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:
Jan. 31, 1989
Filed:
Feb. 22, 1988
Herbert J Shaw, Stanford, CA (US);
Robert C Youngquist, Mountain View, CA (US);
Janet L Brooks, Mountain View, CA (US);
The Board of Trustees of the Leland Stanford Junior University, Stanford, CA (US);
Abstract
There is disclosed herein a fiber optic directional coupler for coupling light between two polarization modes. A highly birefringent fiber optic waveguide is positioned on a flat polished surface with either of the principal axes of birefringence oriented at an angle, preferably 45.degree., to the vertical. A ridged block is then pressed down on the fiber. The ridges of the block have longitudinal axes transverse to the longitudinal axis of the fiber. The width of the ridge faces is one-half beat length, and the spacing between the ridges in also one-half beat length. The stressed regions caused by the ridges cause coupling of light traveling in one polarization mode into the other polarization mode by abrupt shifting of the axes of birefringence at the boundaries of the stressed regions.