An active matrix display device which can easily improve the viewing angle characteristics. In the active matrix display device where light is emitted in the direction of a substrate over which thin film transistors are formed, when focusing on the multiple interference caused by the light emitted from a light-emitting element, which is reflected on the film used for forming the thin film transistors, effect on the multiple interference can be drastically reduced by forming the reflecting film to have the substantial optical thickness of .lamda./2, without losing the function of the thin film transistor.