Light intensity adaptive LED sidewalls

Patent metadata

Field	Value
Publication number	US-11557703-B2
Application number	US-201816226487-A
Country	US
Kind code	B2
Filing date	Dec 19, 2018
Priority date	Dec 21, 2017
Publication date	Jan 17, 2023
Grant date	Jan 17, 2023

Abstract

A first pixel with a first pixel sidewall is disclosed. A second pixel with a second pixel sidewall facing the first pixel sidewall is also disclosed. A first dynamic optical isolation material between the first pixel sidewall and the second pixel sidewall and configured to change an optical state based on a state trigger such that a light behavior at the first pixel sidewall for a light emitted by one of the first pixel and the second pixel is determined by the optical state, is also disclosed.

First claim

The invention claimed is:

1. A pixel array device comprising:
an array of pixels, each pixel separated from an adjacent pixel in the array by a lane, each pixel having sidewalls and comprising a n-type region, an active region, and a p-type region; and
a dynamic optical isolation material attached to a sidewall of a first pixel in the array, the sidewall located in the lane between the first pixel and another pixel in the array, the dynamic optical isolation material switchable between a plurality of optical states comprising a first optical state configured to hinder a transmission of light through the dynamic optical isolation material and a second optical state configured to allow light to pass through the dynamic optical isolation material, the dynamic optical isolation material configured to switch between optical states based on a state trigger,
the lane between the first pixel and the another pixel in the array configured so that when the dynamic optical isolation material in the lane is in the second optical state, the lane is transparent.

2. The device of claim 1 , wherein the first optical state prevents light from passing through the dynamic optical isolation material.

3. The device of claim 1 , wherein the first optical state scatters light that passes through the dynamic optical isolation material.

4. The device of claim 1 , wherein the dynamic optical isolation material is one of a thermochromic material, a thermotropic material, electrochromic and a photochromic material.

5. The device of claim 4 comprising a second dynamic optical isolation material attached to the dynamic optical isolation material, wherein the second dynamic optical isolation material is one of a thermochromic material, a thermotropic material, electrochromic and a photochromic material.

6. The device of claim 1 , wherein the state trigger is one of an optical addressing, an electrical addressing, or a temperature change.

7. The device of claim 1 , wherein the state trigger is provided by a pixel in the array.

8. The device of claim 1 , wherein the state trigger is provided by the combination two or more pixels in the array.

9. The device of claim 1 , wherein the first pixel comprises wavelength converting layer and the dynamic optical isolation material is attached to a sidewall of wavelength converting layer.

10. The device of claim 1 , comprising a second dynamic optical isolation material attached to a non-sidewall surface of the first pixel.

11. The device of claim 1 , wherein the first optical state is one of an opaque state, a scattering state and a reflective state and the second optical state that is one of a transparent state and a non-scattering state.

12. The device of claim 1 , wherein the array of pixels is segmented into groups of pixels such that each group may be individually addressable.

13. A method comprising:
addressing the first pixel in the pixel array device of claim 1 causing the active region of the first pixel to emit light; and
sending a state trigger to the dynamic optical isolation material attached to a sidewall of a first pixel causing the dynamic optical isolation material to switch optical states.

14. A method comprising:
addressing a first group of pixels in the pixel array device of claim 12 causing the active regions of the pixels in the first group to emit light;
not addressing a second group of pixels in the pixel array device of claim 12 , the second group of pixels different from the first group of pixels; and
sending a state trigger to the dynamic optical isolation material attached to pixel sidewalls between adjacent pixels in the first group of pixels causing the dynamic optical isolation material to switch optical states.

15. A pixel array device comprising:
an array of pixels, each pixel separated from an adjacent pixel in the array by a lane, each pixel having sidewalls and comprising a n-type region, an active region, and a p-type region, the array of pixels is segmented into groups of pixels such that each group may be individually addressable; and
a thermochromic material attached to sidewalls of the pixels in the array, the sidewalls located in the lanes between adjacent pixels in the array, the thermochromic material switchable between a transparent and non-transparent state as a result of temperature changes in the thermochromic material,
the lanes configured so that when the thermochromic material in the lanes is in the transparent state, the lanes are transparent.

16. The device of claim 15 wherein the transparent state is at least 95% transparent.

17. A method comprising:
addressing a first group of pixels in the device of claim 15 causing the active regions of the pixels in the first group to emit light and causing the thermochromic material attached to sidewalls of the pixels in the first group to switch to a transparent state; and
not addressing a second group of pixels in the device of claim 15 , the thermochromic material attached to sidewalls of the pixels in the second group remain in a non-transparent state, the second group of pixels different from the first group of pixels.

18. A pixel array device comprising:
an array of pixels, each pixel separated from an adjacent pixel in the array by a lane, each pixel having sidewalls and comprising a n-type region, an active region, and a p-type region, the array of pixels is segmented into groups of pixels such that each group may be individually addressable; and
a photochromic material attached to sidewalls of the pixels in the array, the sidewalls located in the lanes between adjacent pixels in the array, the photochromic material switchable between a transparent and non-transparent state,
the lanes configured so that when the photochromic material in the lanes is in the transparent state, the lanes are transparent.

19. The device of claim 18 wherein the transparent state is at least 95% transparent.

20. A method comprising:
addressing a first group of pixels in the device of claim 18 causing the active regions of the pixels in the first group to emit light;
illuminating the photochromic material attached to sidewalls of the pixels in the first group causing the photochromic material to switch to a transparent state; and
not addressing a second group of pixels in the device of claim 18 , the photochromic material attached to sidewalls of the pixels in the second group remain in a non-transparent state, the second group of pixels different from the first group of pixels.

Assignees

• Lumileds Llc

Inventors

• Shimizu Kentaro
• Bohmer Marcel Rene
• Estrada Daniel
• Heuts Jacobus Johannes Franciscus Gerardus

Classifications

• F21S41/645

  by electro-optic means, e.g. liquid crystal or electrochromic devices · CPC title

• G02F2203/01

  transmissive · CPC title

• G02F1/163

  Operation of electrochromic cells, e.g. electrodeposition cells; Circuit arrangements therefor · CPC title

• G02F2203/02

  reflective · CPC title

• F21S41/64

  by changing their light transmissivity, e.g. by liquid crystal or electrochromic devices · CPC title