Design and plasma deposition of dispersion-corrected multiband rugate filters

Department of Engineering Physics, Ecole Polytechnique de Montréal, Québec, Canada.
Applied Optics (Impact Factor: 1.69). 10/2002; 41(25):5249-55. DOI: 10.1364/AO.41.005249
Source: PubMed

ABSTRACT Inverse Fourier transform method has been commonly used for designing complex inhomogeneous optical coatings. Since it assumes dispersion-free optical constants, introducing real optical materials induces shifts in the position of reflectance bands in multiband inhomogeneous minus (rugate) filters. We propose a simple method for considering optical dispersion in the synthesis of multiband rugate filter designs. Model filters designed with this method were fabricated on glass and polycarbonate substrates by plasma-enhanced chemical vapor deposition of silicon oxynitrides and SiO2/TiO2 mixtures with precisely controlled composition gradients.

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