A Study of Full-Spectrum Screen Lighting for Reducing Screen-Related Eye Fatigue and Dry Eye

This study will evaluate whether full-spectrum screen bar lighting can reduce eye fatigue and dry eye symptoms after a standardized screen task. Prolonged screen use is common in daily work and study and may cause blurred vision, eye soreness, dryness, headache, and reduced attention. Light environment may be one way to improve visual comfort during screen use, but more controlled clinical evidence is needed. In this randomized, parallel-group controlled study, 112 healthy adult participants will be assigned to either a full-spectrum screen bar lighting group or a brightness-matched control group without screen bar lighting. Participants in both groups will complete an approximately 2-hour standardized screen task in a controlled laboratory environment. The study will compare changes before and after the task in objective and subjective measures of visual fatigue and dry eye, including critical flicker fusion frequency, visual fatigue questionnaire scores, eye movement and blinking parameters, pupil parameters, tear film-related measurements, and dry eye symptom scores. Safety and discomfort during the study will also be recorded.

Inclusion Criteria: 1. Age 18 to 35 years, male or female. 2. Average daily electronic screen exposure of at least 4 hours. 3. Near visual acuity at 40 cm of 0.5 or better, and able to complete the study 1. tasks and measurements stably. 4. Able and willing to provide written informed consent. Exclusion Criteria: 1. Presence of ocular inflammation or ocular disease. 2. History of severe systemic disease, neurological disease, or psychiatric disorder. 3. Pregnancy or lactation. 4. Use of dry eye or visual fatigue treatments, or contact lens wear, within 1 month before the study. 5. History of ocular surgery within the past 6 months. 6. Daily use of lenses with blue-light blocking, photochromic, polarized, filtering, or similar optical functions. 7. Professional background in ophthalmology or optical products. 8. Intake of caffeine or other stimulants within 4 hours before the study. 9. Best-corrected visual acuity (BCVA) less than 0.8. 10. Anisometropia of 1.00 diopter or greater, or astigmatism of ±2.00 diopters or greater. 11. Intraocular pressure (IOP) less than 5 mmHg or greater than 21 mmHg. 12. Non-invasive tear breakup time (NIBUT) less than 5 seconds in either eye. 13. Ocular Surface Disease Index (OSDI) score of 33 or greater.