Patent ID: 11960074
Assignee: SEIKO EPSON CORPORATION
Field: nan (nan)
Classification: CPC nan | IPC G

Claim 5:
6. An optical filter comprising:
a pair of reflection films facing each other via a gap; and
an actuator that changes a distance between the pair of reflection films, wherein
each of the reflection films are formed by a multilayer film in which a low-refractive layer is sandwiched by a pair of high-refractive layers, and
in each of the multilayer films of each reflective film, optical film thicknesses of the high-refractive layers and optical film thicknesses of the low-refractive layers are film thicknesses are based on a design center wavelength that is set with respect to that particular multilayer film, and
the design center wavelength in each of the multilayer films of a respective reflective film are different, and the design center wavelengths are smaller toward the gap, and
a difference between the design center wavelengths of the adjacent layers takes a constant value.