Specific Absorption Rate and Temperature Increase in Human Eye Subjected to Electromagnetic Fields at 900 MHz

Abstract

Human eye is one of the most sensitive parts of the entire human body when exposed to electromagnetic fields. These electromagnetic fields interact with the human eye and may lead to cause a variety of ocular effects from high intensity radiation. However, the resulting thermo-physiologic response of the human eye to electromagnetic fields is not well understood. In order to gain insight into the phenomena occurring within the human eye with temperature distribution induced by electromagnetic fields, a detailed knowledge of absorbed power distribution as well as temperature distribution is necessary. This study presents a numerical analysis of specific absorption rate (SAR) and heat transfer in the heterogeneous human eye model exposed to electromagnetic fields. In the heterogeneous human eye model, the effect of power density on specific absorption rate and temperature distribution within the human eye is systematically investigated. In particular, the results calculated from a developed heat transfer model, considered natural convection and porous media theory, are compared with the results obtained from a conventional heat transfer model (based on conduction heat transfer). In all cases, the temperatures obtained from the developed heat transfer model have a lower temperature gradient than that of the conventional heat transfer model. The specific absorption rate and the temperature distribution in various parts of the human eye during exposure to electromagnetic fields at 900 MHz, obtained by numerical solution of electromagnetic wave propagation and heat transfer equation, are also presented. The results show that the developed heat transfer model, which is the more accurate way to determine the temperature increase in the human eye due to electromagnetic energy absorption from electromagnetic field exposure.