In Sossi’s formulation of the Fourier transform method of optical multilayer design the refractive-index profile is derived for an inhomogeneous layer of infinite extent having the desired spectral transmittance. This layer is then approximated by a finite system of discrete homogeneous layers. Because it does not make any assumptions about the refractive indices, thicknesses, or number of layers, it is the most powerful analytical method proposed so far. The method has been programmed for a computer and combined with other numerical design procedures. With the program it is possible to design filters with almost any desired transmittance characteristics using realistic refractive indices.
© 1978 Optical Society of America
J. A. Dobrowolski and D. Lowe, "Optical thin film synthesis program based on the use of Fourier transforms," Appl. Opt. 17, 3039-3050 (1978)