Nonlinear optical effects and trends of near-infrared laser retinal damage

Recent changes in the maximum permissible exposure limits (MPE) for near-infrared (NIR) laser exposures are analysed in light of nonlinear optical phenomena. We have evaluated the thresholds for supercontinuum generation for ultrashort laser exposures in the NIR and compared these with the MPE’s. Because of the strong increase in ocular absorption in the 1.2 to 1.4 micrometer range, evaluation of this phenomenon is necessary because any shift in laser energy in the eye to shorter wavelengths could lead to unforeseen increases in hazards for the retina. Trends will be discussed regarding proposed changes to the safe exposure limits in the NIR regime.