Edge interference filter for optical communication transmission in wavelength-division multiplex

摘要

An edge interference filter is composed of a layer sequence of a total of 21 alternately arranged high refractive index layers and low refractive index layers with the high refractive index layers being composed of TiO2 and the low refractive index layers being composed of SiO2. The individual layers having an optical layer thickness standardized to a 20 DEG angle of incidence and to 3/4 wavelength of the attenuation band center wavelength of 823 nm with the first and twentyfirst layers having a thickness of 0.241 of the standardized thickness, the second and twentieth layers having a thickness of 0.914 of the standardized thickness and the remaining third through nineteenth layers having a thickness of one standardized thickness.