OLED devices having improved efficiency

• US 10,686,159 B2
• Filed: 06/03/2016
• Issued: 06/16/2020
• Est. Priority Date: 06/26/2015
• Status: Active Grant

• Current Assignee: Universal Display Corporation
• Original Assignee: Universal Display Corporation
• Inventors: Ma, Ruiqing, Brown, Julia J., Xiang, Chaoyu, Hack, Michael, Paynter, Jason
• Primary Examiner(s): Zhu, Sheng-Bai
• Application Number:
  US15/173,109
• Publication Number:
  US 20160380238A1
• Time in Patent Office: 1,474 Days
• Field of Search: 257 91, 345522, 313504
• CPC Class Codes: H10K 2102/351 Thickness
• CPC Class Codes: H10K 50/854 comprising scattering means
• CPC Class Codes: H10K 50/858 comprising refractive means, e.g. lenses
• CPC Class Codes: H10K 59/35 comprising red-green-blue [RGB] subpixels
• CPC Class Codes: H10K 59/38 comprising colour filters or colour changing media [CCM]

Abstract

Devices, components and fabrication methods are provided for improving the efficiency of OLED displays. An outcoupling component such as a microlens array (MLA) is attached to an OLED, with a relatively small distance between the MLA and the OLED. Cross-talk and back scattering are reduced by the use of colored lenses, focusing layers, and other methods.

Claims

1. An organic light emitting display comprising:

a first emissive region having a width across a substrate of 2r; and

an outcoupling component disposed over the emissive region and having a horizontal base surface, the base surface disposed a vertical distance t from the first emissive region and optically coupled to the first emissive region, the outcoupling component having an index of refraction n_lens and a width across the base surface of 2R;

wherein [0≤

t<

√

{square root over (n_lens²−

1)}*(r+R)].

2. An organic light emitting display as recited in claim 1, wherein d≥

(n_lens−

1)r, where d is the distance from a side edge of the first emissive region to a projection of an edge of the outcoupling component onto the substrate.

3. An organic light emitting display as recited in claim 1, further comprising a spacing layer disposed between the first emissive region and the outcoupling component, wherein the spacing layer comprises a material having an index of refraction within 0.02 of n_lens.

4. An organic light emitting display as recited in claim 1, wherein t is not greater than 80 μ

m, not greater than 27 μ

m, or not greater than 15 μ

m.

5. An organic light emitting display as recited in claim 1, wherein the outcoupling component comprises a outcoupling component array having a total width 2R, wherein each outcoupling component in the outcoupling component array is disposed at least partially over the emissive region, and wherein d is a distance from an edge of the emissive region to a projection of an edge of an outermost outcoupling component of the outcoupling component array.

6. An organic light emitting display as recited in claim 1, further comprising a light absorption material disposed on an edge of the outcoupling component disposed closest to the emissive region.

7. An organic light emitting display as recited in claim 1, further comprising a defocusing layer disposed between the outcoupling component and the emissive region, wherein the defocusing layer has an index of refraction n_def that is less than n_lens.

8. An organic light emitting display as recited in claim 7, wherein

9. An organic light emitting display as recited in claim 1, wherein the outcoupling component comprises a color agent.

10. An organic light emitting display as recited in claim 9, wherein the color of the color agent is the same as a color of a peak wavelength of light emitted by the emissive region.

11. An organic light emitting display as recited in claim 1, further comprising a circular polarizer disposed between the outcoupling component and the emissive region.

12. An organic light emitting display as recited in claim 1, wherein the display comprises a plurality of pixels, each pixel comprising a plurality of subpixels, and wherein the emissive region emits light to be emitted by one of the plurality of subpixels.

13. An organic light emitting display as recited in claim 12, wherein the display comprises at least one outcoupling component for each of the plurality of subpixels.

14. An organic light emitting display as recited in claim 12, wherein the display comprises subpixels of a plurality of colors, and the display comprises outcoupling components for subpixels of only one color of the plurality of colors.

15. An organic light emitting display as recited in claim 12, wherein each emissive region is individually addressable.

16. An organic light emitting display as recited in claim 1, wherein the maximum thickness of the outcoupling component is at least 10% greater than r.

17. An organic light emitting display as recited in claim 1, wherein the outcoupling component has a decreasing cross-sectional area along a line normal to the emissive region and in a direction moving away from the emissive region.

18. An organic light emitting device as recited in claim 17, wherein the outcoupling component comprises at least one flat-topped microlens.

19. An organic light emitting display comprising:

a first emissive region having a width across a substrate of 2r; and

a scattering layer disposed over the emissive region and having a width of 2R; and

a spacing layer with a thickness oft and an average refractive index of n_sp, the spacing layer being disposed between and optically coupled to the first emissive region and the scattering layer;

wherein 0<

t<

√

{square root over (n_sp²−

1)}*(r+R).