A method of sensing an image from a panel for an image sensing circuit includes the steps of: transmitting a first voltage or current to the panel; receiving a plurality of sensing signals from the panel, wherein the plurality of sensing signals correspond to the first voltage or current; determining whether the plurality of sensing signals conform to an operation range of the image sensing circuit; and adjusting the first voltage or current when the plurality of sensing signals are determined to be not conform to the operation range of the image sensing circuit.