Focus detection device and imaging apparatus having the same

[0034]FIG. 1 is a view showing an example of the arrangement of a digital camera as an example of an imaging apparatus to which a focus detection device according to the first embodiment of the present invention is applicable.

[0035]A first lens group 101 is arranged on the first stage of a photographing optical system (image forming optical system), and held to be movable along the optical axis. A shutter 102 functions as a shutter for controlling the exposure time in still image shooting, and also a stop for adjusting the light quantity in shooting by adjusting the aperture diameter. A second lens group 103 arranged behind the shutter 102 (on the image sensor side) can move along the optical axis together with the shutter 102, and provides a zoom function together with the first lens group 101.

[0036]A third lens group 105 is a focus lens, and can move along the optical axis. An optical low-pass filter 106 is arranged in front of an image sensor 107, and reduces a false color and mo...

[0132]In the first embodiment, a member which limits a light flux in the pupil-divided direction in a focus-detecting pixel is formed using the first electrode group 154 closer to the focus position of the microlens 162 out of the first and second electrode groups 154 and 155 having different distances from the focus position of the microlens 162. A member which limits a light flux in a direction perpendicular to the pupil-divided direction in a focus-detecting pixel is formed using the second electrode group 155 farther from the focus position of the microlens 162 than the first electrode group 154.

[0133]To the contrary, in the second embodiment, members which limit light fluxes in the pupil-divided direction and a direction perpendicular to it are formed by the first electrode group 154 without using the second electrode group 155.

[0134]FIG. 17 is an enlarged plan view of 8×8=64 pixels included in a unit block in an image sensor which forms a focus detection device according to th...