A liquid crystal variable optical attenuator designed for power management in optical networks has been announced by Lightwaves2020 Inc. This voltage-controlled attenuator has a dynamic range of 20 dB and operates in the S-, C- and L-bands. It is sealed in a 5.5-mm-diameter coaxial package, suitable for integration onto circuit boards. The company says that the device offers low insertion loss and low power consumption, and that it is more reliable than mechanical attenuators because it has no moving parts. Applications include pre-emphasis of DWDM laser signals in long-haul systems, power equalization in optical add/drop modules and cross connects, and gain-tilt adjustment in erbium-doped fiber amplifiers.