Directional linear light source
View Patent ↗An illumination apparatus includes a linear array of light emitting diode (LED) chips disposed on a support. A linear reflector assembly has a light coupling reflector portion and a one dimensional light collimation or focusing portion. The linear reflector assembly is secured to the support parallel with the linear array of LED chips. An encapsulant is disposed in the light coupling reflector portion of the linear reflector assembly and pots the LED chips. An elongate phosphor element is disposed over the encapsulant such that the light coupling reflector portion and the encapsulant enhance light coupling between the LED chips and the elongate phosphor element, and the one-dimensional light collimation or focusing portion one-dimensionally collimates or focuses light emitted by the combination of the LED chips and the elongate phosphor element.
1. An illumination apparatus comprising:
an elongate phosphor element;
a linear array of light emitting diode (LED) chips spaced apart from and arranged to optically energize the elongate phosphor element, the elongate phosphor element and the linear array of LED chips defining a common plane that intersects both the elongate phosphor element and the linear array of LED chips; and
an asymmetric focusing reflector arranged to one-dimensionally focus wavelength converted light generated by the elongate phosphor element responsive to energizing by the linear array of LED chips
wherein the asymmetric focusing reflector linearly focuses the wavelength converted light outside of the common plane intersecting both the elongate phosphor element and the linear array of LED chips.
2. The illumination apparatus as set forth in claim 1 , further comprising:
a linear waveguiding element disposed in a gap between the elongate phosphor element and the spaced apart linear array of LED chips, the linear waveguiding element spreading light from the LED chips and coupling said light substantially uniformly along the elongate phosphor element.
3. The illumination apparatus as set forth in claim 1 , wherein the asymmetric focusing reflector comprises a TIR reflector.
4. The illumination apparatus as set forth in claim 1 , wherein the elongate phosphor element is generally planar with said plane arranged generally transverse to the common plane intersecting the elongate phosphor element and the linear array of LED chips.
5. The illumination apparatus as set forth in claim 1 , wherein the linear array of LED chips is disposed outside of the asymmetric focusing reflector.
6. The illumination apparatus as set forth in claim 5 , wherein the elongate phosphor element is secured together with the asymmetric focusing reflector at a focus or light input aperture of the asymmetric focusing reflector.
7. The illumination apparatus as set forth in claim 1 , wherein the asymmetric focusing reflector is a TIR reflector, and the elongate phosphor element includes a coating disposed on a light input surface of the asymmetric focusing TIR reflector.
8. The illumination apparatus as set forth in claim 1 , wherein a portion of light from the LED chips does not energize the elongate phosphor element, and the elongate phosphor element comprises:
light scattering particles that scatter the portion of light from the LED chips not energizing the elongate phosphor element, the asymmetric focusing reflector one-dimensionally focusing the scattered portion of light from the LED chips that does not energize the elongate phosphor element.
9. An illumination apparatus comprising:
a linear array of light emitting diode (LED) chips disposed on a support;
a linear reflector assembly having a light coupling reflector portion and an asymmetric one-dimensional focusing portion wherein the light coupling reflector portion and the asymmetric one-dimensional focusing portion of the linear reflector assembly are integrally formed as a single piece, the linear reflector assembly being secured to the support parallel with the linear array of LED chips;
an encapsulant disposed in the light coupling reflector portion of the linear reflector assembly and potting the LED chips; and
an elongate phosphor element disposed over the encapsulant such that the light coupling reflector portion and the encapsulant enhance light coupling between the LED chips and the elongate phosphor element and the asymmetric one-dimensional focusing portion linearly focuses light emitted by the combination of the LED chips and the elongate phosphor element outside of a common plane intersecting both the elongate phosphor element and the linear array of LED chips.
10. The illumination apparatus as set forth in claim 9 , further comprising:
a light-transmissive cover plate disposed over an open end of the asymmetric or one-dimensional focusing portion of the linear reflector assembly, the light-transmissive cover plate cooperating with the linear reflector assembly to seal the elongate phosphor element.
11. The illumination apparatus as set forth in claim 9 , wherein the linear array of LED chips emit violet or ultraviolet light and the elongate element phosphor converts the violet or ultraviolet light to an emission appearing as white light.