Light emitting element and light emitting device using the element

A light emitting device comprising:

• a thin film transistor over a substrate, the thin film transistor comprising:
• a semiconductor film over the substrate;
• an insulating film adjacent to the semiconductor film;
• and
• a gate electrode adjacent to the semiconductor film with the insulating film interposed therebetween;
• a first light emitting element having a first light emitting layer including a light emitting organic compound between a first anode and a first cathode;
• a second light emitting element having a second light emitting layer including a light emitting organic compound between a second anode and a second cathode;
• and
• a color filter,
• wherein the first light emitting element and the second light emitting element are connected in series and are electrically connected to the thin film transistor,
• wherein the first light emitting element shows a first emission color including two kinds of emission colors having a complementary color relationship and the second light emitting element shows a second emission color different from the two kinds of emission colors,
• wherein a white emission color is shown by the first emission color and the second emission color, and
• wherein the color filter is arranged to change a chromaticity of the white emission color.

A light emitting device comprising:

• a thin film transistor over a substrate, the thin film transistor comprising:
• a semiconductor film over the substrate;
• an insulating film adjacent to the semiconductor film;
• and
• a gate electrode adjacent to the semiconductor film with the insulating film interposed therebetween;
• a first light emitting element having a first light emitting layer including a light emitting organic compound between a first anode and a first cathode;
• and
• a second light emitting element having a second light emitting layer including a light emitting organic compound between a second anode and a second cathode;
• and
• a color filter,
• wherein the first light emitting element and the second light emitting element are connected in series and are electrically connected to the thin film transistor,
• wherein the first light emitting element shows a first emission spectrum having peaks in a blue to blue green wavelength range and in a yellow to orange wavelength range and the second light emitting element shows a second emission spectrum having a peak in a different position from positions of the peaks,
• wherein a white emission color is shown by the first emission spectrum and the second emission spectrum, and
• wherein the color filter is arranged to change a chromaticity of the white emission color.

A light emitting device comprising:

• a thin film transistor over a substrate, the thin film transistor comprising:
• a semiconductor film over the substrate;
• an insulating film adjacent to the semiconductor film;
• and
• a gate electrode adjacent to the semiconductor film with the insulating film interposed therebetween;
• a first light emitting element having a first light emitting layer including a light emitting organic compound between a first anode and a first cathode;
• a second light emitting element having a second light emitting layer including a light emitting organic compound between a second anode and a second cathode;
• and
• a color filter,
• wherein the first light emitting element and the second light emitting element are connected in series and are electrically connected to the thin film transistor,
• wherein the first light emitting element shows a first emission spectrum having peaks in a wavelength range from 430 nm to 480 nm and in a wavelength range from 550 nm to 600 nm and the second light emitting element shows a second emission spectrum having a peak in a different position from positions of the peaks,
• wherein a white emission color is shown by the first emission spectrum and the second emission spectrum, and
• wherein the color filter is arranged to change a chromaticity of the white emission color.

A lighting device comprising:

• a first light emitting element having a first light emitting layer including a light emitting organic compound;
• and
• a second light emitting element having a second light emitting layer including a light emitting organic compound,
• wherein the first light emitting element and the second light emitting element are connected in series,
• wherein the first light emitting layer and the second light emitting layer are overlapped with each other, and
• wherein the first light emitting layer comprises a third light emitting layer and a fourth light emitting layer which shows a different emission color from an emission color of the third light emitting layer.

A lighting device comprising:

• a first light emitting element having a first light emitting layer including a light emitting organic compound;
• and
• a second light emitting element having a second light emitting layer including a light emitting organic compound,
• wherein the first light emitting element and the second light emitting element are connected in series,
• wherein the first light emitting layer and the second light emitting layer are overlapped with each other, and
• wherein the second light emitting layer comprises a fifth light emitting layer and a sixth light emitting layer which shows a different emission color from an emission color of the fifth light emitting layer.