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. 03, 2001
Filed:
Jul. 23, 1998
Arnold Peter Roscoe Harpin, Oxford, GB;
Andrew George Rickman, Marlborough, GB;
Bookham Technology PLC, Oxfordshire, GB;
Abstract
The present invention is a temperature stable integrated optical device which is substantially insensitive to temperature variations. The device, such as an interferometer, includes sub-sections of a different light transmissive material within the optical pathways. The relative lengths of the two different material waveguides can be selected so as to achieve temperature insensitivity. A suitable balance is to ensure that the ratio of the difference in sub-path lengths of the first and second materials is equal to the ratio of the refractive index gradient with temperature of the second material to the refractive index gradient with temperature of the first material. Preferable materials are silicon and silicon nitride.