Lighting system and a method of controlling a lighting system

• US 9,668,312 B2
• Filed: 09/25/2014
• Issued: 05/30/2017
• Est. Priority Date: 10/02/2013
• Status: Active Grant

• Current Assignee: Signify Holding B.V. (Signify N.V.)
• Original Assignee: Philips Lighting BV (Koninklijke Philips N.V.)
• Inventors: Meerbeek, Berent Willem, Van Boven, Jacobus Dingenis Machiel, Van Loenen, Evert Jan, Van Gheluwe, Jochen Renaat, Seuntiens, Petrus Johannes Hendrikus
• Primary Examiner(s): Philogene, Haissa
• Application Number:
  US15/026,480
• Publication Number:
  US 20160227618A1
• Time in Patent Office: 978 Days
• Field of Search: 315149, 315159, 315294, 315297, 315307, 315312, 315360, 362227, 362231, 362464, 362543, 362545
• CPC Class Codes: F21S 10/00 Lighting devices or systems producing a varying lighting effect
• CPC Class Codes: F21V 14/06 by movement of refractors in vehicle head lamps F21S41/635
• CPC Class Codes: F21V 5/045 the lens having discontinuous faces, e.g. Fresnel lenses
• CPC Class Codes: F21V 7/0091 using total internal reflection
• CPC Class Codes: F21Y 2113/17 forming a single encapsulated light source
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H05B 45/00 Circuit arrangements for operating light-emitting diodes [LED]
• CPC Class Codes: H05B 45/10 Controlling the intensity of the light
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 45/24 using electrical feedback from LEDs or from LED modules
• CPC Class Codes: H05B 47/11 by determining the brightness or colour temperature of ambient light
• CPC Class Codes: H05B 47/155 Coordinated control of two or more light sources
• CPC Class Codes: H05B 47/16 by timing means
• CPC Class Codes: Y02B 20/40 Control techniques providing energy savings, e.g. smart controller or presence detection

Abstract

A lighting system uses an array of lighting elements which provide light in different directions. The intensity of the lighting elements is controlled in dependence on a time-varying parameter related to at least one of a position of a light emitting or light reflecting body, and an intensity, color or color temperature of the light emitted or reflected by the body, such that the system can simulate directional sunlight.

Claims

1. A lighting system comprising:

a lighting unit having an array of lighting elements arranged to emit light through a light exit aperture of the lighting unit, wherein different lighting elements are arranged to provide light in different directions through the light exit aperture; and

a controller,

wherein the controller is adapted to control the lighting elements in dependence on a time-varying parameter related to at least one of a position of an orbital body, and an intensity, color or color temperature of the light emitted or reflected by the orbital body, such that a first lighting element which provides light in a direction corresponding to the position of the orbital body is brighter than a second lighting element providing light in a direction offset from the direction corresponding to the position of the orbital body.

2. A lighting system as claimed in claim 1, further comprising:

a second array of lighting elements each arranged to emit light in the same range of output directions through the light exit aperture.

3. A lighting system as claimed in claim 2, wherein the lighting elements of the second array have a color point with a greater blue component than the color point of the lighting elements of the first array.

4. A system as claimed in claim 1, wherein the first lighting element has a light emission spectrum which is different to the light emission spectrum of the second lighting element.

5. A system as claimed in claim 1, wherein the time-varying parameter takes into account the time of day, and optionally also:

the time within the year and/or

the geographical location of the system and/or

the weather conditions at the location of the system.

6. A system as claimed in claim 1, wherein different lighting elements have light outputs with different color points, such that lighting elements having a directly downward light output direction through the exit aperture have a higher color temperature than lighting elements with a light output direction offset from the downward direction.

7. A system as claimed in claim 1, wherein the array of lighting elements comprise a matrix of lighting elements provided on a convex curved support facing the light output aperture.

8. A system as claimed in claim 1, wherein the array of lighting elements comprise a matrix of lighting elements provided on a planar support, wherein each lighting element comprises a light source and an arrangement for setting the light output direction.

9. A system as claimed in claim 8, wherein the arrangement comprises:

a support surface for each lighting element, with different support surfaces tilted at different angles, and a light collimator associated with each lighting element;

or

a beam shaping optical arrangement associated with each lighting element with different beam shaping elements providing different directional output;

or

a beam shaping optical arrangement associated with each lighting element with different relative positions of identical beam shaping elements with respect to their associated lighting elements providing different directional output;

or

a collimator associated with each lighting element and a shared Fresnel lens providing different directional output.

10. A lighting system as claimed in claim 2, wherein the lighting elements of the second array have a controllable color point.

11. A method of controlling a lighting system, comprising:

detecting a time-varying parameter or receiving an input of a time varying parameter;

deriving a position of an orbital body from the time-varying parameter; and

controlling a lighting unit to emit light through a light exit aperture of the lighting unit, with different lighting elements providing light in different directions through the light exit aperture,

wherein the method further comprises controlling the intensity of the lighting elements in dependence on the position of the orbital body, such that a first lighting element which provides light in a direction corresponding to the direction from the position of the orbital body is brighter than a second lighting element providing light in a direction offset from the direction corresponding to the direction from the position of the orbital body.

12. A method as claimed in claim 11, comprising:

controlling the first lighting unit to have the brightest intensity and controlling other lighting units with reduced intensity in dependence on their distance from the first lighting unit.

13. A method as claimed in claim 11, wherein the time-varying parameter takes into account the time of day, and optionally also the time within the year and/or the geographical location of the system.