Lighting arrangement

Patent metadata

Field	Value
Publication number	US-9714754-B2
Application number	US-201314396219-A
Country	US
Kind code	B2
Filing date	Apr 23, 2013
Priority date	Apr 26, 2012
Publication date	Jul 25, 2017
Grant date	Jul 25, 2017

Abstract

Lighting arrangement ( 1, 1 ′) comprising a light source ( 2 ) for generating light; a spreading element ( 3 ) realized to laterally spread the generated light in a spreading plane (S), defined by an optical axis (A O ) of the light source ( 2 ) and a longitudinal axis (L) of the spreading element ( 3 ), to give an essentially uniform quantity of light per unit area at an emission face ( 41, 51 ) orthogonal to the spreading plane (S) and parallel to the longitudinal axis (L) of the spreading element ( 3 ) and a light redirecting element ( 4, 5 ) arranged to collect the spread light, which comprises a longitudinal planar emission face ( 41, 51 ), and is realized to collect the laterally spread light and to emit the collected light essentially uniformly from the emission face ( 41, 51 ).

First claim

The invention claimed is:

1. A lighting arrangement, comprising:
a light source for generating light;
a spreading element configured to laterally spread the generated light in a spreading plane, defined by an optical axis of the light source and a longitudinal axis of the spreading element, to give a uniform quantity of light per unit area at a plane orthogonal to the spreading plane and parallel to the longitudinal axis of the spreading element; and
a light redirecting element provided with a collecting surface to collect the laterally spread light and an emission face to emit the collected light,
wherein the light redirecting element comprises a single Fresnel lens associated with the light source and is configured to emit the collected light uniformly from the emission face,
the emission face is longitudinal planar and comprises a long rectangular emission face, and
the collecting surface comprises a central refractive zone arranged to coincide with the optical axis of the light source and a plurality of distinct lateral refracting zones at sides of the central refractive zone for collecting the laterally spread light, wherein each of the distinct lateral refracting zones comprises a respective collecting face arranged to collect a light portion from said spreading element having a certain incidence angle range and a respective refracting body for refracting the light portion through the emission face, wherein the surface areas of at least a first subset of the collecting faces progressively increase as a distance of the collecting faces of the first subset from said light source increases along a direction and wherein the surface areas of at least a second subset of the collecting faces progressively decrease as a distance of the collecting faces of the second subset from said light source increases along said direction, wherein said second subset is disposed farther from said light source than said first subset along said direction and wherein the rate of the progressive increase is symmetrical with the rate of the progressive decrease and wherein each of the first subset of the collecting faces and the second subset of the collecting faces extend to a point and each point is positioned a same distance from the emission face.

2. The lighting arrangement according to claim 1 , wherein the light source comprises a single light-emitting diode chip.

3. The lighting arrangement according to claim 1 , wherein a length of the emission face exceeds a width of the emission face by a factor of at least 3.

4. A lighting element, for use in the lighting arrangement according to claim 1 , comprising:
the light source for generating light; and
the spreading element, wherein the spreading element is configured to laterally spread the generated light in the spreading plane, defined by the optical axis of the light source and the longitudinal axis of the spreading element, to give a uniform quantity of light per unit area at the plane orthogonal to the spreading plane and parallel to the longitudinal axis of the spreading element.

5. The lighting element according to claim 4 , wherein the spreading element comprises two distinct lobes arranged along the longitudinal axis of the spreading element, whereby the spreading element is arranged to accommodate the light source symmetrically between the two lobes.

6. The lighting element according to claim 4 , comprising a receptacle for containing the light source, which receptacle comprises a reflective surface, and wherein the receptacle and the spreading element are configured to obtain a light output distribution comprising a first lateral spread portion in a first half of the spreading plane to one side of the optical axis, and a second lateral spread portion in the other half of the spreading plane, wherein a lateral spread portion of the light output distribution is bounded by a first angle subtended from the optical axis and a second angle subtended from the optical axis.

7. The lighting element according to claim 6 , wherein the first angle comprises at least 35° subtended from the optical axis.

8. The lighting element according to claim 6 , wherein the second angle comprises an angle exceeding the first angle by at most 25°.

9. A light redirecting element, comprising:
a collecting surface to collect light from a light source having an optical axis, and an emission face to emit the collected light,
wherein the light redirecting element comprises a single Fresnel lens associated with the light source and is configured to emit the collected light uniformly from the emission face,
wherein the emission face is longitudinal planar and comprises a long rectangular emission face, and
wherein the collecting surface comprises a central refractive zone arranged to coincide with the optical axis of the light source and a plurality of distinct lateral refracting zones at sides of the central refractive zone for collecting the light,
wherein each of the distinct lateral refracting zones comprises a respective collecting face arranged to collect a light portion having a certain incidence angle range and a respective refracting body for refracting the light portion through the emission face,
wherein the surface areas of at least a first subset of the collecting faces progressively increase as a distance of the collecting faces of the first subset from said light source increases along a direction and wherein the surface areas of at least a second subset of the collecting faces progressively decrease as a distance of the collecting faces of the second subset from said light source increases along said direction, and wherein each of the first subset of the collecting faces and the second subset of the collecting faces extend to a point and each point is positioned a same distance from the emission face,
wherein said second subset is disposed farther from said light source than said first subset along said direction and wherein the rate of the progressive increase is symmetrical with the rate of the progressive decrease.

10. The light redirecting element according to claim 9 , wherein the light redirecting element is configured to refract the collected light into an emission plane, wherein the emission plane comprises a continuation of the spreading plane.

11. A display illumination arrangement, comprising:
a display plate with a number of in-coupling faces arranged around a perimeter of the display plate; and
a number of lighting arrangements according to claim 1 , arranged such that the emission face of a lighting arrangement is directed at an in-coupling face of the display plate.

Assignees

• Philips Lighting Holding Bv

Inventors

• Spinger Benno
• Martin Paul Scott
• Bloemen Pascal Jean Henri
• Tai Kuochou

Classifications

• G02B6/003

  Lens or lenticular sheet or layer · CPC title

• F21S43/243

  emitting light from one or more of its extremities · CPC title

• F21S43/249

  with two or more light sources being coupled into the light guide · CPC title

• F21S43/239

  plate-shaped · CPC title

• G02B6/0028

  Light guide, e.g. taper · CPC title