Optical element, a lighting system and a luminaire for providing a skylight appearance

Patent metadata

Field	Value
Publication number	US-9476567-B2
Application number	US-201214233541-A
Country	US
Kind code	B2
Filing date	Jul 19, 2012
Priority date	Jul 20, 2011
Publication date	Oct 25, 2016
Grant date	Oct 25, 2016

Abstract

An optical element, a lighting system and a luminaire is provided. The optical element comprises a plate 100 and a plurality of collimating means. The optical element is to be used in front of a light source comprising a light emitting surface 106 , and the optical element is configured to obtain a skylight appearance. The plate 100 is to be arranged parallel to the light emitting surface 106 . The plate 100 is opaque and comprises a plurality of holes 104 . The plate 100 further comprises a reflective surface 102 which is to be arranged parallel to the light emitting surface 106 . The reflective surface 102 is light reflective in a predetermined spectral range to obtain a blue light emission 100 . The plurality of collimating means collimate a part of the light received from the light source to obtain a collimated light beam 112 in a specific direction. Each one of the collimating means comprises one of the plurality of holes of the plate 104.

First claim

The invention claimed is:

1. An optical element for use in front of a light source comprising a light emitting surface, the optical element being configured to obtain a skylight appearance including a direct sunlight effect and a bluish light emission, said optical element comprising:
a plate configured to be arranged parallel to the light emitting surface, the plate being opaque and comprising a plurality of holes, the plate further comprising a reflective surface configured to be arranged parallel to the light emitting surface, the reflective surface being light reflective in a predetermined spectral range for obtaining a blue light emission, and
a plurality of collimating means for obtaining a collimated light beam in a specific direction by transmitting a part of the light received from the light source, wherein said part has a light emission angle substantially in the specific direction, each one of the collimating means comprising one of the plurality of holes of the plate, wherein said optical element is configured such that, when said plate and said reflective surface are arranged parallel to the light emitting surface, light emitted from a side of said plate outputting said collimated light beam appears to have a first color along said specific direction and appears more bluish than said first color along a direction that is different than said specific direction.

2. The optical element according to claim 1 , wherein said side is a first side facing the ambient and including the reflective surface for reflecting ambient light to obtain a blue ambient light reflection and wherein the plate further includes a second side for receiving light from the light source, the second side being opposite the first side.

3. The optical element according to claim 2 , wherein the holes are light transmitting channels through the plate to form the collimating means, and the holes extend from the second side towards the first side in the specific direction.

4. The optical element according to claim 3 , wherein said light emission angle is a first light emission angle and wherein the light transmitting channels have walls being surfaces of the plate and facing the interior of the light transmitting channels, at least a part of the walls of the light transmitting channels are reflective in the predetermined spectral range for obtaining a blue diffuse light emission at light emission angles that are larger than said first light emission angle.

5. The optical element according to claim 1 , wherein said plate is a first plate, wherein said plurality of holes are a plurality of first holes, wherein said reflective surface is a first reflective surface and wherein the optical element comprises a second plate arranged parallel to the first plate and being separated from the first plate by a gap, wherein
the second plate comprises a plurality of second holes,
wherein at least a subset of the first holes and at least a subset of the second holes form pairs of holes such that each hole of the at least a subset of the first holes forms a respective pair of said pairs with a respective nearest hole of the plurality of second holes, wherein each given pair of the pairs of holes includes a respective imaginary central axis formed through a central point of the holes of said given pair, and wherein the imaginary central axes of said pairs of holes are arranged in parallel and the pairs of holes are arranged to collimate said part of the light received from the light source to obtain a respective collimated light beam in a direction of the imaginary central axes of said pairs of holes, each pair of said pairs of holes forming one of the collimating means, and
wherein the second plate comprises a second reflective surface, the first reflective surface facing the second reflective surface.

6. A lighting system comprising:
the optical element according to claim 1 ; and
a light guide comprising a light output window and a light input window, the light input window being arranged to receive the light from the light source and the light output window facing the optical element and being arranged to emit the light received from the light source towards the optical element.

7. The lighting system according to claim 6 , comprising a reflector arranged at a side of the light guide opposite the light output window of the light guide, wherein
the light guide comprises light outcoupling structures, multiple holes of the plurality of holes forming a pairs such that each hole of the multiple holes forms a respective pair of said pairs with a respective nearest light outcoupling structure of the light outcoupling structures, wherein each given pair of said pairs includes a respective imaginary central axis formed through a central point of the hole of the given pair and a central point of the outcoupling structure of the given pair, wherein the imaginary central axes of the pairs being arranged in parallel for collimating said part of the light received from the light source to obtain a respective collimated light beam in a direction of the imaginary central axes of the pairs, and each pair of the pairs forming one of the collimating means, and
wherein the reflective surface of the plate faces the light output window of the light guide for obtaining the blue light emission at light emission angles outside the light emission angles of the respective collimated light beams.

8. The lighting system according to claim 6 , wherein said side is a first side, wherein the light guide is a first light guide and wherein the lighting system further comprises a second light guide arranged at said first side of the optical element, said first side being opposite another side of the optical element facing the first light guide, the second light guide including two parallel surfaces being arranged parallel to the plate of the optical element, wherein
the reflective surface of the plate faces the second light guide, and
the second light guide further comprises light outcoupling structures at subareas of at least one of the parallel surfaces of the second light guide, wherein the subareas are separate from subareas of the at least one of the parallel surfaces of the second light guide through which the collimated light beam is transmitted, and wherein the outcoupling structures are arranged to emit light towards the reflective surface of the plate.

9. A lighting system comprising;
the optical element according to claim 1 ; and
TLeds comprising a light transmitting tube arranged as a light exit window and comprising Light Emitting Diodes, the TLeds being arranged to emit light towards the optical element and being arranged in the virtual plane.

10. The lighting system according to claim 9 , further comprising a diffuser arranged in between the TLeds and the optical element.

11. A luminaire comprising the optical element according to claim 1 .

12. A lighting system for use in front of a light source comprising a light emitting surface, the system being configured to obtain a skylight appearance including at least one of a direct sunlight effect or a bluish light emission, said lighting system comprising:
an optical element including a plate configured to be arranged parallel to the light emitting surface, the plate being opaque and comprising a plurality of holes, the plate further comprising a reflective surface configured to be arranged parallel to the light emitting surface, the reflective surface being light reflective in a predetermined spectral range for obtaining a blue light emission, wherein said optical element further comprises a plurality of collimating means for obtaining a collimated light beam in a specific direction by tr

Assignees

• Seuntiens Petrus Johannes Hendrikus
• Salters Bart Andre
• Onac Gabriel-Eugen
• Meerbeek Berent Willem
• Van Loenen Evert Jan
• Koninklijke Philips Nv

Inventors

• Seuntiens Petrus Johannes Hendrikus
• Salters Bart Andre
• Onac Gabriel-Eugen
• Meerbeek Berent Willem
• Van Loenen Evert Jan

Classifications

• F21S8/04

  intended only for mounting on a ceiling or the like overhead structures (F21S8/02 takes precedence; {details of ceiling bases F21V21/03}) · CPC title

• F21V11/08

  using diaphragms containing one or more apertures · CPC title

• G02B6/0053

  Prismatic sheet or layer; Brightness enhancement element, sheet or layer · CPC title

• G02B6/0076

  Stacked arrangements of multiple light guides of the same or different cross-sectional area · CPC title

• E04B9/32

  Translucent ceilings, i.e. permitting both the transmission and diffusion of light ({E04B9/303 and} E04B9/34 takes precedence; lighting F21) · CPC title