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:
Sep. 04, 1979
Filed:
May. 13, 1977
Frederick J Leonberger, Carlisle, MA (US);
Joseph P Donnelly, Carlisle, MA (US);
Massachusetts Institute of Technology, Cambridge, MA (US);
Abstract
A planar semiconductor optical waveguide, modulator, variable coupler and switch are described. The waveguide has an epitaxial layer on a semiconductor substrate. Two spaced strips of opposite conductivity type are implanted in the layer to form an optical waveguide channel in the space. By closely spacing two waveguide channels so that they have a common strip and a strip outside each channel, coupling is obtained between the channels. For a switch, the coupling length is such that substantially all the optical energy in the input channel is coupled to and emerges from the other channel. Reverse biasing one of the outside strips causes the optical energy to divide between the input channel and the output channel to provide output power modulation or variable coupling, and substantially complete transfer of power (switching) for a particular value of reverse bias.