Dazzling Glare: Protection Criteria Versus Visual Performance

Laser eye protection was first introduced into the U.S. Fleet when the need arose to protect aviators and aircrew from our own neodymium systems. This protection was designed to reduce the incidence energy below the maximum permissible exposure level established by the American National Standards Institute. Since range finders used an infrared wavelength, as defined and therefore not visible to the eye, there was no possibility of glare. With time more systems were developed employing lasers in both the visible and infrared portion of the spectrum. When the lasing of the police helicopter in Los Angeles was first reported in 1981 it immediately became apparent that for wavelengths in the visible portion of the spectrum substantial losses in visual performance could be encountered at safe exposure levels. The incident emphasized the need to develop laser eye protection based on criteria that encompassed both transient glare and permanent burns, hemorraghic lesions effects. The goal of this research project has been to establish protection levels based on performance rather than damage criteria. Keywords Dazzling glare Visual performance Contrast sensitivity Perimetry.