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:
Aug. 16, 2005
Filed:
Oct. 28, 2004
Hiroshi Nagaeda, Sapporo, JP;
Nobuaki Mitamura, Sapporo, JP;
Kazuaki Akimoto, Sapporo, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
An optical device includes a small and low-cost variable polarization plane rotator that can control a rotation angle of the polarization plane easily. A variable polarization plane rotator is provided with a λ/4 phase plate having an optical axis in the same direction as, or at a 90 degree angle relative to, a polarization direction of an input light beam. A phase difference variable element has an optical axis at a ±45 degree angle relative to the optical axis of the λ/4 phase plate, to apply a variable phase difference between the polarization components parallel to and perpendicular to the optical axis thereof. A phase difference adjustment section adjusts the variable phase difference of the phase difference variable element, wherein the input light beam after being transmitted through the phase difference variable element to form elliptically polarized light or circularly polarized light, is transmitted through the λ/4 phase plate to form linearly polarized light. The polarization plane of the input light beam is rotated by an angle corresponding to the phase difference applied by the phase difference variable element.