Simulation of Micro-Displacement Sensor Using Photonic Crystals

In this paper, we designed a micro-displacement sensor using of two-dimensional photonic crystal structures. This structuer is a hexagonal that on each side located seven holes osilicon. The holes made of air that have been arranged in silicon background. The holes have been arranged in a triangular arrangement. In this micro sensor, first by using the finite difference time domain simulation method, optimal values for frequency and lattice constant of photonic crystal were calculated. The intensity of propagating waves was obtained in two micrometers of left side of the structure. In the meantime, the output intensity is as a linear function of the displacement. the sensitivity was obtained as . The values of this structure showed that at a proper operating wavelength, the structure could be used as the micro - displacement sensor that also has very good sensitivity.The micro - displacement sensor is an important measurement system in many applications such as the micro – electro - mechanical systems, aerospace, structure health monitoring, and many engineering fields.