Light emitting diode device incorporating a white light emitting layer in combination with a plurality of optical microcavities

1. A light-emitting diode device, comprising:

a) a substrate;

b) a reflective electrode and a semi-transparent electrode formed over the substrate and an unpatterned white light-emitting layer formed between the reflective electrode and the semi-transparent electrode, the reflective electrode, semi-transparent electrode, and unpatterned white-light-emitting layer forming an optical microcavity, and wherein either the reflective or semi-transparent electrode is patterned to form a plurality of independently controllable light-emitting elements;

c) a plurality of color filters formed over a side of the semi-transparent electrodes opposite the unpatterned white light-emitting-layer in correspondence with the light-emitting elements, the plurality of color filters having at least two different colors and wherein at least one light-emitting element has no color filter; and

d) wherein the light-emitting element having no color filter includes a plurality of optical microcavities tuned to one or more peak wavelengths approximately corresponding to the peak emission wavelengths of the white light-emitting layer, each optical microcavity tuned to emit light at a different wavelength.

2. The device of claim 1 wherein the optical microcavities of the light-emitting elements having color filters are tuned to a peak wavelength approximately corresponding to the peak transmission wavelength of the color filter of the light-emitting element.

3. The light-emitting diode device of claim 1 wherein the optical microcavities of the at least one light-emitting element that has no color filter are tuned to emit colors that, in combination, are perceived as white.

4. The light-emitting diode device of claim 1 wherein the optical microcavities of the at least one light-emitting element that has no color filter are tuned to emit red, green, and blue light, or yellow and blue light, or red and cyan light.

5. The light-emitting diode device of claim 1 , wherein the white light-emitting layer comprises organic materials.

6. The light-emitting diode device of claim 1 wherein the white light-emitting layer emits light having a spectrum with two or more peaks.

7. A light-emitting diode device, comprising:

a) a substrate;

b) a reflective electrode and a semi-transparent electrode formed over the substrate and an unpatterned white light-emitting layer formed between the reflective electrode and the semi-transparent electrode, the reflective electrode, semi-transparent electrode, and unpatterned white-light-emitting layer forming an optical microcavity, and wherein either the reflective or semi-transparent electrode is patterned to form a plurality of independently controllable light-emitting elements;

c) a plurality of color filters formed over a side of the semi-transparent electrodes opposite the unpatterned white light-emitting-layer in correspondence with the light-emitting elements, the plurality of color filters having at least two different colors and wherein at least one light-emitting element has no color filter;

d) wherein the light-emitting element having no color filter includes a plurality of optical microcavities tuned to emit complementary colors of light, each optical microcavity tuned to emit light at a different wavelength.

8. A light-emitting diode device, comprising:

a) a substrate;

b) a reflective electrode and a semi-transparent electrode formed over the substrate and an unpatterned white light-emitting layer formed between the reflective electrode and the semi-transparent electrode, the reflective electrode, semi-transparent electrode, and unpatterned white-light-emitting layer forming an optical microcavity, and wherein either the reflective or semi-transparent electrode is patterned to form a plurality of independently controllable light-emitting elements;

c) a plurality of color filters formed over a side of the semi-transparent electrodes opposite the unpatterned white light-emitting-layer in correspondence with the light-emitting elements, the plurality of color filters having at least two different colors and wherein at least one light-emitting element has no color filter;

d) wherein the light-emitting element having no color filter includes a plurality of optical microcavities, each optical microcavity tuned to emit light at a different wavelength; and

e) wherein the white light-emitting layer comprises inorganic quantum dots formed in a poly-crystalline semiconductor matrix.

9. A method of making an LED device, comprising the steps of:

a) providing a substrate;

b) forming a reflective electrode and a semi-transparent electrode over the substrate and forming an unpatterned white light-emitting layer between the reflective electrode and the semi-transparent electrode, the reflective electrode, semi-transparent electrode, and unpatterned white-light-emitting layer forming an optical microcavity, and wherein either the reflective or semi-transparent electrode is patterned to form a plurality of independently controllable light-emitting elements;

c) forming a plurality of color filters over a side of the semi-transparent electrodes opposite the unpatterned white light-emitting-layer in correspondence with the light-emitting elements, the plurality of color filters having at least two different colors and wherein at least one light-emitting element has no color filter; and

d) wherein the optical microcavity of one or more of the light-emitting elements that have no color filter comprises a plurality of optical microcavities tuned to one or more peak wavelengths approximately corresponding to the peak emission wavelengths of the white-light-emitting layer, each optical microcavity tuned to emit light at a different wavelength.