Fabrication of Variable Optical Attenuator With Low Insertion Loss

A voltage-controlled variable optical attenuator (VOA) based on silica-based planar lightwave circuits (PLC) was fabricated by flame hydrolysis deposition (FHD). The variable attenuator with Cr heater achieves 20dB attenuation with 3l8mW electrical power at 1550 nm. The insertion loss and the polari