| US 7,570,298 B2 | ||
| Image-taking apparatus with first focus control such that in-focus position is searched for based on first signal and second focus control such that one of in-focus position and drive amount is determined based on second signal | ||
| Hitoshi Yasuda, Tokyo (Japan) | ||
| Assigned to Canon Kabushiki Kaisha, Tokyo (Japan) | ||
| Filed on Aug. 03, 2004, as Appl. No. 10/909,404. | ||
| Claims priority of application No. 2003-317340 (JP), filed on Sep. 09, 2003. | ||
| Prior Publication US 2005/0052563 A1, Mar. 10, 2005 | ||
| Int. Cl. H04N 5/232 (2006.01); G03B 13/00 (2006.01); G03B 3/00 (2006.01) | ||
| U.S. Cl. 348—345 [348/350; 396/102] | 5 Claims |
| 1. An image-taking apparatus comprising:
an image-pickup device which photoelectrically converts an object image formed by an image-taking optical system including
a focus lens;
a first detector which outputs a first signal representing a focus state of the image-taking optical system based on a predetermined-frequency
component of an output signal of the image-pickup device;
a second detector which outputs a second signal corresponding to a defocus amount of the image-taking optical system based
on phase difference of two images; and
a controller which performs a first focus control for controlling drive of the focus lens such that an in-focus position of
the focus lens is searched for based on the first signal and a second focus control for controlling drive of the focus lens
such that one of an in-focus position and a drive amount of the focus lens is determined based on the second signal,
wherein the controller selects the first focus control in priority over the second focus control in a case where a value of
the first signal is larger than a predetermined value, and
wherein, in a case where the second focus control is selected, the controller changes the predetermined value into a value
smaller than that at the time of the selection of the second focus control.
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