Patent ID: 8403527

Claim:
A lighting apparatus for providing area illumination of high uniformity and power density, said lighting apparatus comprising: a high thermal conductivity printed circuit board; at least one bare LED die comprising one or more LED emitting areas for generating radiation of one or more spectral bands over a predetermined solid angle, said at least one bare LED die being attached to said high thermal conductivity printed circuit board with a thermally conductive bonding layer; an electronic control module attached to said high thermal conductivity printed circuit board for controlling the output of said LED emitting areas; at least one non-imaging concentrator fixedly attached to and in registration with said high thermal conductivity printed circuit board, said non-imaging concentrator having entrance and exit apertures, said non-imaging concentrator entrance aperture being optically aligned with said LED emitting areas for collecting radiation from said LED emitting areas and re-emitting it through said non-imaging concentrator exit aperture with an étendue substantially the same as that of said LED emitting areas, said non-imaging concentrator operating to homogenize the LED output to provide at the non-imaging collection optics exit aperture a high degree of near field intensity uniformity and a reduced far field extent substantially preserving the étendue of the LED output; and a relay lens for reimaging the near field of said non-imaging collector optics to an illumination plane a predetermined distance away from said non-imaging concentrator exit aperture.