Novel optical torsion-mirror components for fiber sensing or networking applications

A new kind of optical torsion-mirror components with advanced compound driving structures as well as novel folding torsion-spring structures are fabricated in SOI wafers by using the mixed micromachining based on the surface and bulk silicon microelectronics. The electromechanical performances of the components and the optical properties of their micromirrors are investigated experimentally and theoretically. The theoretical and experimental studies manifest that the compound driving structures and folding torsion-spring structures are much benefit to decreasing the yielding voltages of actuating the mirrors and, thus, making their tilting motion easier. The micromirrors of the components can cyclically vibrate a few 106 times at least between 0° and 90°, and their shortest actuating time can reach an estimated less than 2.5 ms. The surface roughness and its distribution of the micromirrors of the components are small and smooth, respectively, which is acceptable for wavelength division multiplexing applications basically. The theoretical model of the coupling loss between input and output fiber ends is obtained when the torsion-mirror components are brought into use as optical switches or attenuators, etc. in fiber sensing or networking systems.