Daylight sensing arrangement for a hybrid luminaire

Patent metadata

Field	Value
Publication number	US-9322525-B2
Application number	US-201214234504-A
Country	US
Kind code	B2
Filing date	Jul 9, 2012
Priority date	Jul 25, 2011
Publication date	Apr 26, 2016
Grant date	Apr 26, 2016

Abstract

The disclosed embodiments relate to a daylight harvesting system ( 1 ). The daylight harvesting system comprises a light distribution device comprising a light inlet ( 2 ) for receiving incident light ( 3 ), and a light outlet ( 4 ) for providing output light ( 5 ) received by the light inlet into an interior space. A light sensor ( 6 ) is arranged to receive and measure a light level of the incident light and to provide a measurement signal representative thereof. Control circuitry ( 7 ) is arranged to receive the measurement signal, and to provide a control signal based on the measurement signal to an artificial light source ( 8 ) placed at the light outlet. The light sensor is placed relative the light inlet such that the incident light received by the light sensor exclusively is affected by the incident light as received by the light inlet.

First claim

The invention claimed is:

1. A daylight harvesting system, comprising:
a light distribution device comprising a light inlet for receiving incident light, and a light outlet for providing output light received by the light inlet into an interior space,
a light sensor arranged to receive and measure a light level of the incident light and to provide a measurement signal representative thereof, wherein the light sensor is placed relative the light inlet such that the incident light received by the light sensor exclusively is affected by the incident light as received by the light inlet,
control circuitry arranged to receive the measurement signal, and to provide a control signal based on the measurement signal to an artificial light source placed at the light outlet, and
a shadow casting element arranged to block direct light of the incident light to provide an area comprising indirect light, wherein at least a first sub-area of the area comprises direct and indirect light and at least a second sub-area of the area exclusively comprises indirect light, and wherein the light sensor is arranged to receive and measure the light of the first sub-area and the second sub-area, respectively.

2. The daylight harvesting system according to claim 1 , further comprising a reflective surface upon which the area is formed, and wherein the light sensor is an image sensor arranged to image the reflective surface.

3. The daylight harvesting system according to claim 2 , wherein the reflective surface is tiltedly arranged in relation to a substantially horizontal plane.

4. The daylight harvesting system according to claim 1 , wherein the shadow casting element is a part of the light sensor.

5. The daylight harvesting system according to claim 1 , wherein the light sensor is arranged to determine a difference in direct light contribution between at least the first sub area and the second sub-area.

6. The daylight harvesting system according to claim 1 , wherein the light sensor comprises at least one filter that matches light responsivity of a human eye.

7. The daylight harvesting system according to claim 1 , wherein the light distribution device further comprises light transporting means arranged to transport light from the light inlet to the light outlet, and wherein the light transporting means comprises one from a window, a light tube or a fibre optical cable.

8. The daylight harvesting system according to claim 1 , further comprising a dome, and wherein the light sensor is arranged between the dome and the light inlet.

9. The daylight harvesting system according to claim 1 , further comprising the artificial light source arranged to receive the control signal, and wherein the artificial light source is arranged to provide light as a function of the control signal.

10. The daylight harvesting system according to claim 1 , wherein the light sensor further is placed relative the light inlet such that the incident light received by the light sensor further has essentially the same direct light contribution as the incident light that enters the light inlet.

11. The daylight harvesting system according to claim 1 , wherein the light sensor is arranged to provide the control signal to a plurality of artificial light sources, each artificial light source of the plurality of artificial light sources being arranged at individual light outlets.

12. A luminaire comprising at least one daylight harvesting system according to claim 1 .

13. A lighting control system comprising at least one daylight harvesting system according to claim 1 .

Assignees

• Gommans Hendrikus Hubertus Petrus
• Meijer Eduard Johannes
• Koninkl Philips Nv

Inventors

• Gommans Hendrikus Hubertus Petrus
• Meijer Eduard Johannes

Classifications

• F21S19/005 Primary

  Combining sunlight and electric light sources for indoor illumination · CPC title

• H05B47/11 Primary

  by determining the brightness or colour temperature of ambient light · CPC title

• Y02B20/46

  Cross-Sectional Technologies · mapped topic

• H05B37/0218

  Electricity · mapped topic

• Y02B20/40

  Control techniques providing energy savings, e.g. smart controller or presence detection · CPC title