Image sensor, photographing method, and image-capturing device

Abstract

An image sensor includes: a plurality of microlenses arranged in a two-dimensional pattern; and a plurality of pixels that are provided in correspondence to each of the microlenses and receive lights of different color components, respectively. Pixels that are provided at adjacent microlenses among the microlenses and that receive lights of same color components, are adjacently arranged.

1 . An image sensor comprising:
 a plurality of microlenses arranged in a two-dimensional pattern; and   a plurality of pixels that are provided in correspondence to each of the microlenses and receive lights of different color components, respectively, wherein   pixels that are provided at adjacent microlenses among the microlenses and that receive lights of same color components, are adjacently arranged.   
     
     
         2 . An image sensor according to  claim 1 , wherein
 signals from the pixels are used both for focus detection and for generation of image data.   
     
     
         3 . An image sensor comprising:
 a plurality of microlenses arranged in a two-dimensional pattern; and   a plurality of pixels that are arranged in correspondence to each of the microlenses and receive lights having different color components, respectively, wherein   signals from the pixels are used both for focus detection and for generation of image data.   
     
     
         4 . A photographing method comprising:
 a focus detection step for performing focus detection, by using signals from particular pixels in an image sensor including a plurality of microlenses arranged in a two-dimensional pattern and a plurality of pixels that are arranged in correspondence to each of the microlenses and receive lights having different color components, the particular pixels receiving lights of same color components from different microlenses, respectively; and   a shooting step for generating a capture image by using signals from plurality of pixels provided in correspondence to each of the microlenses, the plurality of pixels receiving lights of different color components.   
     
     
         5 . A photographing method according to  claim 4 , wherein
 in the image sensor, pixels are provided at adjacent microlenses among the microlenses and that receive lights of same color components are adjacently arranged.   
     
     
         6 . An image-capturing device comprising:
 an image sensor that captures an image of a subject with light fluxes from the subject that have passed through an imaging optical system;   an image generation unit that generates an image signal based upon an output signal from the image sensor; and   a focus detection unit that detects a focusing condition of the imaging optical system by a phase detection method based upon an output signal from the image sensor, wherein   the image sensor includes a pixel group and a microlens group arranged so as to guide the light fluxes from the subject to the pixel group,   the pixel group includes first, second and third pixels having first, second and third spectral sensitivities, respectively, differing from each other, and being arranged in a two-dimensional pattern, with one of the first pixels, one of the second pixels and two of the third pixels being arranged in a two-by-two matrix behind each microlens in the microlens group, and the four pixels receive four light fluxes, respectively, that pass through four pupil areas, respectively, of an exit pupil of the imaging optical system,   the first, second, and third pixels are arranged such that pixels having substantially same spectral sensitivities are adjacently arranged in a two-by-two matrix and four pixels adjacent to the two-by-two matrix are arranged behind four different microlenses in the microlens group, respectively, and at different positions with respect to the microlenses,   the image generation unit generates the image signal based upon output signals from the first, second and third pixels, and   the focus detection unit detects the focusing condition based upon an output signal from at least one of the first, second, and third pixels.   
     
     
         7 . An image-capturing device according to  claim 6 , wherein
 the first pixel has a red color filter, the second pixel has a blue color filter, and the third pixel has a green color filter.   
     
