Patent ID: 7113689

Claim:
A micro-electro-mechanical system (MEMS) variable optical attenuator, comprising: a substrate having a planar surface; a micro-electric actuator arranged on the planar surface of the substrate; a first optical waveguide having a receiving end and a second optical waveguide having a transmitting end, said optical waveguides being coaxially arranged on the planar surface; an optical shutter driven by the micro-electro actuator and movable to a predetermined position between the receiving end and the transmitting end of the optical waveguides; and a surface layer formed on the optical shutter; wherein said surface layer has a reflectivity less than 80% so as to allow transmission of a portion of incident light into said surface layer; said surface layer further has a light extinction ratio and a thickness for extinguishing the transmitted portion of said incident light in said surface layer; and the surface layer is formed of a material selected from the group consisting of Ti, TiO 2 , Cr, CrO 2 , W, Te and Be.