1. A method of operating an imaging system having an array of pixels arranged in rows and columns, wherein each pixel comprises four adjacent photosensitive areas located in two adjacent columns and two adjacent rows, and wherein each pixel comprises a microlens that covers the four adjacent photosensitive areas, the method comprising: generating image signals in the four adjacent photosensitive areas of each pixel; processing the image signals of each of the four adjacent photosensitive areas of a first pixel of the array of pixels to determine phase information, wherein only the image signals of each of the four adjacent photosensitive areas of the first pixel are used to determine the phase information, wherein processing the image signals of each of the four adjacent photosensitive areas of the first pixel to determine phase information comprises processing the image signals of each of the four adjacent photosensitive areas of the first pixel to detect vertical edges, horizontal edges, and diagonal edges, and wherein only the image signals of each of the four adjacent photosensitive areas of the first pixel are used to detect the vertical edges, horizontal edges, and diagonal edges; and processing the image signals of each of the four adjacent photosensitive areas of the first pixel to determine image information, wherein only the image signals of each of the four adjacent photosensitive areas of the first pixel are used to determine the image information, and wherein processing the image signals of each of the four adjacent photosensitive areas of the first pixel to determine the image information comprises averaging the image signals of each of the four adjacent photosensitive areas to obtain a single image signal value for the first pixel.