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:
Oct. 30, 2001
Filed:
Sep. 15, 2000
Gary E. Betts, Westford, MA (US);
Massachusetts Institute of Technology, Cambridge, MA (US);
Abstract
This is an electro-optic modulator having an electro-optic substrate such as lithium niobate, an optical waveguide defined within the substrate, an electrode structure including a microwave transmission line elevated from the substrate by conductive legs. In one embodiment, a low-dielectric constant buffer layer is disposed between the substrate and the transmission line. The conductive legs extend from the transmission line to a surface of the substrate toward the waveguide, through the buffer layer. The microwave transmission line is elevated from the substrate at a distance such that the electrical propagation velocity is at a maximum. The high electrical velocity is offset by a loading capacitance introduced by the conductive legs which slows the electrical velocity down on the transmission line to match the optical velocity. Pairs of opposing conductive legs provide a strong electric field for modulating the optical signal.