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. 08, 1991
Filed:
Jan. 03, 1990
Applicant:
Inventors:
Yasutaka Maeda, Ikoma, JP;
Natsuko Tanaka, Nara, JP;
Katsuhiro Nagayama, Yamatokoriyama, JP;
Hideyuki Nishimura, Yamatokoriyama, JP;
Assignee:
Sharp Kabushiki Kaisha, Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G03G / ;
U.S. Cl.
CPC ...
355214 ; 355 71 ; 355246 ; 355326 ;
Abstract
A copying apparatus in which a screen for improving gradation characteristics of a copied image can be retractably projected into an optical path, including a device for setting, when the screen is placed in the optical path and retracted from the optical path, a developing voltage to a first value and a second value, respectively such that the first value is lower than the second value.