Application of the concept of effective refractive index to the measurement of thickness distributions of dielectric films.
In the method to be described, the dielectric film is deposited between two silver films so that the threelayer system constitutes a Fabry-Perot interference filter. It is shown how measurements of the variation of the wavelength of peak transmittance over the surface of the filter can be combined with a measurement of the effective refractive index to obtain precise values of the distribution of relative geometrical thickness of the dielectric spacing layer.
Keay
D
D
Royal College of Advanced Technology,Salford 5, England.
Lissberger
P H
PH