Focus detection device and image-capturing apparatus

Abstract

A focus detection device includes: a plurality of first pixels having first color filters, via which a pair of first signals, to be used for split-pupil phase detection, are output; a plurality of second pixels having second color filters, via which a pair of second signals, to be used for the split-pupil phase detection, are output; a phase difference detection unit that detects a phase difference manifested by the first signals or a phase difference manifested by the second signals; and a defocus amount calculation unit that calculates a defocus amount by using a first conversion coefficient corresponding to the first color when the phase difference detection unit has detected the phase difference manifested by the first signals and by using a second conversion coefficient corresponding to the second color when the phase difference detection unit has detected the phase difference manifested by the second signals.

1 . A focus detection device, comprising:
 an image sensor that includes:
 a plurality of first pixels each receiving first color light, which is part of light having passed through an optical system including a focusing lens, and outputting a plurality of first signal; and 
 a plurality of second pixels each receiving second color light, which is part of light having passed through the optical system, and outputting a plurality of second signals; and 
   a microcomputer configured to store a first value used for calculating a value related to driving the focusing lens based upon the plurality of first signals and a second value used for calculating the value related to driving the focusing lens based upon the plurality of second signals.   
     
     
         2 . (canceled) 
     
     
         3 . (canceled) 
     
     
         4 . The focus detection device according to  claim 1 , wherein:
 the microcomputer calculates the value related to driving the focusing lens based upon an output value related to the plurality of first signals, which is greater than an output value related to the plurality of second signals.   
     
     
         5 . The focus detection device according to  claim 1 , wherein:
 the microcomputer calculates the value related to driving the focusing lens based upon the plurality of first signals and calculates the value related to driving the focusing lens based upon the plurality of second signals.   
     
     
         6 . The focus detection device according to  claim 1 , wherein:
 the value related to driving the focusing lens is based upon a deviation of a plane on which an image is formed by the optical system, relative to an image-capturing plane of the image sensor.   
     
     
         7 . The focus detection device according to  claim 1 , wherein:
 the value related to driving the focusing lens corresponds to a drive amount indicating an extent to which the focusing lens is to be driven for an image formed by the optical system in order to be in focus on an image-capturing plane of the image sensor.   
     
     
         8 . A camera, comprising
 the focus detection device according to  claim 1 .   
     
     
         9 . A focus detection device, comprising:
 an image sensor that includes:
 a plurality of first pixels each receiving light, which is passing through a first color filter and is part of light having passed through an optical system including a focusing lens, and outputting a plurality of first signals; and 
 a plurality of second pixels each receiving light, which is passing through a second color filter and is part of light having passed through the optical system, and outputting a plurality of second signals; and 
   a microcomputer configured to store a first value used for calculating a value related to driving the focusing lens based upon the plurality of first signals and a second value used for calculating the value related to driving the focusing lens based upon the plurality of second signals.   
     
     
         10 . The focus detection device according to  claim 9 , wherein:
 the plurality of first pixels and the plurality of second pixels of the image sensor are set at alternate positions along a direction.   
     
     
         11 . The focus detection device according to  claim 9 , wherein:
 the plurality of first pixels of the image sensor are set consecutively along a direction.   
     
     
         12 . The focus detection device according to  claim 9 , wherein:
 the microcomputer calculates the value related to driving the focusing lens based upon either the plurality of first signals or the plurality of second signals.