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:
Jun. 16, 1998
Filed:
Dec. 19, 1995
Hitoshi Kawai, Kawasaki, JP;
Jun Kawakami, Yamato, JP;
Akira Ishida, Tsuchiura, JP;
Kouichi Tsukihara, Ota, JP;
Nikon Corporation, , JP;
Abstract
A second harmonic generation (SHG) device is used for conversion of wavelength. The direction of polarization of light beams is suitably rotated by a direction-of-polarization rotating unit, for example by 45.degree., and thereafter these light beams are guided into the SHG device. This can minimize attenuation of intensity of light beam due to conversion of wavelength. Hence, using this direction-of-polarization rotating unit in the apparatus for measuring the medium, the intensity of light being incident upon the photodetector can be increased, whereby the refractive index of the medium can be measured more accurately than by the conventional apparatus.