Wavelength variable optical filter

A wavelength variable optical filter, comprising:

• a first substrate including a first filter region and a first bonding region;
• a second substrate including a second filter region and a second bonding region, and
• a bonding film located between the first bonding region of the first substrate and the second bonding region of the second substrate, wherein
• the first filter region and the second filter region correspond to a wavelength variable filter,
• the first substrate includes a first base body and at least one first reflective film, the at least one first reflective film being located at the first base body within the first filter region and within the first bonding region,
• the second substrate includes a second base body and at least one second reflective film, the at least one second reflective film being located on the second base body within the second filter region and within the second bonding region,
• the bonding film is in contact with the first reflective film and the second reflective film, thereby bonding the first substrate with the second substrate,
• the bonding film has transparency with respect to light in a predetermined wavelength range, and
• an optical path extending through the first reflective film, the bonding film, and the second reflective film has transparency with respect to the light in the predetermined wavelength range, the optical path having no peak of transmittance with respect to a wavelength range measured by the wavelength variable filter.