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:
Apr. 21, 1981
Filed:
Apr. 18, 1979
John W Berthold, III, College Park, MD (US);
Abstract
A variable integrated optical logic element, formed on a substrate of electro-optic material, capable of being controlled to perform the six basic logic operations AND, OR, EXCLUSIVE OR, NAND, NOR and EXCLUSIVE NOR. The optical logic element comprises a plurality of single-mode optical waveguides which form a group of parallel and series equal-arm interferometers. The optical logic element operates on the principle of constructive and destructive interference between light beams. Voltage means are provided for varying the index of refraction of certain of the optical waveguides, to produce relative phase differences in the light energy propagating therein. By inducing phase shifts in the light energy propagating in appropriate waveguides, each of the six basic logic operations can be performed. Also disclosed is an electrically passive, phase-sensitive optical coupler, which is used for switching light energy between waveguides. The switching operation performed by the phase-sensitive coupler is a function of the presence or absence of and the relative phase differences between the light energy input to the coupler.