Design of a New-Type Electro-Optical Sensor Based on the Total-Internal Reflection Theory in Heterodyne Interferometry

Abstract

In this paper, a new-type electro-optical sensor based on the total-internal reflections theory in heterodyne interferometry is proposed. The sensor is designed as a semi-circle shape. It is made of BK7 glass with the refractive index of 1.51509. And the end surface of the sensor is designed as a micro-mirror. The phase difference between s-and p-polarizations at the output of the optical fiber sensor can be obtained when a heterodyne optical source is launched into the electro-optical sensor at a suitable incident angle. By numerical calculation, the resolution of the system by using the intensity method can reach refractive index unit (RIU) in the measurement range of. The electro-optical sensor could be valuable for chemical, biological and biochemical sensing. It is with some advantages, such as, high resolution and stability, high sensitivity and real-time measurement.