Abstract

Fiber Fabry-Perot tunable filters (FFP-TFs)^1,2 play a critical role as wavelength demultiplexers or noise filters in optical communication networks. Fast wavelength tuning in microseconds or less is necessary for high-speed packet-switched optical communication networks.³ One approach to achieve fast tuning in FFP-TFs is to use high-speed electroclinic liquid crystals (LCs) inside the FFP cavity and modulate the cavity refractive index. Bulk LC Fabry-Perot (FP) filters and the initial LC-FFP-TF have demonstrated fast wavelength tuning, in the order of microseconds, at both visible and infrared wavelengths.^4,5 In this paper, we report a high-speed and high-finesse LC-FFP-TF (using a commercial electroclinic liquid crystal, BDH764E) with a relatively uniform tuning time (including rise, fall, and delay time) of <33 μs over 0.4–12 nm wavelength tuning range at 35°C. For the first time, two-wavelength switching was demonstrated and measured in a LC-FFP-TF, and the fast fall and slow rise response of the LC-FFP-TF was observed.

© 1996 Optical Society of America