Polarization independent two-way variable optical attenuator based on polymer-stabilized cholesteric liquid crystal.

We have investigated the optical properties of the polymer-stabilized cholesteric liquid crystal (CLC). It was observed that the reflectance was decreased and the transmittance was increased with the increase of the applied voltage. Based on this property, a polarization independent two-way variable optical attenuator (VOA) has been demonstrated by sandwiching a lambda/2 film between two left handed polymer-stabilized CLC films. Different from a conventional VOA, the VOA based on our developed polymer-stabilized CLC can continuously change the optical intensity in both the reflection and transmission directions by applying voltage on it. This unique property will allow it to be widely used in many applications, such as optical communications. (c) 2010 Optical Society of America.