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Pupil Size in Outdoor Environments.
Stephanie K Harley1, David H Sliney2
1U.S. Air Force, 1160 Air Force Pentagon, Washington, DC 20330.
Health Physics
|July 26, 2018
Summary
Pupil size is crucial for assessing laser-induced retinal injury risk in daylight. This study measured pupil diameter in 87 subjects under bright light conditions, providing essential data for safety assessments.
Area of Science:
- Ophthalmology
- Optometry
- Biomedical Engineering
Background:
- Pupil size significantly influences retinal illumination, impacting the risk of laser-induced retinal injury.
- A century-long gap exists in laboratory pupillometry data, particularly under daylight conditions.
Purpose of the Study:
- To measure and document pupil diameter under realistic daylight conditions.
- To address the data gap in pupillometry relevant to laser safety.
Main Methods:
- Photographic technique with a fixed chin/headrest and digital camera platform.
- Digital image analysis using computer software to determine pupil diameter.
- Measurements conducted on 87 subjects viewing a full-field neutral screen.
Main Results:
- Average pupil size was 2.39 mm at an average screen luminance of 1,473 cd/m².
- Measured pupil diameters ranged from 1.44 mm to 3.03 mm.
- Data stratified by luminance, sex, eye color, and age.
Conclusions:
- Provides essential, contemporary data on pupil size under daylight conditions.
- Contributes to a better understanding of retinal illumination for laser safety protocols.
- Highlights the variability of pupil size across different individuals and conditions.
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