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:
Feb. 09, 1993
Filed:
Feb. 09, 1990
Applicant:
Inventor:
Kenichi Ohta, Yokohama, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04N / ;
U.S. Cl.
CPC ...
358214 ; 358445 ; 358446 ; 382 58 ;
Abstract
An illuminator for applying light to an image, a reader for photoelectrically reading the light applied image, an amplifier for amplifying an analog signal outputted from the reader, an A/D converter for converting an analog signal outputted from the amplifier into a digital signal, a logarithmic transformer for logarithmically transforming the digital signal outputted from the A/D converter, a first controller for changing the logarithmic transformation of the logarithmic transformer, and a second controller for changing the gain of the digital signal in accordance with a change of the logarithmic transformation characteristic caused by the first controller.