EFFECT OF ILLUMINANCE ON BLINK RATE DURING TABLET USE: A PILOT STUDY

Abstract

This study investigated the effect of illuminance on blink rate and eye strain during tablet use, comparing 150 lux and 500 lux environments. Thirty participants aged 18-35 years with normal ocular health read text on a 10.9-inch iPad Air for 30 minutes at 40 cm viewing distance under controlled Daylight (6500 K) illuminance in an experimental research design. Outcome measures included blink rate, incomplete blink rate, and eye strain assessed by the ASQ-17 questionnaire, analyzed using Paired t-test and Wilcoxon Signed-Rank Test (α = 0.05). The 500 lux condition produced a significantly higher mean blink rate (7.84 ± 0.30 blinks/min; 95% CI: 7.72, 7.95) compared to 150 lux (7.74 ± 0.30 blinks/min; 95% CI: 7.63, 7.85) (p < 0.001). Incomplete blink rate was also significantly higher under 500 lux (1.62 ± 0.28 blinks/min; 95% CI: 1.51, 1.72) than 150 lux (1.56 ± 0.27 blinks/min; 95% CI: 1.46, 1.66) (p < 0.001). Eye strain prevalence was 70.00% under 150 lux and 63.33% under 500 lux, with no statistically significant difference (p = 0.69). These findings indicate that illuminance affects blink behavior, potentially through ocular response and adaptation mechanisms. Results may inform evidence-based design of tablet-use environments and support future research on dry eye and eye strain prevention.

Keywords: Illuminance, Blink Rate, Incomplete Blink, Tablet, Dry Eye, Eye Strain