Evaluation of ocular protection filters in field situations

A computer program has been developed to simulate eye movement during pursuit tracking to test the effectiveness of filters protecting the eyesight of individuals exposed to laser radiation. Two types of retinal damage are considered: macular lesions and retinal injury causing vitreous or subretinal hemorrhage. The retinal damage caused by optical radiation in the visible and near infrared of the spectrum differs from almost all other types of hazards in their proabilistic nature. That is, a small movement of the laser beam or change of eye position decreases or increases the probability of injury by several orders of magnitude. A laser beam combines the problem of a small source with extreme directionality with the probabilistic nature of this hazard location in space, and we now add the probabilistic nature of the action of the protective filter, i.e., a dependence upon angle of incidence. From this combination, an even more probabilistic picture of injury or disablement emerges. When it is necessary to plan the probabilities during military operations of mission fulfillment or injury with regard to various types of lasers in the battlefield ++environment, the problem must be analyzed very carefully. Our solution of the problem indicates the type of injuries to be expected and their dependence upon the various parameters of the angle of incidence of the lasers on the protective filters in the viewing system.