Luminaire and lighting method
A luminaire ( 10 ) comprises an array of lighting units ( 12 ) arranged as a plurality of regions ( 14 a - 14 e ). A reflector arrangement ( 16 ) is provided over the array of lighting units ( 12 ) for directing the light from each region ( 14 a - 14 e ) of the luminaire ( 10 ) to a different spread of light output directions. Each lighting unit ( 12 ) of at least one of the regions ( 14 a - 14 e ) comprises a first sub-unit ( 20, 22, 24 ) with a first polarised light output and a second sub-unit ( 20, 22, 24 ) with a second light output which is different from the first light output in polarisation, wherein the first and second sub-units ( 20, 22, 24 ) are independently controllable. In this way, light output in a certain range of directions can be controlled to have a desired polarisation. By actuating different sub-units ( 20, 22, 24 ), the polarisation can be dynamically controlled. Thus, a system can be set up with a desired static polarisation output pattern, or the polarisation pattern may be controlled to evolve over time, for example in response to external user, sensor or data input.
1. A luminaire comprising:
an array of lighting units, arranged as a plurality of regions, each region comprising a respective plurality of sectors; and
a reflector arrangement over the array of lighting units for directing the light from the sectors of each region of the array of lighting units to a different spread of light output directions,
wherein the reflector arrangement comprises a plurality of mutually differently oriented reflectors, each reflector of said plurality of reflectors comprises a respective flat reflector surface associated with a respective sector,
wherein each lighting unit of at least one of the regions comprises a first sub-unit with an output of polarized first light and a second sub-unit with an output of second light being different from the first light in polarization, said polarized first light either having a polarization direction parallel to said respective flat reflector surface of the reflector adjacent to its associated respective sector or having a polarization direction orthogonal to said parallel polarization direction, and
wherein the first and second sub-units are independently controllable.
2. A luminaire as claimed in claim 1 , wherein:
the first light is polarized and the second light is non-polarized; or
the first light is polarized with a first polarization direction and the second light is polarized with a second, orthogonal, polarization direction.
3. A luminaire as claimed in claim 1 , wherein each lighting unit of at least one of the regions comprises a third sub-unit with an output of non-polarized third light, wherein the polarized first light output of the first sub-unit has a first polarization direction, wherein the second sub-unit has an output of polarized second light having a second, orthogonal polarization direction, and wherein the first to third sub-units are independently controllable.
4. A luminaire as claimed in claim 2 , wherein the first polarization direction is horizontal and the second polarization direction is vertical.
5. A luminaire as claimed in claim 2 , wherein each sub-unit of said at least one of the regions comprises an LED or LED array, a total internal reflector collimator and, for those sub-units providing a polarized output, a polarizing element over the collimator.
6. A luminaire as claimed in claim 2 , wherein each sub-unit of said at least one of the regions comprises an LED or LED array and for those sub-units providing a polarized output, a polarizing element over the LED or LED array, and the lighting unit further comprises a shared total internal reflector collimator over the sub-units.
7. A luminaire as claimed in claim 5 , wherein the polarizing arrangement comprises a patterned dual brightness enhancement film.
8. A luminaire as claimed in claim 1 , wherein the regions are arranged as a plurality of concentric regions and the reflector arrangement comprises a plurality of annular reflectors each between at least some adjacent concentric regions.
9. A luminaire as claimed in claim 8 , wherein one or more concentric regions comprise a lens.
10. A luminaire as claimed in claim 9 , wherein there is no reflector between the central concentric region and the adjacent concentric region.
11. A luminaire as claimed in claim 7 , comprising 3 to 6 concentric regions.
12. A luminaire as claimed in claim 1 , comprising an outdoor luminaire housing sealed against ingress of water and/or dust, and the luminaire further comprises a controller for controlling the lighting units thereby to alter the polarization characteristics of the light output.
13. A luminaire as claimed in claim 12 , wherein the controller comprises a receiver for receiving sensor, external user or data input containing weather information, wherein the controlling is in dependence on the weather information.
14. A luminaire as claimed in claim 12 wherein the controller comprises a receiver for receiving sensor, external user or data input containing location information for a subject, wherein the controlling is in dependence on the location information.
15. A method for controlling a luminaire, which luminaire comprises:
an array of lighting units, arranged as a plurality of regions each region comprising a respective plurality of sectors; and
a reflector arrangement over the array of lighting units for directing the light from the sectors of each region of lighting unit to a different spread of light output directions wherein the reflector arrangement comprises a plurality of mutually differently oriented reflectors, each reflector of said plurality of reflectors comprises a respective flat reflector surface associated with a respective sector,
wherein each lighting unit of at least one of the regions comprises a first sub-unit with an output of polarized first light and a second sub-unit with an output of second light being different from the first light in polarization,
wherein the method comprises the steps of:
setting the polarization direction of the first light such that said polarized first light either has a polarization direction parallel to said respective flat reflector surface of the reflector adjacent to its associated respective sector or has a polarization direction orthogonal to said parallel polarization direction, and
independently controlling the first and second sub-units thereby to create a desired polarization output pattern to the different spreads of light output directions.