The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 17, 1991
Filed:
Oct. 13, 1988
Tami Isobe, Yokohama, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A method for measuring refractive index of a thin film layer formed on the other layer having a known refractive index includes following steps. A step of irradiating P-polarized monochromatic light and S-polarized monochromatic light individually on the thin film layer with a prescribed angle of incidence, a step of determining reflections R.sub.p and R.sub.s for the P-polarized monochromatic light and S-polarized monochromatic light, respectively, by detecting luminous intensity of reflected light from the thin film layer, and a step of specifying the refractive index of the thin film layer by prescribed calculation either using the amount of phase changes produced by the reflection of said P-polarized light and S-polarized light on a boundary surface between the thin film layer and the medium, the phase changes being determined in accordance with the refractive index of the medium and the reflectances R.sub.p and Rs, or using the amount of phase changes of lights during propagation from an upper surface of the thin film layer to a lower surface thereof the phase changes being determined in accordance with the refractive index of the medium and the reflectances R.sub.p and R.sub.s.