Compact Electro-Optic Sensor Module for Intra-Body Communication Using Optical Pickup Technology

Abstract

We developed a compact and low-cost electro-optic (EO) sensor module for intra-body communication using optical pickup technology. An EO crystal of zinc telluride (ZnTe) mainly contributes to use of the cost-effective optical pickup technology. ZnTe has the shortest wavelength for optical transmission, about 570 nm; therefore it can use a low-cost 790-nm wavelength laser diode widely used in compact disc players. The measured modulation depth of the new EO sensor module was about 1.56 times deeper than our old one. The measured value agreed with the calculated value; therefore, there is no performance deterioration by downsizing the sensor module. The sensor module was successfully applied to 10-Mbps half-duplex intra-body communication.