Patent ID: 7365494
Filing Date: 2008-04-29
Classification: H01L

Abstract:
1. An active matrix type display device comprising: a pixel portion in which a plurality of pixels including a light-emitting element and a first thin film transistor for driving the light-emitting element are arranged in a matrix, a monitor element including a first electrode, an electroluminescent layer over the first electrode, and a second electrode over the electroluminescent layer; a second thin film transistor for driving the monitor element; a constant current source for applying current to the monitor element; and an amplifier, wherein the constant current source is electrically connected to one of a source and a drain of the second thin film transistor, wherein the other one of the source and the drain of the second thin film transistor is electrically connected to one of electrodes of the monitor element, wherein one of the electrodes of the light-emitting element is connected to an output of the amplifier with the first thin film transistor interposed therebetween, wherein the monitor element and the second thin film transistor are provided so as not to be overlapped with each other, wherein a first light shielding film is provided so as to be overlapped with a first electrode of the monitor element, and wherein a second light shielding film is provided so as to be overlapped with an edge of the first electrode.