Title:
駆動装置、光量調節装置及びレンズ駆動装置
Document Type and Number:
Japanese Patent JP4164297
Kind Code:
B2
Abstract:
A driving apparatus includes a rotatable rotor with a ring shape, a first magnetic pole portion, a second magnetic pole portion, and a coil for magnetically exciting the first magnetic pole portion and the second magnetic pole portion. The rotor has magnet portions which are divided along a circumferential direction and differently magnetized. The coil is disposed radially of the rotor. The condition of -0.333X+0.7>Y is satisfied where Y is a ratio of a central angle of each first magnetic pole portion relative to a central angle of each magnetized pole in the magnet portion, and X is a ratio of an outer circumferential length of each magnetized pole in the magnet portion relative to a thickness of the magnet portion in a direction of the rotational axis.
Inventors:
Miyawaki Makoto
Application Number:
JP2002202171A
Publication Date:
October 15, 2008
Filing Date:
July 11, 2002
Export Citation:
Assignee:
Canon Inc
International Classes:
G03B9/02; G03B9/04; G03B9/06; G03B9/10; G03B9/14; G03B9/22; G03B11/00; H02K7/14; H02K21/14; H02K21/24; H02K26/00; H04N5/232
Domestic Patent References:
| JP62050715A | ||||
| JP62080636A | ||||
| JP6242489A | ||||
| JP2002051524A | ||||
| JP2002116478A |
Attorney, Agent or Firm:
Minoru Nakamura