A Preliminary study on Numerical Dosimetry for Ocular Exposure at 60GHz

INTRODUCTION Technologies with millimeter-waves (MMWs) have been popularized in our daily life. It warrants to investigate biological effect to concern MMW exposure. In the recent research, ocular injuries caused by MMW exposure were discussed[1]. In that in-vivo study, rabbit eyes were exposed to MMW at 60GHz to observe clinical courses of ocular damages. It is not clear the causal connection between ocular damages and exposure levels. The simulation study in three-dimensional (3D) thermal transportation cooperating with 3D electromagnetic analysis is useful to understand the mechanism of heat transportation due to the MMW exposure. However, there is not sufficient information on the numerical electromagnetic analysis in the MMW band with finite-difference time domain (FDTD) method[2]. We are now preparing for electromagnetic dosimetry for the rabbit eye at 60 GHz MMW exposure with the FDTD method[2]. Before performing the dosimetry, preliminary numerical simulation is required, because behavior of the FDTD method is not clear when electric conductivities of biological tissue become large. A purpose of this study is to clarify the behavior of numerical solution obtained with the FDTD method in the MMW. A dielectric sphere is employed as rabbit ocular model for the preliminary analysis.
 The numerical solution is compared with that obtained from Mie theory[3].