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:
May. 05, 2009
Filed:
Sep. 06, 2005
Mario Martinelli, San Donato Milanese, IT;
Paolo Martelli, Milan, IT;
Silvia Maria Pietralunga, Cassina de' Pecchi, IT;
Aldo Righetti, Milan, IT;
Mario Martinelli, San Donato Milanese, IT;
Paolo Martelli, Milan, IT;
Silvia Maria Pietralunga, Cassina de' Pecchi, IT;
Aldo Righetti, Milan, IT;
PGT Photonics S.p.A., Milan, IT;
Abstract
A polarization stabilizing device and method based on controlling the phase retardations of a pair of variable rotators with an optically interposed quarter-wave plate, with a controller such that the first of the variable rotators has its phase retardation switched between first and second values whenever the phase retardation of the second of the variable rotators reaches an upper or a lower limit. The upper and lower limits of the second rotator and the first and second values of the first rotator are chosen so that discontinuities in the power of the output optical radiation are avoided when the first variable rotator is switched, thereby providing endless polarization stabilization using rotators that themselves may have limited retardation ranges.