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:
Mar. 20, 2001
Filed:
Jul. 28, 1999
Applicant:
Inventors:
Takeshi Akiyama, Yokohama, JP;
Keisuke Araki, Yokohama, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B 1/700 ; G02B 2/100 ;
U.S. Cl.
CPC ...
G02B 1/700 ; G02B 2/100 ;
Abstract
An optical system in which rays of light from an object pass through includes a first lens unit having at least one off-axial curved surface, a second lens unit and a third lens unit having at least one off-axial curved surface in the named order and wherein chiefly the first lens unit and the third lens unit cancel aberrations created by the off-axial curved surfaces with each other so that totally good aberration correction may be effected.