Optimum sensitivities of D-type optical fiber sensor at a specific incident angle

Abstract

The optimum incident angle for a 4 mm long and 4 μm core thickness D-type optical fiber sensor in the intensity measurements is near at 89°. The sensitivity is higher than 40 (1/RIU) and its resolution is better than 2.5×10-5 RIU. This sensor is used to detect the refractive index or gas or liquid concentration in real-time, and it has some merits such as small, simple and inexpensive and provides an in vivo test.