Rayonnement laser: Risques oculaires et normes de protection

Abstract

The risk for biological tissues to be damaged by a laser beam is mainly determined by their optical properties. Laser radiations emitted in ultraviolet and infrared B and C represent a hazard for the anterior segment of the eye. Depending the wavelength, laser radiation is absorbed by the cornea, the lens or both. The lower damage thresholds are reported at the retinal level, in the spectral range of 400 to 1 400 nm. The exposure limit values, recommended by laser safety standards, are evaluated with wavelength, exposure duration, pulse repetition frequency and the size of the visual angle subtending the source. The fast evolution of laser products induces a continuous revision of guidelines. Next revision of European standard EN 60825-1/A2 will include subnanosecond limit values, changes in the continuous wave exposure limits and a new classification of laser products susceptible to be in agreement with next ANSI and FDA/CDRH laser safety standards. © EDP Sciences.