UV-bandpass filter and application to UV-detecting apparatus or light-emitting apparatus
AssigneeHamamatsu Photonics K.K.
InventorsMasayuki Sakakibara, Masaru Morishita
Life of this patent
Estimating the term…
Abstract
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.
Claims5
A UV-bandpass filter for selectively transmitting light having a wavelength included in a specific UV region of 200 nm to 400 nm, comprising:
- a UV-transmitting member that is transparent to at least the light included in said specific UV region;
- and
- a thin silver film having an entrance face and an exit face that opposes said entrance face and that is in direct contact with one surface of said UV-transmitting member, said thin silver film having such a total thickness of at least 80 nm but not greater than 250 nm, as to make the ratio of power of light transmitted from said exit face to power of light incident upon said entrance face be not greater than 10% at any wavelength in a wavelength region of 400 nm to 3000 nm.
Dependencies are inferred from the claim text.