uv bandpassfilter and application in uv detector or light - emitting device

摘要

A UV-bandpass filter for transmitting therethrough light having a wavelength included in a UV-region. The bandpass filter is an optical filter including a thin silver film; wherein the thin silver film includes an entrance face and an exit face opposing the entrance face, for emitting light having a wavelength included in a specific UV-region whose wavelength ranges from 250 nm to 400 nm in the light having reached the entrance face, and has such a thickness as to yield a transmittance of 10% or less with respect to light having a wavelength excluding the specific UV-region.