRV analysis, which represents the relative activation levels of the sympathetic and parasympathetic nerves, revealed that on average, OLED TVs activated the parasympathetic nerves more than LCD TVs during the entire watching time. This indicates that watching OLED TVs induces relatively comfortable states. Further, a questionnaire was simultaneously conducted to assess eye discomfort and overall eye strain after watching TV, and the results showed a significantly increased eye fatigue after watching LCD TV compared to OLED TV.