Radiant energy – Photocells; circuits and apparatus – Photocell controls its own optical systems
Patent
1987-07-07
1989-05-23
Westin, Edward P.
Radiant energy
Photocells; circuits and apparatus
Photocell controls its own optical systems
250204, 254404, G01J 120
Patent
active
048333131
ABSTRACT:
An apparatus for detecting the focus state of an optical system has optical apparatus for forming first and second light distributions of an object. The relative positional relationship of the light distributions varies in accordance with the focus state of the optical system. A light receiving device has first and second ranges, each having a plurality of picture elements. The first and second ranges respectively receive the first and second light distributions. Operation circuitry manipulates the output signals from the first and second ranges by relatively mathematically moving them to calculate a value representing the focus state of the optical system. The operation circuitry selectively executes a first operation in which the number of signals corresponding to each other is varied, and a second operation in which the number of signals corresponding to each other is kept constant.
REFERENCES:
patent: 4532420 (1985-07-01), Nakajima
patent: 4535231 (1985-08-01), Tanaka
patent: 4559446 (1985-12-01), Suzuki
patent: 4636624 (1987-01-01), Ishida et al.
Akashi Akira
Ishizaki Akira
Koyama Takeshi
Ohnuki Ichiro
Ohtaka Keiji
Canon Kabushiki Kaisha
Shami Khaled
Westin Edward P.
LandOfFree
Focus detecting apparatus having increased SNR by selectively va does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Focus detecting apparatus having increased SNR by selectively va, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Focus detecting apparatus having increased SNR by selectively va will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1731954