Abstract: In one aspect, optical elements and luminaires employing optical elements are described herein. In some embodiments, an optical element comprises a planar light transmissive body comprising a light input surface and a light output surface opposite the input surface, and light redirection features arranged over the light input surface and the light output surface, the light redirection features comprising refractive facets, reflective facets, facets supporting total internal reflection within the planar light transmissive body, or combinations thereof.

Abstract: Silicon carbide (SiC) materials including SiC wafers and SiC boules and related methods are disclosed that provide large dimension SiC wafers with reduced crystallographic stress. Growth conditions for SiC materials include maintaining a generally convex growth surface of SiC crystals, adjusting differences in front-side to back-side thermal profiles of growing SiC crystals, supplying sufficient source flux to allow commercially viable growth rates for SiC crystals, and reducing the inclusion of contaminants or non-SiC particles in SiC source materials and corresponding SiC crystals. By forming larger dimension SiC crystals that exhibit lower crystallographic stress, overall dislocation densities that are associated with missing or additional planes of atoms may be reduced, thereby improving crystal quality and usable SiC crystal growth heights.

Abstract: Lighting devices having optical waveguides for controlled light distribution are provided. A lighting device includes a housing, a light emitter disposed in the housing, and a waveguide at least partially disposed in an opening of the housing. The waveguide includes a light input surface defining coupling features, wherein the light emitter is disposed adjacent the light input surface and emits light into the coupling features. The waveguide further includes a light transmission portion disposed between the light input surface and a light extraction portion, wherein light from the light emitter received at the light input surface propagates through the light transmission portion toward the light extraction portion. The waveguide further includes the light extraction portion, which comprises at least one light redirection feature and at least one light extraction feature that cooperate to generate a controlled light pattern exiting the lighting device.

Abstract: Silicon carbide (SiC) materials including SiC wafers and SiC boules and related methods are disclosed that provide large dimension SiC wafers with reduced crystallographic stress. Growth conditions for SiC materials include maintaining a generally convex growth surface of SiC crystals, adjusting differences in front-side to back-side thermal profiles of growing SiC crystals, supplying sufficient source flux to allow commercially viable growth rates for SiC crystals, and reducing the inclusion of contaminants or non-SiC particles in SiC source materials and corresponding SiC crystals. By forming larger dimension SiC crystals that exhibit lower crystallographic stress, overall dislocation densities that are associated with missing or additional planes of atoms may be reduced, thereby improving crystal quality and usable SiC crystal growth heights.

Abstract: Lighting devices having optical waveguides for controlled light distribution are provided. A lighting device includes a housing, a light emitter disposed in the housing, and a waveguide at least partially disposed in an opening of the housing. The waveguide includes a light input surface defining coupling features, wherein the light emitter is disposed adjacent the light input surface and emits light into the coupling features. The waveguide further includes a light transmission portion disposed between the light input surface and a light extraction portion, wherein light from the light emitter received at the light input surface propagates through the light transmission portion toward the light extraction portion. The waveguide further includes the light extraction portion, which comprises at least one light redirection feature and at least one light extraction feature that cooperate to generate a controlled light pattern exiting the lighting device.

Abstract: Lighting devices having optical waveguides for controlled light distribution are provided. A lighting device includes a housing, a light emitter disposed in the housing, and a waveguide at least partially disposed in an opening of the housing. The waveguide includes a light input surface defining coupling features, wherein the light emitter is disposed adjacent the light input surface and emits light into the coupling features. The waveguide further includes a light transmission portion disposed between the light input surface and a light extraction portion, wherein light from the light emitter received at the light input surface propagates through the light transmission portion toward the light extraction portion. The waveguide further includes the light extraction portion, which comprises at least one light redirection feature and at least one light extraction feature that cooperate to generate a controlled light pattern exiting the lighting device.

Abstract: A lighting device comprises a body of optically transmissive material exhibiting a total internal reflection characteristic, the body further comprising a light input surface for receiving light, a light extraction portion spaced from the light input surface, a light transmission portion disposed between the light input surface and the light extraction portion, and at least one light deflection surface for deflecting light toward the light extraction portion. Further in accordance with this aspect the light extraction portion comprises a first extraction surface for extracting light deflected by the at least one light deflection surface out of the body and a second extraction surface for extracting light other than light deflected by the at least one light deflection surface out of the body.

Abstract: Silicon carbide (SiC) materials including SiC wafers and SiC boules and related methods are disclosed that provide large dimension SiC wafers with reduced crystallographic stress. Growth conditions for SiC materials include maintaining a generally convex growth surface of SiC crystals, adjusting differences in front-side to back-side thermal profiles of growing SiC crystals, supplying sufficient source flux to allow commercially viable growth rates for SiC crystals, and reducing the inclusion of contaminants or non-SiC particles in SiC source materials and corresponding SiC crystals. By forming larger dimension SiC crystals that exhibit lower crystallographic stress, overall dislocation densities that are associated with missing or additional planes of atoms may be reduced, thereby improving crystal quality and usable SiC crystal growth heights.

