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. 26, 1993
Filed:
Mar. 23, 1992
Applicant:
Inventors:
Fumio Suzuki, Yokohama, JP;
Yoshinari Hamanishi, Wako, JP;
Assignee:
Nikon Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B / ; G02B / ;
U.S. Cl.
CPC ...
359771 ; 359684 ; 359686 ;
Abstract
A lens for an underwater camera is comprised of a first lens unit having no refractive power or having weak refractive power, a second lens unit comprising a forward unit having negative refractive power and a rearward unit having positive refractive power, and having weak refractive power, a third lens unit having positive refractive power, and a fourth lens unit having negative refractive power, the first lens unit being fixed relative to the image plane, the second lens unit and the third lens unit being axially moved together on the optical axis toward the object side relative to the fourth lens unit.