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:
Sep. 23, 2008
Filed:
Mar. 25, 2004
Rainer Hainberger, Vienna, AT;
Shigeki Watanabe, Kawasaki, JP;
Rainer Hainberger, Vienna, AT;
Shigeki Watanabe, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A nonlinear birefringent waveguide is used for four wave mixing, wavelength conversion, Raman amplification, etc. In order to adjust the polarization of the input light to such waveguide, a polarization controlleris provided. And at the output side of the waveguide, a polarization beam splitter is provided. The polarization beam splitter splits one of orthogonal polarizations which is not desired to be passed through. The power of the split light is detected at photodiode. The detection signal of the photodiodeis fed back to the polarization controller. The polarization controllercontrols the polarization of input light so that the power of light detected at the photodiodeis minimized.