The Action of Microwave Radiation on the Eye^†

Abstract

Microwave power can cause formation of opacities in the lens of the rabbit eye exposed to continuous wave or pulsed wave radiation at frequencies from 2.45 GHz to 10 GHz. When the eye is irradiated in a free field, the opacity (cataract) develops in the posterior part of the lens; in location, form and growth, it resembles cataracts caused by ionizing radiation. When the eye is irradiated at the same frequencies as part of a ‗closed‘ waveguide system, the cataract develops in the anterior part of the lens, like those caused by infrared radiation. Although for every power level there is a minimal exposure period which will cause an opacity, repeated shorter exposures can have a cumulative effect, the main determining factor being the time interval between successive exposures. Experimental evidence suggests that micro-wave cataracts are not simply a result of microwave heating but are caused by some other property of the radiation.