Effect of metal-framed spectacles on microwave radiation hazards to the eye of humans.
A novel measurement technique using a monopole antenna probe has been applied to a full-size, image-plane type model of a human to determine the microwave fields near the eyes and to evaluate the effect of scattering structures, such as metal-framed spectacles, on those fields. The measurement technique relies on a 'subtraction' technique to determine the changes in fields when a scattering structure is introduced, and allows a large number of measurements to be performed in a relatively short space of time and with a high degree of accuracy. Investigations conducted in an anechoic chamber yield angles of incidence, test frequencies and wave polarisation values that give details of shielding, enhancement and depolarisation effects due to this particular scattering structure that appeared not to have been previously studied. It has been found that the introduction of a pair of metal-framed spectacles can, in certain cases, cause an increase in field levels by up to approximately 20 dB, a significant perturbation of the incident microwave field which should be accounted for in the setting of safety standards relating to acceptable levels of incident power.
Davias
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N
Griffin
D W
DW
D005123:Eye / Q000528:radiation effects*; D005139:Eyeglasses; D006801:Humans; D008670:Metals / Q000009:adverse effects*; D008872:Microwaves / Q000009:adverse effects*
D008670:Metals