P 2Potential risks of blue light retinal damage induced by high energy white LEDs
K. A. Breidenbach, R. Schwartz, W. Wöllmer
Purpose: Especially for small area illumination e. g. for reading lights LEDs with highly luminous white emission have been developed. The potential risks of blue light retinal damage induced by high energy white LEDs was investigated.
Methods: We used LED-lamps which are based on InGaN-material technology. A blue light LED die is coated by yag-phosphor to produce white emission coulour. The diameter of the LED was 3 or 5 mm, the viewing angle is determined in the range between 15° and 20° and an actual intensity of 2 to 4 cd. The potential risks mainly depends on pupillary diameter, light intensity and distance to LED, exposure time and rate of different wavelengths.
Results: In our study we prove in different scenarios the potential risks for blue light hazards using the guidelines and limits of exposure to broad band incoherent optical radiation by the "International Commission on Non-Ionizing Radiation Protection".
Conclusion: Following the worst case it is imaginable that retinal damage induced by new high energy white LEDs may occur and for safty reasons warning hints should be mandatory in special cases.
University of Hamburg, Department of Ophthalmology, Martinistr. 52, D - 20246 Hamburg