Light emitting diode projection system
First Claim
1. An illumination apparatus for providing an output beam that matches the é
- tendue of a downstream application, said illumination apparatus comprisingat least one LED optical source having a predetermined é
tendue 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 é
tendue 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 optical shape to emerge from said exit aperture as a beam having substantially the same é
tendue as that of said at least one LED optical source but altered in angle and dimensions to substantially match the é
tendue of the downstream application.
1 Assignment
0 Petitions
Accused Products
Abstract
The present invention generally relates to video and/or television projection systems, and more particularly, to LED based light source systems utilizing generally non-rotationally symmetric, preferably oblong or rectangular, non-imaging collection optics for providing improved projection systems relative to arc lamp and other LED based light source systems. The non-rotationally symmetric non-imaging collection optics are configured to operate with LEDs to provide preferred, generally, uniform light distributions whose étendues match those of downstream applications such as those encountered in projection systems. Also provided are various arrangements for coupling LED output to the entrance aperture of collection optics and for coupling the outputs from a plurality of collection optic outputs to form single beams of illumination of preferred patterns, intensities, and color.
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Citations
34 Claims
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1. An illumination apparatus for providing an output beam that matches the é
- tendue of a downstream application, said illumination apparatus comprising
at least one LED optical source having a predetermined é
tendue and spectral output; andat 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 é
tendue 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 optical shape to emerge from said exit aperture as a beam having substantially the same é
tendue as that of said at least one LED optical source but altered in angle and dimensions to substantially match the é
tendue of the downstream application. - View Dependent Claims (3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26)
- tendue of a downstream application, said illumination apparatus comprising
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2. The illumination apparatus of claim wherein the cross-sectional shape of said entrance and exit apertures of said non-imaging optic and the cross-sectional shape thereof is oblong.
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27. A projection apparatus for forming video images, said projection apparatus comprising:
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at least one LED optical source having a predetermined é
tendue and spectral output;a digital device for selectively modulating light incident thereto, said digital device having a given é
tendue;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 spatially uniform beam of substantially the same é
tendue as that of said LED optical source, said non-imaging optic having an entrance aperture, an exit aperture, and a nonrotationally 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 optical shape to emerge from said exit aperture as a beam having substantially the same é
tendue as that of said at least one LED optical source but altered in angle and dimensions to substantially match the é
tendue of said digital device;a relay lens for imaging the near field from said non-imaging optic onto said digital device to form video images; a screen for viewing images formed thereon; and a projection lens for projecting said digital device onto said screen as said digital device is modulated so that video images formed thereon can be observed on said viewing screen. - View Dependent Claims (28, 29)
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30. An illumination apparatus for providing an output beam that matches the é
- tendue of a downstream application, said illumination apparatus comprising
at least one LED optical source having a predetermined é
tendue and spectral output; andat least one solid 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 spatially uniform beam of substantially the same é
tendue as that of said LED optical source, said non-imaging optic having an entrance aperture, an exit aperture, and a rotationally symmetric cross-sectional shape that continuously enlarges from said entrance to said exit aperture, said at least one LED optical source being air spaced from 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 optical shape to emerge from said exit aperture as a beam having substantially the same é
tendue as that of said at least one LED optical source but altered in angle and dimensions to substantially match the é
tendue of the downstream application. - View Dependent Claims (31, 32)
- tendue of a downstream application, said illumination apparatus comprising
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33. An LED apparatus comprising:
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a bare LED die having an emitting surface that is at least in part diffusely reflective; and a low absorption encapsulant conformally overlying said bare LED die, said low absorption encapsulant being formed of a material having an index of refraction greater than unity so as to operate to at least in part totally internally reflect light at the encapsulant air interface so that it impinges onto said diffusely reflective emitting surface after which it is at least in part transmitted back through said encapsulant air interface so that the overall output of said apparatus is increased over what it would otherwise be without said encapsulant. - View Dependent Claims (34)
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Specification