International Lighting Healthy Eye Fatigue Relief Technology White Paper

ABSTRACT

Visual fatigue has emerged as a significant public health concern in the digital era, exacerbated by prolonged exposure to electronic screens and suboptimal lighting conditions. This review synthesizes current research on the etiology, epidemiology, and technological interventions for visual fatigue, with a focus on the role of lighting design in prevention and mitigation. The paper begins by defining visual fatigue as a multifactorial syndrome characterized by ocular discomfort (e.g., dryness, photophobia) and visual disturbances (e.g., blurred vision), often accompanied by systemic symptoms like headaches. Epidemiological data reveal particularly high prevalence (50-90%) among office workers and students, driven by environmental factors including improper lighting (23% of cases), excessive blue light exposure, and screen flicker. Notably, 71.3% of dry eye patients exhibit concurrent visual fatigue, underscoring the bidirectional relationship between ocular surface health and accommodative strain. A critical analysis of lighting parameters identifies four key aggravating factors: (1) non-adaptive brightness (either<100 lux or >1000 lux), (2) high-color-temperature light (>5000 K) with elevated blue wavelengths (450-490nm), (3) perceptible flicker (<80 Hz), and (4) non-uniform illumination creating >3:1 contrast ratio. These factors disrupt pupillary reflexes, accelerate tear film evaporation (blink rate reduction by 60% in dim light), and induce ciliary muscle spasms.