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. 12, 2002
Filed:
May. 21, 1998
Hiroto Ohkawara, Ibaraki-ken, JP;
Masahide Hirasawa, Kanagawa-ken, JP;
Taeko Tanaka, Kanagawa-ken, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A lens control device comprising a variator lens group for zooming, a focusing lens group for compensating for a change introduced into the focused position as a result of a zooming operation by the variator lens group, a conversion lens group for changing a focusable shifting area of the variator lens group from a first area to a second area, a computing circuit for determining driving information for driving the focusing lens group during the shifting of the variator lens group, based on focused position data, according to object distance, of the focusing lens group relative to the position of the variator lens group, and a control circuit for shifting the variator lens group from the first area to the second area in response to the mounting of the conversion lens group and for controlling a computing operation of the computing circuit so that a focused position of the focusing lens group is determined when the variator lens group moves within the second area.