μ-LED, μ-LED device, display and method for the same
The invention relates to various aspects of a μ-LED or a μ-LED array for augmented reality or lighting applications, in particular in the automotive field. The μ-LED is characterized by particularly small dimensions in the range of a few μm.
1. A μ-LED arrangement for generating a pixel of a display, comprising:
a carrier substrate;
at least three μ-LEDs, which are arranged on an assembly side of the carrier substrate;
wherein the at least three μ-LEDs are adapted to emit light of different colors transverse to a carrier substrate plane in a direction away from the carrier substrate;
a reflector element;
wherein the reflector element is spatially arranged on the assembly side of the carrier substrate;
wherein the reflector element is covering and laterally surrounding the at least three μ-LEDs and is configured to reflect the light emitted by the at least three μ-LEDs in a second direction of the carrier substrate;
wherein the carrier substrate is at least partially transparent so that the light reflected from the reflector element propagates through the carrier substrate and emerges at a display side of the carrier substrate opposite the assembly side; and
wherein the at least three μ-LEDs have a common electrical contact on a side of the at least three μ-LEDs facing the reflector element.
2. The μ-LED arrangement according to claim 1 , wherein a diffuser layer is provided and/or a reflector material has diffuser particles for scattering the light reflected by the at least three μ-LEDs on a side of the reflector element directed towards the at least three μ-LEDs.
3. The μ-LED arrangement according to claim 1 , wherein the reflector element forms an electrical contact of the at least three μ-LEDs.
4. The μ-LED arrangement according to claim 1 , wherein the reflector element is configured and shaped such that at least 90% of the light emitted by the at least three μ-LEDs is incident on the assembly side of the carrier substrate at an angle between 45 and 90 degrees relative to the carrier substrate plane.
5. The μ-LED arrangement according to claim 1 , wherein a passivation layer is additionally provided for attenuating or eliminating reflections of the light at mesa edges of the at least three μ-LEDs.
6. The μ-LED arrangement according to claim 1 , wherein a light absorbing coating is provided on the assembly side and/or the display side of the carrier substrate outside the reflector element.
7. The μ-LED arrangement according to claim 1 ,
wherein a color filter element is arranged on the display side of the carrier substrate opposite the reflector element; and
wherein the color filter element allows a primary color spectrum of the at least three μ-LEDs to pass and attenuates deviating color spectra.
8. The μ-LED arrangement according to claim 1 , in which a light-shaping structure, in particular a photonic structure is incorporated in or on the carrier substrate, which first and second regions with different refractive indexes are incorporated.
9. The μ-LED arrangement according to claim 1 , in which a light-shaping and/or a light-converting structure having a first area and a second area is arranged on the display side of the carrier substrate.
10. The μ-LED arrangement according to claim 1 , comprising a converter material surrounding at least one μ-LED of the at least three μ-LEDs and filling a space between the at least one μ-LED and a reflector material.
11. The μ-LED arrangement according to claim 2 , wherein the diffuser layer and/or the diffuser particles comprise Al 2 O 2 and/or TiO 2 .
12. The μ-LED arrangement according to claim 1 , wherein the reflector element surrounds the at least three μ-LEDs in a circular, polygonal or parabolic shape.
13. The μ-LED arrangement according to claim 1 , wherein the carrier substrate comprises polyamide, a transparent plastic, resin or glass.
14. The μ-LED arrangement according to claim 1 , wherein the reflector element is formed as a reflective layer of the at least three μ-LEDs.
15. The μ-LED arrangement according to claim 1 , wherein the display side of the carrier substrate has an uneven and/or roughened structure.
16. The μ-LED arrangement according to claim 9 , wherein the first area and the second area comprise a converted material.
17. The μ-LED arrangement according to claim 1 , further comprising a converter material on the display side of the carrier substrate.