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. 27, 2009
Filed:
Sep. 12, 2007
Valery Tolstikhin, Ottawa, CA;
Kirill Pimenov, Ottawa, CA;
Valery Tolstikhin, Ottawa, CA;
Kirill Pimenov, Ottawa, CA;
Onechip Photonics, Ottawa, Ontario, CA;
Abstract
The invention describes the method and apparatus for enhancement of coupling efficiency in effective-ridge laterally-coupled surface-etched grating waveguide structures, where a slab waveguide has a sequence of the periodic parallel segmented trenches etched from its top surface, such that the segments of intact material having higher refractive index than that in the surrounding segments of periodic trenches form the effective ridges which confine the optical field in and around these ridges, on one hand, and provide bidirectional coupling for the confined modes experiencing Bragg reflection from the segments of the periodic trenches, on the other. The invention discloses the designs of the multiple effective ridge laterally coupled surface-etched grating waveguide structures, which enhances the coupling efficiency as compared to a conventional single effective ridge grating design because of an intended dilution of the lateral confinement caused by the multiple effective ridges, resulting in an increase of the optical mode's overlap with the surface etched grating formed everywhere outside the effective ridges.