An image sensor includes a pair of pixel sharing circuits, a second reset transistor, an amplifier transistor, a readout transistor and a control circuit. The pair of pixel sharing circuits connected to a floating diffusion node, each including a photon device, a first reset transistor, a capture transistor, a holding transistor, a capacitor and a sharing transistor. The control circuit is configured to control the first reset transistor, the first capture transistor, the first holding transistor and the sharing transistor of each of the pair of sharing pixel circuits to be turned on or off.