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. 15, 2001
Filed:
Dec. 21, 1999
Ricoh Company Ltd., Tokyo, JP;
Abstract
An optical scanning device includes a light source, a coupling lens, an optical deflector, an aperture and a scanning image-forming optical system. The central wavelength of the light flux emitted by the light source is less than about 680 nm, and NAO, &kgr;, &bgr;,satisfy &bgr;,/(NAO•&kgr;)<100, and NAO satisfies 0.18<NAO<0.35, where: NAO represents the light-source-side numerical aperture of the coupling lens; &kgr; represents the ratio A/D of the larger diameter A of the diameters, in a main scanning direction and a sub-scanning direction, of the opening of the aperture relative to the diameter D of the light flux emitted from the coupling lens; and &bgr;,represents the larger one of the lateral magnifications, in the main scanning direction and the sub-scanning direction, of the entire optical system with respect to an optical path extending from the light source to the surface to be scanned, and including a point of the image surface, at which point the image height is 0.