Wavelength variable interference filter, optical module, and light analyzer

A wavelength variable interference filter, comprising:

• a first substrate;
• a second substrate disposed so as to be opposed to the first substrate;
• a first reflection film provided on a surface of the first substrate that faces the second substrate;
• a second reflection film provided on a surface of the second substrate that faces the first substrate, the second reflection film being disposed so as to be opposed to the first reflection film with a predetermined gap interposed therebetween;
• and
• a gap varying unit which changes the length of the gap between the first reflection film and the second reflection film, the gap varying unit including a first electrode formed on the surface first substrate and a second electrode formed on the surface of second substrate,
• wherein
• the first substrate has a first movable portion on which the first reflection film is disposed, and a first linkage portion which holds the first movable portion in such a manner that the first movable portion can shift in the thickness direction of the first substrate,
• the second substrate has a second movable portion on which the second reflection film is disposed, and a second linkage portion which holds the second movable portion in such a manner that the second movable portion can shift in the thickness direction of the second substrate,
• the gap varying unit varies the length of the gap by shifting the first movable portion and the second movable portion relative to each other by changing an interaction force between the first movable portion and the second movable portion,
• a thickness of the first movable portion is greater than a thickness of the first linkage portion, and a thickness of the second movable portion is greater than a thickness of the second linkage portion,
• the first and second linkage portions have the same thickness, and
• a shape of the first linkage portion matches a shape of the second linkage portion in a plan view from the thickness direction of the first substrate and the second substrate.