To ensure focus detection performance of high precision by a focus-detecting pixel, while ensuring the high pixelation of an imaging element, reduction in chip size and improved image quality by pixel-size reduction in an imaging pixel.

The pixel size of a focus-detecting pixel 311, which is arranged in an imaging element 212, is made equal to that of four imaging elements 310, to ensure focus detection performance. The focus-detecting pixel 311 is arranged obliquely in a 45° direction on the imaging element 212 to ensure many peripheral imaging pixels 212 which are used for complementing image data at the position of the focus-detecting pixel 311. Accordingly, deterioration in the image quality which is caused, accompanying the pixel size of the focus-detecting pixel 311 being made larger than that of the imaging pixel 310 is prevented.