A high sensitivity humidity sensor based on micro-ring resonator with three coupling points

摘要

A novel high sensitivity humidity sensor based on micro-ring resonator with three coupling points (MRRTCP) is reported. Since the dielectric constant of Polyimide is highly sensible to the relative humidity of the environment, we choose the Polyimide (PI) as the moisture material. The effective refractive index of the sensing part of the sensor changes as the relative humidity of the environment changes, this leading to an obvious shift of the output spectrum. The sensing range of the relative humidity sensor is 0～100%RH, and the sensitivity is 0.0017μm/%RH, and the structure is relatively simple and could be used in micro-scale humidity sensing.