Product Code: JLA_3_3_19

Authors:
William T. Ham
Harold A. Mueller
Division of Biome´dical Engineering, Department of Biostatistics, Virginia Commonwealth University, Richmond, Virginia

Laser radiation employed in fiber optic communications systems is a possible hazard to the eyes of personnel working with or maintaining such equipment. To investigate the potential hazard of infrared laser wavelengths centered around 1550 nm we exposed the corneas of 12 Dutch belted rabbits to a laser diode furnished by Bell Laboratories. Maximum power output through a 4‐meter fiber optic cable was 5.6 mW. Anesthetized and fully dilated rabbits were exposed for time durations of 1, 10 and 100 s to power levels ranging from 4 to 5.6 mW. There was no evidence of damage from 1 and 10 s exposures even at maximum power level. For 100 s exposures, threshold minimal effects were observed at 4.2 mW; levels of damage increased with power increase up to 5.6 mW, where there was partial loss of the corneal epithelial cell layer. Power levels used in these exposures were well above those expected to be encountered in fiber optic communication systems using wavelengths centered around 1550 nm but are useful for predicting levels at which ocular damage can be expected.