Dispersion implementation in optical filter design by the Fourier transform method using correction factors.
The Fourier transform method to design graded-index optical filters, that relates the desired reflection spectrum and the index profile through the use of a Q function, has two important drawbacks: (1) It relies on approximate Q functions, and (2) it does not account for the dispersion of the index of refraction. The former is usually addressed by an iterative correction process. We propose to address the latter by scaling the wavelength in the Fourier transform by the optical thickness of the filter and to multiply the Q function by a wavelength-dependent correction factor. We demonstrate the high effectiveness of this approach by the performance of optical filters designed with such correction factors using the optical properties of SiO2/TiO2 mixtures.
Larouche
Stéphane
S
Regroupement québécois sur les matériaux de pointe and Department of Engineering Physics, Ecole polytechnique de Montréal, Québec, Canada. stephane.larouche@polymtl.ca
Martinu
Ludvik
L
D004867:Equipment Design; D005583:Fourier Analysis; D015233:Models, Statistical; D055095:Optics and Photonics; D012822:Silicon Dioxide / Q000737:chemistry; D013059:Spectrum Analysis, Raman; D014025:Titanium / Q000737:chemistry
C009495:titanium dioxide; D012822:Silicon Dioxide; D014025:Titanium