Title:
LENS CONTROLLER
Document Type and Number:
Japanese Patent JP3270493
Kind Code:
B2
Abstract:
PURPOSE: To provide the zoom lens controller which performs accurate automatic focus adjustment by following up a correct cam track even when photography having plural subject distances is started while a zoom lens is at a wide-angle end, etc., and a focus lens is at a position in depth of focus.
CONSTITUTION: The lens controller is equipped with a 1st lens group 102 which varies the power, a 2nd lens group 105 for focus adjustment, a 1st power varying means which maintains an in-focus state by correcting the displacement of a focal plane due to the movement of the 1st lens group by controlling the 2nd lens group, a storage means stored with relative position information on the 2nd lens group about the 1st lens group during the power varying operation by the 1st power varying means, and a 2nd power varying means which controls the 2nd lens group at the time of the movement of the 1st lens group according to the data stored in the storage means, and a system control circuit 119 performs general control over them.
Inventors:
Masahide Hirasawa
Application Number:
JP20764491A
Publication Date:
April 02, 2002
Filing Date:
August 20, 1991
Export Citation:
Assignee:
Canon Inc
International Classes:
G02B7/08; G02B7/10; G02B7/105; H04N5/232; (IPC1-7): G02B7/10; G02B7/08; G02B7/105; H04N5/232
Domestic Patent References:
| JP2293708A | ||||
| JP6262313A | ||||
| JP1321416A |
Attorney, Agent or Firm:
Suguru Kato