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. 09, 1992
Filed:
Jan. 24, 1991
Keisuke Shinozaki, Tokyo, JP;
Toshio Nonaka, Tokyo, JP;
Oki Electric Industry Co., Ltd., Tokyo, JP;
Abstract
An element for generating second-harmonic waves of a short wavelength from a fundamental wave emitting from a semiconductor laser and the like. The element includes a substrate made of a ferroelectric crystal, a second-harmonic wave generator for generating a second-harmonic wave from a fundamental wave entered therein, and periodically arranged portions formed in a front stage region and a rear stage region of the element. The periodic portions or structures, each have pairs of parts or regions of a high optical refractive index and of a low optical refractive index so as to confine the fundamental waves in the second-harmonic wave generating portion. These regions have various kinds of material diffused or introduced therein and of a thickness. According to another example of the element, the sign of a nonlinear optical coefficient of the region is periodically reversed and the region satisfies a quasi-phase-matching condition.