     
         8 . An image-capturing device according to  claim 7 , wherein
 the pixel group includes an array of a plurality of sets of pixels arranged in a two-dimensional pattern, each of the plurality of sets of pixels having four pixels arranged in a two-by-two matrix behind any particular one of the microlenses and the sets include first through fourth sets having different arrangements of pixels,   in the first set, the first pixel and the third pixel are adjacently arranged in a predetermined array direction and the third pixel and the second pixel are arranged adjacent to the first pixel and the third pixel, respectively, in a direction perpendicular to the predetermined array direction,   in the second set, the third pixel and the first pixel are adjacently arranged in the predetermined array direction and the second pixel and the third pixel are arranged adjacent to the third pixel and the first pixel, respectively, in the direction perpendicular to the predetermined array direction,   in the third set, the third pixel and the second pixel are adjacently arranged in the predetermined array direction and the first pixel and the third pixel are arranged adjacent to the third pixel and the second pixel, respectively, in the direction perpendicular to the predetermined array direction,   in the fourth set, the second pixel and the third pixel are adjacently arranged in the predetermined array direction and the third pixel and the first pixel are arranged adjacent to the second pixel and the third pixel, respectively, in the direction perpendicular to the predetermined array direction,   the first set and the second set are adjacent to each other in the predetermined array direction and alternately arranged in a repeated manner in the predetermined array direction, the third set and the fourth set are adjacent to each other in the predetermined array direction and alternately arranged in a repeated manner in the predetermined array direction, and a first row formed by the first set and the second set and a second row formed by the third set and the fourth set are adjacent to each other in the direction perpendicular to the predetermined array direction and alternately arranged in a repeated manner in the direction perpendicular to the predetermined array direction.   
     
     
         9 . An image-capturing device according to  claim 7 , wherein
 the image generation unit adds output signals from four of the first pixels that are adjacent to each other in a form of a two-by-two matrix, adds output signals from four of the second pixels that are adjacent to each other in a form of a two-by-two matrix, and adds output signals from four of the third pixels that are adjacent to each other in a form of a two-by-two matrix to generate an image signal of a Bayer arrangement.   
     
     
         10 . An image-capturing device according to  claim 6 , wherein
 the image generation unit obtains three color signals at a position corresponding to each microlens based upon output signals from the first, second and third pixels arranged behind each microlens.   
     
     
         11 . An image-capturing device according to  claim 6 , wherein
 the image generation unit performs, at respective positions of the first through third pixels, color interpolation processing for generating signals of other two spectral components to obtain three color signals and generates a luminance signal and color difference signals based on the thus obtained three color signals.   
     
     
         12 . An image-capturing device according to  claim 6 , wherein
 the focus detection unit detects the focusing condition of the imaging optical system based upon output signals from a pair of pixels having substantially same spectral sensitivities and located at positions differing from each other with respect to the microlens, out of the pixel group.   
     
     
         13 . An image-capturing device according to  claim 8 , wherein
 the focus detection unit detects the focusing condition of the imaging optical system in the predetermined array direction based upon output signals from at least one plurality of the third pixels of a plurality of the third pixels contained in the first set and the second set, respectively, and a plurality of the third pixels contained in the third set and the fourth set, respectively.   
     
     
         14 . An image-capturing device according to  claim 8 , wherein
 the focus detection unit detects the focusing condition of the imaging optical system in the direction perpendicular to the predetermined array direction based upon output signals from at least one plurality of the third pixels of a plurality of the third pixels contained in the first set and the third set, respectively, and a plurality of the third pixels contained in the second set and the fourth set, respectively.   
     
     
         15 . An image-capturing device according to  claim 8 , wherein
 the focus detection unit detects the focusing condition of the imaging optical system in a direction oblique to the predetermined array direction based upon output signals from at least one plurality of the third pixels of a plurality of the third pixels contained in the first set and the fourth set, respectively, and a plurality of the third pixels contained in the second set and the third set, respectively.   
     
     
         16 . An image sensor comprising:
 a pixel group; and   a microlens group arranged so as to guide subject light fluxes to the pixel group, wherein   the pixel group includes first, second and third pixels having first, second and third spectral sensitivities, respectively, differing from each other, and being arranged in a two-dimensional pattern, with one of the first pixels, one of the second pixels and two of the third pixels being arranged in a two-by-two matrix behind each microlens in the microlens group, and the four pixels receive four light fluxes, respectively, that pass through four pupil areas, respectively, of an exit pupil of an imaging optical system,   the first, second, and third pixels are arranged such that pixels having substantially same spectral sensitivities are adjacently arranged in a two-by-two matrix, respectively, and four pixels adjacent to the two-by-two matrix are arranged behind four different microlenses of the microlens group, respectively, and at different positions with respect to the microlenses.