Solid state light fixture with a tunable angular distribution

摘要

A light fixture may include LEDs that each emits light into a particular zone on a lens, where each zone has its own focal properties. Each LED may be grouped into one (or more) subset(s) that corresponds to the zone(s) struck by its emitted light. The LEDs may be selectively electrically controllable, so that the amount of light transmitted through each zone may be controllable by the electrical control system of the fixture. Because light transmitted through different zones emerges from the fixture having different widths, the electrical control system can directly control the amount of light emerging at each width. By mixing relatively narrow light with relatively wide light in the proper proportions, the electrical control system of the fixture may produce light having any desired angular profile between “narrow” and “wide”.

主权项

1. A light fixture, comprising:
a lens having a lateral area divided into a plurality of zones, each zone having a respective focal length; a plurality of selectively electrically controllable light emitting diodes (LEDs) disposed longitudinally adjacent to the lens, the plurality of LEDs emitting light in essentially the same direction toward the lens with essentially the same spectral profile, each LED in the plurality emitting light that strikes one of the zones, each LED belonging to a subset of LEDs corresponding to the zone struck by its emitted light, each zone producing a transmitted beam having a respective angular beam width, the transmitted beams from the plurality of zones forming exiting light; wherein at least two of the zones produce transmitted beams having different respective angular beam widths; wherein each subset of LEDs is electrically controllable independent of the other subsets; wherein the zones are concentric with each consecutive zone completely surrounding the respective zone of the beam having a narrower angular beam width; and wherein a variation in electrical power to one subset of LEDs relative to the other subsets of LEDs produces an adjustment of an angular beam width of the fixture.