Smart-home device light rings with lens spacing for uniform output

Patent metadata

Field	Value
Publication number	US-10914430-B2
Application number	US-201815940427-A
Country	US
Kind code	B2
Filing date	Mar 29, 2018
Priority date	Dec 31, 2017
Publication date	Feb 9, 2021
Grant date	Feb 9, 2021

Abstract

A light ring assembly for a smart-home device may include a plurality of light-emitting diodes (LEDs) and a light guide, where the light guide may include a plurality of cutouts that receive the plurality of LEDs, and a plurality of transmissive sections between the plurality of cutouts. The light ring assembly may also include an output surface that receives light emitted from the plurality of LEDs through the plurality of transmissive sections, where the output surface is substantially circular. The light guide may also include a plurality of micro-lenses in the plurality of transmissive sections where a relative density of the micro-lenses increases as the transmissive sections extend away from the plurality of cutouts.

First claim

What is claimed is:

1. A method of generating a uniform light ring in a smart-home device, the method comprising:
generating light from a plurality of light-emitting diodes (LEDs);
receiving the light from the plurality of LEDs at a light guide, wherein the light guide comprises:
a plurality of cutouts that receive the plurality of LEDs;
a plurality of transmissive sections between the plurality of cutouts that are arranged in a ring shape to form the light guide, wherein the plurality of cutouts comprises surfaces that absorbs light emitted from a corresponding previous LED in the plurality of LEDs to optically separate light traveling between sequential transmissive sections in the plurality of transmissive sections; and
a plurality of micro-lenses in the plurality of transmissive sections, wherein a linear number density of the micro-lenses across a thickness of the transmissive sections increases as the transmissive sections extend away from the plurality of cutouts, and wherein the thickness of the transmissive sections is orthogonal to a direction in which the transmissive sections extend away from the plurality of cutouts;

channeling light down the plurality of transmissive sections; and
emitting light from an output surface of the light guide, wherein the output surface is substantially circular.

2. The method of claim 1 , wherein the plurality of LEDs are top-firing LEDs.

3. The method of claim 2 , wherein the plurality of transmissive sections run parallel to the light emitted from the top-firing LEDs.

4. The method of claim 3 , wherein the plurality of transmissive sections have a scalloped shape.

5. The method of claim 1 , wherein the plurality of LEDs are side-firing LEDs.

6. The method of claim 5 , the plurality of transmissive sections run between each of the plurality of cutouts in a substantially circular shape.

7. The method of claim 1 , wherein the smart-home device further comprises a diffusive ring through which light from the output surface is diffused before leaving the smart-home device.

8. The method of claim 1 , wherein the smart-home device comprises a video camera.

9. The method of claim 1 , wherein the smart-home device comprises a motion sensor of a security system.

10. The method of claim 1 , wherein a thickness of the transmissive sections tapers as the transmissive sections extend away from the plurality of cutouts.

11. A light ring assembly for a smart-home device, the light ring assembly comprising:
a plurality of light-emitting diodes (LEDs);
a light guide, wherein the light guide comprises:
a plurality of cutouts that receive the plurality of LEDs;
a plurality of transmissive sections between the plurality of cutouts that are arranged in a ring shape to form the light guide, wherein the plurality of cutouts comprises surfaces that absorbs light emitted from a corresponding previous LED in the plurality of LEDs to optically separate light traveling between sequential transmissive sections in the plurality of transmissive sections; and
a plurality of micro-lenses in the plurality of transmissive sections, wherein a linear number density of the micro-lenses across a thickness of the transmissive sections increases as the transmissive sections extend away from the plurality of cutouts, and wherein the thickness of the transmissive sections is orthogonal to a direction in which the transmissive sections extend away from the plurality of cutouts; and

an output surface that receives light emitted from the plurality of LEDs through the plurality of transmissive sections, wherein the output surface is substantially circular.

12. The light ring assembly of claim 11 , further comprising a light mask that is coupled to the light guide.

13. The light ring assembly of claim 12 , wherein the light mask comprises a Mylar tape that is adhered to the exterior surface of the light guide.

14. The light ring assembly of claim 12 , wherein the light mask is coupled to a portion of the light guide that is at least in part directly above one of the plurality of cutouts.

15. The light ring assembly of claim 12 , wherein a width of the light mask tapers as the light mask extends away from one of the plurality of cutouts.

16. The light ring assembly of claim 11 , wherein the smart-home device comprises a first reflective surface, wherein light emitted from the output surface of the light ring assembly is reflected off of the first reflective surface before exiting the smart-home device.

17. The light ring assembly of claim 16 , wherein the smart-home device comprises a second reflective surface, wherein light reflected off of the first reflective surface is reflected off of the second reflective surface before exiting the smart-home device.

18. The light ring assembly of claim 11 , wherein a light output of the output surface is substantially uniform.

19. The light ring assembly of claim 11 , wherein the plurality of LEDs consists of two LEDs.

20. The light ring assembly of claim 11 , wherein the plurality of cutouts are evenly distributed in a circular pattern around the light guide.

Assignees

• Google Llc

Inventors

• Kraz Mark
• Volmering Amber
• Macomber Bryan
• Grillo Jacobi
• Kilgore Adam

Classifications

• H04N23/56

  provided with illuminating means · CPC title

• F21V14/06

  by movement of refractors {(in vehicle head lamps F21S41/635)} · CPC title

• F21V13/12

  Combinations of only three kinds of elements · CPC title

• F21V3/0625

  the material diffusing light, e.g. translucent plastics · CPC title

• F21Y2103/33

  annular · CPC title