Variable optical attenuator

Abstract

A variable optical attenuator (10) includes a cover (2) and a housing (3) defining an interior space therebetween for accommodating an optical module (4) and a reciprocating device (5). The reciprocating device includes a carrier (53) mounted to and driven by a screw rod (55) between opposite extreme positions. A filter (6) having a varying optical density gradient is attached to the carrier (53) to be movable therewith. The optical module includes input and output optical fibers (45, 46). Light signal goes from the input fiber transmits through the filter and reflected by a reflector (42) back to the output fiber (46). By moving the filter with respect to an optical path between the reflector and the input and output fibers, the light signal is attenuated to different extent due to the varying density of the filter. The carrier forms stoppers (511, 512) on opposite sides thereof for abuttingly engaging sidewalls of the housing for preventing over-movement of the carrier with respect to the housing.

Dependencies are inferred from the claim text.