LIGHT EMITTING UNIT AND DISPLAY DEVICE INCLUDING THE SAME

• US 20120256163A1
• Filed: 04/10/2012
• Published: 10/11/2012
• Est. Priority Date: 04/11/2011
• Status: Abandoned Application

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Park, Chan-Jae, YOON, Sanghyuck
• Application Number:
  US13/443,732
• Publication Number:
  US 20120256163A1
• Time in Patent Office: Days
• US Class Current: 257/13
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133614 using photoluminescence, e.g. phosphors illuminated by UV or blue light
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials

Abstract

A display device including a display panel and a light emitting unit providing light to the display panel is described herein. The light emitting unit includes a light emitting diode and a light emitting layer. The light emitting diode emits a first light. The light emitting layer includes quantum dots and fluorescent particles. The quantum dots are disposed on the light emitting diode and absorb the first light to emit a second light of a wavelength different from that of the first light. The fluorescent particles absorb the first light to emit a third light of a wave length different from those of the first and second light.

Claims

1. A display device comprising:

a display panel displaying an image; and

a light emitting unit providing white light to the display panel,

wherein the light emitting unit includes;

at least one light source emitting a first light; and

a light emitting layer comprising;

a plurality of quantum dots disposed on the light source and absorbing the first light to emit a second light, the second light having a wavelength different from a wavelength of the first light; and

a plurality of fluorescent particles absorbing the first light to emit a third light, the third light having a wavelength different from the wavelengths of the first and second light.

14. The display device of claim 1, wherein the display panel is a liquid crystal display panel, an electrophoretic display panel, an electrowetting display panel, or a microelectromechanical system (MEMS) display panel.

2. The display device of claim 2, wherein the first light is a blue light, the second light is one of a red light and a green light, and the third light is the other of the red light and the green light.

3. The display device of claim 2, wherein the quantum dots comprise at least one of ZnSe, CdSe, and InGaP.

4. The display device of claim 3, wherein the first light has a peak wavelength ranging from about 380 nm to about 470 nm.

5. The display device of claim 2, wherein the second light is green light, and the third light is red light.

6. The display device of claim 5, wherein the fluorescent particles comprise nitride-based fluorescent particles.

7. The display device of claim 6, wherein the nitride-based fluorescent particles comprise at least one of CaAlSiN₃:

Eu and SrAlSiN₃;

Eu.

8. The display device of claim 7, wherein the second light has a peak wavelength ranging from about 500 nm to about 560 nm, and the third light has a peak wavelength ranging from about 580 nm to about 650 nm.

9. The display device of claim 6, wherein the display panel comprises:

a first substrate;

a second substrate opposed to the first substrate;

an image display layer disposed between the first and second substrates; and

a color filter layer disposed between the first substrate and the image display layer or between the second substrate and the image display layer to express a color.

10. The display device of claim 9, wherein the color filter layer comprises:

a first color filter for transmitting light of a first wavelength band;

a second color filter for transmitting light of a second wavelength band different from the first wavelength band; and

a third color filter for transmitting light of a third wavelength band different from the first and second wavelength bands,

wherein the second wavelength band ranges from about 450 nm to about 655 nm.

11. The display device of claim 10, wherein the first wavelength band ranges from about 380 nm to about 550 nm.

12. The display device of claim 10, wherein the third wavelength band ranges from about 540 nm to about 780 nm.

13. The display device of claim 10, wherein the first substrate comprises a plurality of pixels, and each of the pixels corresponds to one of the first, second, and third filters.

15. A light emitting unit comprising:

a light emitting diode for emitting a first light; and

a light emitting layer,

wherein the light emitting layer includes;

a plurality of quantum dots disposed on the light emitting diode and absorbing the first light to emit a second light, the second light having a wavelength different from a wavelength of the first light; and

a plurality of fluorescent particles absorbing the first light to emit third light, the third light having a wavelength different from the wavelengths of the first and second light.

16. The light emitting unit of claim 15, wherein the first light is a blue light, the second light is one of a red light and a green light, and the third light is the other of the red light and the green light.

17. The light emitting unit of claim 16, wherein the second light is green light, and the third light is red light.

18. The light emitting unit of claim 17, wherein the fluorescent particles comprise nitride-based fluorescent particles.

19. The light emitting unit of claim 18, wherein the fluorescent particles comprise at least one of CaAlSiN₃:

Eu and SrAlSiN₃;

Eu.

20. The light emitting unit of claim 15, wherein the quantum dots comprise at least one of ZnSe, CdSe, and InGaP.