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:
Dec. 26, 1989
Filed:
Jul. 15, 1988
Ekkehard Klement, Graefelfing, DE;
Hartmut Schneider, Munich, DE;
Holger Karstensen, Munich, DE;
Helmut Zrschizky, Munich, DE;
Siemens Aktiengesellschaft, Berlin and Munich, DE;
Abstract
A birefringent optical waveguide structure comprises at least one or more strip waveguides of a first material embedded in a cladding layer of a second glass with at least one additional layer being applied on the cladding layer. The strip waveguides have a refractive index which is higher than the refractive index of the second glass of the cladding layers and the additional layer applies a mechanical stress to the strip waveguides which has a component extending perpendicular to the strip waveguides. Preferably, the mechanical stress is formed by the material of the additional layers having a different thermal expansion coefficient and a different elasto-optical coefficient than the materials forming the cladding layer and the strip waveguides. The method of forming the device includes rapidly cooling the structure from an elevated temperature to room temperature to create the mechanical stresses.