TUNABLE INTERFERENCE FILTER, OPTICAL MODULE, PHOTOMETRIC ANALYZER, AND MANUFACTURING METHOD OF TUNABLE INTERFERENCE FILTER

摘要

A tunable interference filter comprising a first substrate, a second substrate facing the first substrate, a first reflection film formed on the first substrate, a second reflection film formed on the second substrate, the second reflection film facing the first reflection film by interposing a gap, and a gap adjustable-part that adjusts the gap, wherein the second substrate has a first surface and a second surface opposed to the first surface, wherein the second substrate includes a first groove on the first surface, and wherein the second substrate includes a second groove on the second surface, the second groove facing the first groove.