Recessed wall wash light fixture with glare control

Patent metadata

Field	Value
Publication number	US-9671076-B2
Application number	US-201514702157-A
Country	US
Kind code	B2
Filing date	May 1, 2015
Priority date	May 1, 2015
Publication date	Jun 6, 2017
Grant date	Jun 6, 2017

Abstract

A recessed wall wash light fixture includes a light source and a hollow light guide. The hollow light guide has a reflective internal surface and forms upper and lower apertures along its upper and lower boundaries; the lower aperture is slanted upwardly in the forward direction. The hollow light guide includes a forward section and a rear section having respective wall surfaces. The forward and rear wall surfaces substantially meet one another at midlines that extend downwardly from the upper aperture to the lower aperture.

First claim

What is claimed is:

1. A recessed wall wash light fixture that emits light downwardly and preferentially toward a forward direction into a space beneath a ceiling, the light fixture comprising:
a light source that emits the light;
a hollow light guide that reflects at least a portion of the light, wherein the hollow light guide substantially encloses a space between:
an upper aperture, wherein the light source is configured and oriented so as to emit the light through the upper aperture, and
a lower aperture that is slanted upwardly in the forward direction so as to have an upper, forward side and a lower, rearward side;

the hollow light guide consisting essentially of:
a first reflective sheet that is curved to form a forward section having:
a forward wall centerline that extends downwardly from a forward side of the upper aperture to the upper, forward side of the lower aperture, and
forward wall surfaces that extend laterally from both sides of the forward wall centerline, and curve rearwardly; and

a second reflective sheet that is curved to form a rear section having:
a rear wall centerline that is concave with respect to the forward wall centerline, and curves downwardly from a rearward side of the upper aperture to the lower, rearward side of the lower aperture, and
rear wall surfaces that extend laterally from both sides of the rear wall centerline, and curve forwardly;

such that the forward and rear wall surfaces substantially meet one another at midlines that extend downwardly from the upper aperture to the lower aperture.

2. The recessed wall wash light fixture of claim 1 , further comprising a diffuser disposed across the lower aperture such that substantially all of the light passes through the diffuser.

3. The recessed wall wash light fixture of claim 2 , wherein the diffuser has a field angle within the range of 10 to 50 degrees.

4. The recessed wall wash light fixture of claim 2 , further comprising a housing that includes a mounting flange that defines an output aperture for the light fixture, wherein:
the housing is configured to couple with the ceiling when an upper surface of the mounting flange abuts a lower surface of the ceiling;
the output aperture is an opening within a lowermost planar surface of the mounting flange;
the housing supports the diffuser, the hollow light guide and the light source such that, when the mounting flange couples with the ceiling:
the upper aperture of the hollow light guide defines a plane that is substantially parallel with the upper surface of the mounting flange; and
the lower aperture of the hollow light guide is disposed above the output aperture, and forms an angle of 10 to 50 degrees with respect to the upper surface of the mounting flange.

5. The recessed wall wash light fixture of claim 4 , the housing further comprising a glare shield extending downwardly from at least a portion of a periphery of the output aperture, wherein the glare shield is configured to block light passing through any part of the diffuser from a glare-free region of the space.

6. The recessed wall wash light fixture of claim 5 , wherein:
the glare shield extends vertically downward from the portion of the periphery of the output aperture;
the glare shield extends furthest downwardly from a rear side of the output aperture; and
in a plane passing from front to rear through a center of the hollow light guide, a lower bound of the glare-free region is defined at an angle of greater than 40 degrees from horizontal.

7. The recessed wall wash light fixture of claim 1 , wherein the light source comprises one or more light-emitting diodes (LEDs) disposed on a circuit board so as to emit the light downwardly through the upper aperture of the hollow light guide, the light source defining a light emitter axis that is perpendicular to the circuit board and passes through a centroid of the LEDs.

8. The recessed wall wash light fixture of claim 7 , wherein:
the forward wall centerline is a straight line from the forward side of the upper aperture to the upper, forward side of the lower aperture;
the forward section curves in an azimuthal direction relative to the light emitter axis; and
the rear section curves in both azimuthal and axial directions relative to the light emitter axis.

9. The recessed wall wash light fixture of claim 1 , wherein:
the forward section:
reflects a first portion of the light from the light source such that it passes rearwardly and directly through the lower aperture of the hollow light guide, and
reflects a second portion of the light from the light source and directs the second portion rearwardly toward the rear section of the hollow light guide;

and the rear section:
re-reflects the second portion of the light from the light source such that it passes forwardly through the lower aperture of the hollow light guide,
reflects a third portion of the light from the light source such that it passes forwardly through the lower aperture of the hollow light guide,
reflects a fourth portion of the light from the light source downwardly, and
re-reflects the fourth portion of the light such that it passes forwardly through the lower aperture of the hollow light guide.

10. The recessed wall wash light fixture of claim 1 , wherein the forward and rear sections are discrete physical sections that are joined to form the hollow light guide.

11. The recessed wall wash light fixture of claim 1 , wherein at least one of the forward section and the rear section is formed of an metal that is coated at least on an internally facing surface thereof with one or more reflection-enhancing films, such that a reflectance of the internally facing surface exceeds 94%.

12. The recessed wall wash light fixture of claim 11 , wherein at least one of the reflection-enhancing films comprises silver, and the reflectance of the internally facing surface exceeds 97%.

13. The recessed wall wash light fixture of claim 11 , wherein the rear section is formed of a planar sheet of the metal having the one or more reflection-enhancing films, wherein:
the planar sheet comprises tabs having sides that are separated by substantially triangular slots when the sheet is unbent, and
the sides of the tabs substantially meet when the sheet is bent to form the rear section.

14. The recessed wall wash light fixture of claim 7 , wherein the circuit board is disposed proximate to the upper aperture, and wherein the light enters through the upper aperture without passing through optics.

Assignees

• Abl Ip Holding Llc

Inventors

• Chen Jie
• Hughes Jeffrey Paige
• Marquardt Craig Eugene
• Onda Joseph J
• Juda Mike Ken

Classifications

• F21V7/04

  Optical design · CPC title

• F21V21/044

  with elastically deformable elements, e.g. spring tongues · CPC title

• F21S8/026 Primary

  intended to be recessed in a ceiling or like overhead structure, e.g. suspended ceiling · CPC title

• F21Y2115/10

  Light-emitting diodes [LED] · CPC title

• F21V7/24

  characterised by the material · CPC title