Patent ID: 7832878

Claim:
An illumination apparatus for providing an output beam that matches the étendue of a downstream application, said illumination apparatus comprising at least one LED optical source having a predetermined étendue and spectral output; and at least one non-imaging optic for collecting substantially all of the light emitted by said at least one LED optical source and re-emitting it as a beam of substantially the same étendue as that of said LED optical source, said non-imaging optic having an entrance aperture, an exit aperture, and a non-rotationally symmetric cross-sectional shape that continuously enlarges from said entrance to said exit aperture, said at least one LED optical source being positioned at and fully across said entrance aperture so that said entrance aperture is substantially uniformly filled by said output of said LED optical source, said output of said at least one LED optical source being directed by said non-imaging optic shape to emerge from said exit aperture as a beam having substantially the same étendue as that of said at least one LED optical source but altered in angle and dimensions to substantially match the étendue of the downstream application, wherein said shape is rectangular to provide said beam with a near field that is also rectangular and wherein said non-imaging optic has at least two profiles of different shape as seen in planes mutually orthogonal to its longitudinal optical axis.