Image sensor including a pixel array having pixel blocks arranged in a zigzag form

An image sensor may include a pixel array including a plurality of pixel blocks structured to convert light into electrical signals. Each of the plurality of pixel blocks may include a first light receiving circuit including a plurality of unit pixels which share a first floating diffusion; a second light receiving circuit arranged adjacent to the first light receiving circuit in a second direction, and including a plurality of unit pixels which share a second floating diffusion; a first driving circuit and a second driving circuit positioned between the first light receiving circuit and the second light receiving circuit, and aligned in a first direction crossing the second direction; and an intercoupling circuit configured to electrically couple the first floating diffusion, the second floating diffusion, the first driving circuit and the second driving circuit.