Optical tunable filter and method of manufacturing the same

摘要

An optical tunable filter has a fixed substrate having a first recess formed therein and a movable substrate bonded to the fixed substrate. The movable substrate includes a movable portion having an opening formed at a location facing the first recess and a support portion for supporting the movable portion so that the movable portion can be displaced. The optical tunable filter also has a light-transmittable substrate bonded to the movable portion, a fixed reflection film formed on a bottom of the first recess, and a movable reflection film formed on a surface of the light-transmittable substrate. The optical tunable filter includes an interference gap formed between the fixed reflection film and the movable reflection film. The optical tunable filter also includes an actuator operable to displace the movable portion relative to the fixed substrate.