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. 30, 2010
Filed:
Jul. 03, 2007
Takeshi Ueda, Kanagawa, JP;
Kohji Sakai, Tokyo, JP;
Yoshinori Hayashi, Kanagawa, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A multi-beam scanning device is disclosed that is able to realize a stable and small beam spot and realize stable scanning line intervals between plural light beams. The multi-beam optical scanning device includes a first optical system which has a first lens for coupling the light beams from the light sources, and a second lens which is an anamorphic element having power at least in a sub scanning direction and for guiding the light beams from the first lens to the deflection unit; and a second optical system. At least the second lens includes a diffracting surface having power. Magnifications of the whole optical system in a main scanning direction (βm) and in a sub scanning direction (βs), and a magnification of the second optical system (βs) in a sub scanning direction satisfy |βms, and |βss, and the power of the diffracting surface of the first lens in the main scanning direction (P), that in the sub scanning direction (P), and the power of the diffracting surface of the second lens in the sub scanning direction (P) satisfy |P|>|P| and |P|>|P