The present disclosure discloses an image sensor, an imaging method, an imaging device and an electronic device. The image sensor includes an array of photosensitive units, an array of filter units and an array of micro lenses, in which the array of photosensitive units includes focusing photosensitive units and non-focusing photosensitive units. With the image sensor, when a current ambient luminous intensity is smaller than a preset intensity, the image sensor generates an image with the first output mode, and when the current ambient luminous intensity is greater than the preset intensity, the image sensor generates an image with the second output mode. In addition, when the image sensor is used to focus, phase focusing may be performed according to output values of two parts of photosensitive pixels.