An interferometer includes: a first glass plate optically coupled to a second glass plate, forming an optical interferometric cavity therebetween; a first reflective coating coupled to the first glass plate within the optical interferometric cavity, where the first reflective coating is partially reflective; a second reflective coating coupled to the second glass plate within the optical interferometric cavity, where the second reflective coating is at least partially reflective; and a tuning plate residing within the interferometric cavity and optically coupled to the first and second reflective coatings, where the tuning plate comprises a photosensitive material, where a refractive index of the photosensitive material may be modified by exposure to light. The interferometer is adjusted through exposure of the tuning plate to light so that its pass, transmission, or reflection bands align to standard channel positions, or the pass bands of an apparatus incorporating the interferometer align to standard channel positions.