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:
Oct. 13, 1992
Filed:
Oct. 29, 1991
Katsumi Yamaguchi, Yokohama, JP;
Nobuo Sakuma, Inagi, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A scanning optical system has a light source for emitting a light beam; a condenser lens for changing the light beam from the light source to a parallel light beam; a connection holding member for supporting the light source and the condenser lens; a deflector for deflecting an approximately parallel light beam transmitted from the condenser lens at an equiangular velocity; and a lens for optical scanning for scanning a scanned face at an approximately equal speed while converging the light beam deflected by the deflector and forming an image in the shape of a spot on the scanned face, the lens for optical scanning being formed by a plastic material for optics. This scanning optical system is constructed such that a coefficient of linear expansion of the connection holding member, a focal length of the condenser lens, a focal length, a refractive index and a coefficient of linear expansion of the lens for optical scanning, and a change in refractive index of the lens for optical scanning with respect to the change in environmental temperature satisfy a predetermined condition. Another condition using other parameters with respect to the lens optical system may be set.