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:
May. 05, 1992
Filed:
Nov. 03, 1989
Takahiro Nakayama, Hitachi, JP;
Kunihiro Tamahashi, Mito, JP;
Moriaki Fuyama, Hitachi, JP;
Hiroyuki Minemura, Hitachi, JP;
Yoshio Sato, Hitachi, JP;
Nobuyoshi Tsuboi, Ibaraki, JP;
Hiroaki Koyanagi, Katsuta, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An optical modulation method and apparatus uses superconductive oxide material for the optical modulation element. The current, magnetic field, temperature or pressure applied to the superconductive oxide material is varied so as to induce a superconduction-normalconduction transition, and the resulting variation in optical characteristics such as the reflectivity, transmissivity or refractive index of the superconductive oxide material modulate the input light. The method and apparatus are fast in operation and simple in structure. The method and apparatus also detect the variation in the current, magnetic field, temperature or pressure as a change in the reflectivity, transmissivity or refractive index of the superconductive oxide material on the basis of a superconduction-normalconduction transition.