“…This geometrical inverse problem is quite well studied in the literature see [4] and several methods have been proposed to solve it. In this paper, we focus on one of these method, called the enclosure method, which is initiated by Ikehata, see for examples [2,3], and developed by many researchers [7,9,14,18,19,20], [6,19] for the acoustic model, [5,9] for the Lamé model and [7,21] for the Maxwell model. The testing functions used in [7,21] are complex geometric optics (CGO) solutions of the isotropic Maxwell's equation.…”