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:
Nov. 22, 2005
Filed:
Apr. 20, 2001
Tetsuo Sakanaka, Kanagawa, JP;
Tetsuo Sakanaka, Kanagawa, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An optical free-space communication apparatus includes a first light-emitting source for emitting a first transmission optical beam having a plane of polarization in a predetermined direction, the first transmission optical beam being modulated according to a primary signal containing communication information, a second light-emitting source for emitting a second transmission optical beam having a plane of polarization perpendicular to the plane of polarization of the first transmission optical beam, the second transmission optical beam being modulated according to an auxiliary signal for angle detection, a transmitting optical system for emitting the first and second transmission optical beams out of the apparatus as optical beams each having a predetermined angle of divergence, and a driving unit for redirecting the outgoing paths of the first and second transmission optical beams, wherein the second transmission optical beam has a larger angle of divergence than the first transmission optical beam.