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:
Jan. 20, 1998
Filed:
Dec. 20, 1995
Kazuhito Tajima, Tokyo, JP;
NEC Corporation, , JP;
Abstract
The invention provides an all-optical switch including (a) polarizing beam splitters for introducing propagation time difference A to vertically and horizontally polarized components of a signal light, (b) a semiconductor waveguide for impressing phase modulation to the signal light; (c) a polarizing beam splitter and mirrors for introducing propagation time difference B, which is opposite to said propagation time difference A, to the vertically and horizontally polarized components of the signal light, (d) a half-wave plate for making polarization of the vertically and horizontally polarized components to coincide with each other, and (e) a half mirror for making the vertically and horizontally polarized components to interfere with each other. The all-optical switch in accordance with the invention has advantages that switch-off time is not limited by the slow longitudinal relaxation time of non-linear effects, and that it has long term stability because it includes only one non-linear portion.