MEMS Optical Attenuators for DWDM

Abstract

We developed an array of shutter-type multi-channel variable optical attenuators (VOA) for Dense Wavelength Division Multiplexing (DWDM) based on high-aspect-ratio electrostatic comb drive actuator fabricated by silicon bulk micromachining. Applying a voltage between the driving comb fingers and the fixed comb fingers results in the displacement of the driving comb fingers by an attractive electrostatic force The VOA achieves large attenuation dynamic range of up to 55 dB with drive voltage of 65 V and shows the insertion loss of less than 0.1 dB, the return loss of 51.6 dB for a 3-dB attenuation and the Polarization Dependent Loss (PDL) of 0.2 dB for a 3-dB attenuation.