Determination method of optical properties

A new parameter called the coefficient of reflectivity differentiated with respect to the wavelength of light (dR/dλ) is introduced. This parameter is used to describe a new method of determining the optical properties, a refractive index, and the thickness of nonabsorbent thin films from reflectivity R and a differential coefficient (dR/dλ) for either s-polarized light or p-polarized light. It is also shown that optical properties can be obtained from reflectivity R and a coefficient of reflectivity differentiated with respect to the incident angle of light (dR/dθ).