Abstract: Lighting devices having optical waveguides for controlled light distribution are provided. A lighting device includes a housing, a light emitter disposed in the housing, and a waveguide at least partially disposed in an opening of the housing. The waveguide includes a light input surface defining coupling features, wherein the light emitter is disposed adjacent the light input surface and emits light into the coupling features. The waveguide further includes a light transmission portion disposed between the light input surface and a light extraction portion, wherein light from the light emitter received at the light input surface propagates through the light transmission portion toward the light extraction portion. The waveguide further includes the light extraction portion, which comprises at least one light redirection feature and at least one light extraction feature that cooperate to generate a controlled light pattern exiting the lighting device.

Abstract: A light fixture with a troffer design. The light fixture includes a housing, LED assembly, and lens assembly. An inner lens can be positioned over the LED assembly to control the distribution of light. A reflector can be positioned over the LED assembly instead of the inner lens to control the light.

Abstract: A light fixture with a troffer design. The light fixture includes a housing, LED assembly, and lens assembly. An inner lens can be positioned over the LED assembly to control the distribution of light. A reflector can be positioned over the LED assembly instead of the inner lens to control the light.

Abstract: A troffer light fixture has a housing with a LED assembly positioned in the housing. The LED assembly includes at least one LED array comprising LEDs of at least two different colors. The LED assembly includes a first LED array having a first LED on a first string and a second LED on a second string and a second LED array having a third LED on a third string and fourth LED on a fourth string. A wide lens covers the LED array. A reflector assembly has a first reflective surface and a second reflective surface reflecting light from the at least one LED array laterally across the width of the wide lens. Alternatively, the LED array may be approximately one-half the width of the wide lens and the reflector may be eliminated.

Abstract: A troffer light fixture has a housing with a LED assembly positioned in the housing. The LED assembly includes at least one LED array comprising LEDs of at least two different colors. The LED assembly includes a first LED array having a first LED on a first string and a second LED on a second string and a second LED array having a third LED on a third string and fourth LED on a fourth string. A wide lens covers the LED array. A reflector assembly has a first reflective surface and a second reflective surface reflecting light from the at least one LED array laterally across the width of the wide lens. Alternatively, the LED array may be approximately one-half the width of the wide lens and the reflector may be eliminated.

Abstract: A troffer light fixture has a housing with a LED assembly positioned in the housing. The LED assembly includes at least one LED array comprising LEDs of at least two different colors. The LED assembly includes a first LED array having a first LED on a first string and a second LED on a second string and a second LED array having a third LED on a third string and fourth LED on a fourth string. A wide lens covers the LED array. A reflector assembly has a first reflective surface and a second reflective surface reflecting light from the at least one LED array laterally across the width of the wide lens. Alternatively, the LED array may be approximately one-half the width of the wide lens and the reflector may be eliminated.

Abstract: A lighting device comprises a body of optically transmissive material exhibiting a total internal reflection characteristic, the body further comprising a light input surface for receiving light, a light extraction portion spaced from the light input surface, a light transmission portion disposed between the light input surface and the light extraction portion, and at least one light deflection surface for deflecting light toward the light extraction portion. Further in accordance with this aspect the light extraction portion comprises a first extraction surface for extracting light deflected by the at least one light deflection surface out of the body and a second extraction surface for extracting light other than light deflected by the at least one light deflection surface out of the body.

Abstract: A lighting device, comprising a shield element and at least a first light source, the first light source within a space defined by portions of the shield element, the shield element comprising at least one vent, the shield element blocking the first light source from direct view from locations outside the shield element. Also, a lighting device, comprising a shield element and at least a first light source, the shield element comprising regions that define an opening, the first light source within a space defined by portions of the shield element and the opening. Also, a shield element.

Abstract: A lighting device comprises a body of optically transmissive material exhibiting a total internal reflection characteristic, the body further comprising a light input surface for receiving light, a light extraction portion spaced from the light input surface, a light transmission portion disposed between the light input surface and the light extraction portion, and at least one light deflection surface for deflecting light toward the light extraction portion. Further in accordance with this aspect the light extraction portion comprises a first extraction surface for extracting light deflected by the at least one light deflection surface out of the body and a second extraction surface for extracting light other than light deflected by the at least one light deflection surface out of the body.

Abstract: In one embodiment, a lamp comprises an optically transmissive enclosure. An LED array is disposed in the optically transmissive enclosure operable to emit light when energized through an electrical connection. A gas is contained in the enclosure to provide thermal coupling to the LED array. The gas may include oxygen.