Back to results
US 7,746,403 B2Granted
Image capturing apparatus having a plurality of focus detention devices and control method therefor
AssigneeCanon Kabushiki Kaish
InventorHirofumi Suda
Life of this patent
Estimating the term…
Abstract
This invention allows focus detection devices to be smoothly and quickly switched even if different image capturing frame counts or image capturing field counts are set in accordance with image capturing purposes. An AF system selection unit switches focus detection methods based on a direct distance measurement AF unit and captured signal AF detection unit in accordance with the frame count or field count of a captured signal.
Claims9
An image capturing apparatus comprising:
- an image capturing device which outputs a captured signal of an object on the basis of incident light;
- an output interval control device which variably controls output intervals of captured signals output by said image capturing device per unit time;
- a plurality of focus detection devices which detect a focus;
- and
- a control device which controls focus detection by said plurality of focus detection devices;
- and
- a focusing degree calculating device which calculates a focusing degree on the basis of a captured signal output from said image capturing device,
- wherein said plurality of focus detection devices include a first focus detection device performing a focus detection based on a distance measurement result and a second focus detection device performing a focus detection based on a high frequency component of a captured signal,
- wherein said control device compares a focusing degree calculated by said focusing degree calculating device with a predetermined focusing degree, and choosing a timing for switching from said first focus detection device to said second focus detection device in accordance with a comparison result, and
- wherein said control device sets a first predetermined focusing degree as a comparison target for a focusing degree calculated by said focusing degree calculating device when captured signal output intervals are first predetermined output intervals, and sets a second predetermined focusing degree nearer to an in-focus point than the first predetermined focusing degree as a comparison target for a focusing degree calculated by said focusing degree calculating device when captured signal output intervals are second predetermined output intervals longer than the first predetermined output intervals.
7 more elements
A control method for an image capturing apparatus including an image capturing device which outputs a captured signal of an object on the basis of incident light, and a plurality of focus detection devices which detect a focus state, comprising:
- an output interval control step of variably controlling output intervals of captured signals output by the image capturing device per unit time;
- and
- a control step of controlling focus detection by said plurality of focus detection devices;
- and
- a focusing degree calculating step of calculating a focusing degree on the basis of a captured signal output from said image capturing device,
- wherein said plurality of focus detection devices include a first focus detection device performing a focus detection based on a distance measurement result and a second focus detection device performing a focus detection based on a high frequency component of a captured signal,
- wherein said control step compares a focusing degree calculated by said focusing degree calculating step with a predetermined focusing degree, and chooses a timing for switching from said first focus detection device to said second focus detection device in accordance with a comparison result, and
- wherein said control step sets a first predetermined focusing degree as a comparison target for a focusing degree calculated by said focusing degree calculating step when captured signal output intervals are first predetermined output intervals, and sets a second predetermined focusing degree nearer to an in-focus point than the first predetermined focusing degree as a comparison target for a focusing degree calculated by said focusing degree calculating step when captured signal output intervals are second predetermined output intervals longer than the first predetermined output intervals.
5 more elements
Dependencies are inferred from the claim text.