Accession Number : AD0438012

Title :   A METHOD FOR DETERMINATION OF THE OPTICAL CONSTANTS OF THIN ABSORBING LAYERS,

Corporate Author : HEBREW UNIV JERUSALEM (ISRAEL)

Personal Author(s) : Harris,J. ; Weinberger,H.

Report Date : AUG 1963

Pagination or Media Count : 16

Abstract : A method has been developed by which the optical constants of an absorbing layer on an absorbing base can be determined. The amplitude and phase of the light reflected by such a ststem is a known function of the parameters - complex refractive indices of film and substrate, film thickness and gngle of incidence. But the equations are intractible and cannot be solved for refractive index of the film. The use of a search technique for an electronic computer makes the reverse calculation possible. Given suitable starting values, one can determine rather quickly the film index giving rise to measured values of the intensity and phase difference of the reflected light. Application of this method to thin layers of nickel black shows that the layer is inhomogeneous. The consequences of inhomogeneity are discussed. Many of the values for the optical constants of thin films which have been reported by other workers are, in fact, average values for inhomogeneous layers. Such values have only limited significance in predicting the optical behaviour of inhomogeneous layers. (Author)

Descriptors :   (*METAL FILMS, OPTICAL PROPERTIES), ABSORPTION, LIGHT, PHASE MEASUREMENT, EQUATIONS, REFRACTIVE INDEX, DIGITAL COMPUTERS, ANALOG COMPUTERS, INTENSITY, REFLECTION, NICKEL, MATERIALS, POLARIZATION, INTERFERENCE, OPTICAL FILTERS

Distribution Statement : APPROVED FOR PUBLIC RELEASE