Title:
【発明の名称】光量制御装置および光量制御装置を有する光学機器
Document Type and Number:
Japanese Patent JP2571982
Kind Code:
B2
Abstract:
PURPOSE:To always apply proper speed control to a magnet rotor 25 to control a change in a light quantity. CONSTITUTION:A light quantity control signal passes a differential coil 21 and a power amplifier 22, and is inputted to a driving coil 24, the magnetic rotor 25 is rotated, and its rotational position is detected by a magnetic induction element 27. The output of the magnetic induction element 27 is inputted into a function generator 30 as a determined position detecting signal, through a differential amplifier 28, this signal is converted into a linear position detecting signal in proportion to the changing ratio of an aperture area and outputted as a diaphragm value detecting signal.
Inventors:
SATO OSAMU
Application Number:
JP41908290A
Publication Date:
January 16, 1997
Filing Date:
December 25, 1990
Export Citation:
Assignee:
CANON DENSHI KK
International Classes:
G03B7/10; G03B7/095; G03B9/02; H04N5/238; (IPC1-7): G03B7/095; G03B9/02; H04N5/238
Domestic Patent References:
| JP466921A |
Attorney, Agent or Firm:
Takaharu Takita