A light emitting device comprising: an electroluminescent element; a first transistor; a second transistor; a third transistor including a gate electrode, a first electrode, and a second electrode; a capacitor; a gate line; a first line being a source signal line; and a second line being a current supply line, wherein the first transistor includes a gate electrode, a first electrode, and a second electrode; wherein the second transistor includes a gate electrode, a first electrode, and a second electrode; wherein the gate electrode of the first transistor is electrically connected to the gate line, wherein the first electrode of the first transistor is electrically connected to the first line, wherein the second electrode of the first transistor is electrically connected to the capacitor, wherein the second electrode of the first transistor is electrically connected to the gate electrode of the second transistor; wherein the first electrode of the second transistor is electrically connected to the electroluminescent element; wherein the capacitor is electrically connected to the electroluminescent element; wherein the second electrode of the second transistor is electrically connected to the second line, wherein the capacitor is electrically connected between the first electrode and the gate electrode of the second transistor; and wherein the first electrode of the second transistor is connected to the first electrode of the third transistor and a first electrode of the electroluminescent element, the gate electrode of the third transistor is connected to the gate line, and the second electrode of the third transistor is connected to a power source line while a second electrode of the electroluminescent element is connected to a further power line. an electroluminescent element; a first transistor; a second transistor; a third transistor including a gate electrode, a first electrode, and a second electrode; a capacitor; a gate line; a first line being a source signal line; and a second line being a current supply line, wherein the first transistor includes a gate electrode, a first electrode, and a second electrode; wherein the second transistor includes a gate electrode, a first electrode, and a second electrode; wherein the gate electrode of the first transistor is electrically connected to the gate line, wherein the first electrode of the first transistor is electrically connected to the first line, wherein the second electrode of the first transistor is electrically connected to the capacitor, wherein the second electrode of the first transistor is electrically connected to the gate electrode of the second transistor; wherein the first electrode of the second transistor is electrically connected to the electroluminescent element; wherein the capacitor is electrically connected to the electroluminescent element; wherein the second electrode of the second transistor is electrically connected to the second line, wherein the capacitor is electrically connected between the first electrode and the gate electrode of the second transistor; and wherein the first electrode of the second transistor is connected to the first electrode of the third transistor and a first electrode of the electroluminescent element, the gate electrode of the third transistor is connected to the gate line, and the second electrode of the third transistor is connected to a power source line while a second electrode of the electroluminescent element is connected to a further power line.