Focus detection apparatus, image pickup device, and electronic camera

A focus detection apparatus, comprising:

• a plurality of first-type pixels, each first-type pixel including a photoelectric converter configured to receive light from an image-pickup optical system and perform photoelectric conversion, a light-collecting unit configured to collect incident light from the image-pickup optical system on the photoelectric converter, and an optical layer disposed on an optical path from the image-pickup optical system to the photoelectric converter, each first-type pixel outputting a first charge signal corresponding to an amount of light received by the photoelectric converter;
• a plurality of second-type pixels, each second-type pixel including the photoelectric converter, the light-collecting unit, and the optical layer disposed on the optical path from the image-pickup optical system to the photoelectric converter, each second-type pixel outputting a second charge signal corresponding to an amount of light received by the photoelectric converter;
• and
• an image-formation-state detector configured to detect an image formation state of the image-pickup optical system on the basis of the first charge signals and the second charge signals,
• wherein each of the first-type pixels and the second-type pixels further includes an optical member having an refractive index that is different from a refractive index of the optical layer,
• wherein the optical member included in each of the first-type pixels and the second-type pixels is disposed such that a peripheral edge of the optical member is separated from a straight line that passes through the center of the photoelectric converter along the optical axis direction of the image-pickup optical system and such that the optical member is opposed to only a part of the photoelectric converter, and
• wherein the optical member is disposed such that a position of one end of the optical member that is close to the straight line in each of the first-type pixels and a position of one end of the optical member that is close to the straight line in each of the second-type pixels are at the opposite sides of the straight line.

A focus detection apparatus, comprising:

• a plurality of first-type pixels, each first-type pixel including a photoelectric converter configured to receive light from an image-pickup optical system and perform photoelectric conversion and an optical member disposed on an optical path from the image-pickup optical system to the photoelectric converter such that the optical member is opposed to only a part of the photoelectric converter, the optical member having a laminated structure in which films made of optical materials having different refractive indices are stacked together, each first-type pixel outputting a first charge signal corresponding to an amount of light received by the photoelectric converter;
• a plurality of second-type pixels, each second-type pixel including the photoelectric converter and the optical member disposed on the optical path from the image-pickup optical system to the photoelectric converter such that a positional relationship between the optical member and the photoelectric converter differs from the positional relationship in each first-type pixel, each second-type pixel outputting a second charge signal corresponding to an amount of light received by the photoelectric converter;
• and
• an image-formation-state detector configured to detect an image formation state of the image-pickup optical system on the basis of the first charge signals and the second charge signals.

A focus detection apparatus, comprising:

• a plurality of first-type pixels, each first-type pixel including a photoelectric converter configured to receive light from an image-pickup optical system and perform photoelectric conversion, an optical layer disposed on an optical path from the image-pickup optical system to the photoelectric converter, a first waveguide disposed in the optical layer and having a refractive index that is higher than a refractive index of the optical layer, and a second waveguide disposed adjacent to the first waveguide in the optical layer and having a refractive index that is higher than the refractive index of the first waveguide, each first-type pixel outputting a first charge signal corresponding to an amount of light received by the photoelectric converter;
• a plurality of second-type pixels, each second-type pixel including the photoelectric converter, the optical layer disposed on the optical path from the image-pickup optical system to the photoelectric converter, and the first and second waveguides disposed adjacent to each other in the optical layer such that a positional relationship between the first and second waveguides and the photoelectric converter differs from the positional relationship in each first-type pixel, each second-type pixel outputting a second charge signal corresponding to an amount of light received by the photoelectric converter;
• and
• an image-formation-state detector configured to detect an image formation state of the image-pickup optical system on the basis of the first charge signals and the second charge signals.

An image pickup device, comprising:

• a plurality of first-type pixels, each first-type pixel including a photoelectric converter, a first optical member, and a second optical member, the photoelectric converter being configured to receive light from an image-pickup optical system and perform photoelectric conversion, the first and second optical members being arranged on an optical path from the image-pickup optical system to the photoelectric converter and having different refractive indices, each first-type pixel outputting a first charge signal corresponding to an amount of light received by the photoelectric converter;
• a plurality of second-type pixels, each second-type pixel including the photoelectric converter, the first optical member, and the second optical member, the first and second optical members being arranged on the optical path from the image-pickup optical system to the photoelectric converter such that a positional relationship between the first and second optical members and the photoelectric converter differs from the positional relationship in each first-type pixel, each second-type pixel outputting a second charge signal corresponding to an amount of light received by the photoelectric converter;
• and
• a plurality of image pickup pixels, each image pickup pixel including the photoelectric converter and outputting a third charge signal corresponding to an amount of light received by the photoelectric converter.

An electronic camera, comprising:

• a plurality of first-type pixels, each first-type pixel including a photoelectric converter, a first optical member, and a second optical member, the photoelectric converter being configured to receive light from an image-pickup optical system and perform photoelectric conversion, the first and second optical members being arranged on an optical path from the image-pickup optical system to the photoelectric converter and having different refractive indices, each first-type pixel outputting a first charge signal corresponding to an amount of light received by the photoelectric converter;
• a plurality of second-type pixels, each second-type pixel including the photoelectric converter, the first optical member, and the second optical member, the first and second optical members being arranged on the optical path from the image-pickup optical system to the photoelectric converter such that a positional relationship between the first and second optical members and the photoelectric converter differs from the positional relationship in each first-type pixel, each second-type pixel outputting a second charge signal corresponding to an amount of light received by the photoelectric converter;
• a plurality of image pickup pixels, each image pickup pixel including the photoelectric converter and outputting a third charge signal corresponding to an amount of light received by the photoelectric converter;
• a signal processor configured to generate image data on the basis of the third charge signals;
• an image-formation-state detector configured to detect an image formation state of the image-pickup optical system on the basis of the first charge signals and the second charge signals;
• and
• a focus controller configured to adjust a lens position of the image-pickup optical system such that the lens position approaches an in-focus position on the basis of the image formation state determined by the image-formation-state detector.