Title:
焦点検出装置
Document Type and Number:
Japanese Patent JP5820137
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a focus detector capable of adjusting a focus with high accuracy even on a subject with very high luminance while downsizing the circuit of the focus detector.SOLUTION: There is provided a focus detector which detects a focus based on signals obtained from a plurality of line sensors that receive light from a subject to accumulate charges. The focus detector comprises: a plurality of sensor blocks each of which comprises the plurality of line sensors; a plurality of comparators that correspond to the plurality of sensor blocks and monitor the signals from the line sensors by cyclically accessing each of the line sensors at a predetermined cycle for each of the sensor blocks; and control means that, when a maximum value of the monitored signals from the line sensors is greater than a predetermined value, stops the line sensor from accumulating the charges, so that the maximum value of the signals of the plurality of line sensors obtained with the accumulation of the charges during one cycle of monitoring by each of the comparators is lower than the predetermined value.
Inventors:
Takayuki Zhou
Application Number:
JP2011076394A
Publication Date:
November 24, 2015
Filing Date:
March 30, 2011
Export Citation:
Assignee:
Canon Inc
International Classes:
G02B7/28; G02B7/34; G03B13/36; H04N5/232
Domestic Patent References:
| JP2006039397A | ||||
| JP3041407A | ||||
| JP2002131630A | ||||
| JP10108060A |
Attorney, Agent or Firm:
Yasunori Otsuka
Shiro Takayanagi
Yasuhiro Otsuka
Shuji Kimura
Osamu Shimoyama
Nagakawa Yukimitsu
Shiro Takayanagi
Yasuhiro Otsuka
Shuji Kimura
Osamu Shimoyama
Nagakawa Yukimitsu