Thin-film interference filters are constructed with a generalized pattern of layers differing in both thickness and refractive index to produce spectral responses appropriate for adjusting optical power among a plurality of different wavelength channels. Each of the layers is composed of unit sub-layers...http://www.google.es/patents/US6611378?utm_source=gb-gplus-sharePatente US6611378 - Thin-film interference filter with quarter-wavelength unit sub-layers arranged in a generalized pattern
Thin-film interference filter with quarter-wavelength unit sub-layers ...
