Design and fabrication of micromechanical variable fiber-optic attenuator

An electromagnetically actuated MEMS variable fiberoptic attenuator was designed and fabricated. The device consists of an electromagnetic microactuator, a fiber alignment component, a ferronickel shutter, and two single mode fibers. The shutter actuated by the microactuator was interposed in the gap between input and output fiber, which can regulate the optical output. Non-silicon surface micromachining technology, which uses copper layer as the sacrificial layer and the electroplated ferronickel as the structure layer, was used to fabricate the shutter. The magnetic and mechanical behaviour of the device was investigated by using analytical methods and ANSYS FEM, and some its geometric structural parameters were then optimized. The attenuator has less than 3dB-insertion loss at 1550nm, greater than 45dB dynamic range, and better than 40dB return loss.