Wireless personal communication is a rapidly expanding sector, particularly
in the field of cellular mobile phones and wireless local area networks
(WLANs). In an indoor WLAN system, the user of the mobile terminal can
find himself in close proximity to the radiating antenna. It is therefore
important to consider possible health hazards due to this type of exposure.
As the most considered adverse effects of the EM fields are of thermal
nature, particularly with reference to the eye, in this work we have evaluated
the temperature increase induced in a human eye exposed to WLAN-like fields.
In particular, we have considered possible WLANs operating in the range
between 6 and 30 GHz, so that the incident field can be simulated via a
plane wave. As a first step we have computed the specific absorption rate
(SAR) distribution in a human eye anatomical model, developed from the
"Visible Human" data set, by using the Finite Difference Time Domain (FDTD)
numerical technique with a cell resolution of 0.5 mm. Starting from the
calculated SAR values, the heating distribution has been derived through
the bio-heat equation, which has been solved using an explicit finite difference
scheme. Temperature increases in the order of 0.04 °C have been calculated
in the eye lens with an incident power density of 1 mW/cm2 at 6 GHz. Lower
heating is obtained in the lens when the frequency increases. Considerations
about the exposure limits in the considered frequency range are finally
made