Abstract: An image sensor for on-chip phase detection includes a pixel array for capturing an image of a scene, wherein the pixel array has a plurality of horizontal phase-detection rows, each including phase-detection pixels for detecting horizontal change in the scene, and a plurality of vertical phase-detection columns, each including phase-detection pixels for detecting vertical change in the scene, and wherein each of the horizontal phase-detection rows intersects each of the vertical phase-detection columns. A phase-detection method includes generating a pair of horizontal line profiles using one of a plurality of phase-detection rows; generating a pair of vertical line profiles using one of a plurality of phase-detection columns intersecting with the one of a plurality of phase-detection rows; and determining phase shift associated with at least one arbitrarily oriented edge in a scene, based upon the pair of horizontal line profiles and the pair of vertical line profiles.