LIGHT EMITTING DIODES WITH LOW REFRACTIVE INDEX MATERIAL LAYERS TO REDUCE LIGHT GUIDING EFFECTS

Light emitting diodes including low refractive index layers for reducing guided light are disclosed. The light-emitting diodes include at least one n-doped layer, at least one p-doped layer, and an active region disposed between the at least one n-doped layer and the at least one p-doped layer. The active region comprises a light-emitting material. The light-emitting diode further comprises at least one low refractive index layer disposed in or around the active region. 1. A light-emitting diode comprising:at least one n-doped layer;at least one p-doped layer;an active region comprising of at least one layer of light-emitting material, disposed between the at least one n-doped layer and the at least one p-doped layer; andat least one low refractive index layer disposed within one optical wavelength of the active region, the low refractive index layer configured to substantially reduce light guiding by the active region.2. The light-emitting diode of claim 1 , wherein less than 10% of total light emitted by the light-emitting material is guided by the active region.3. The light-emitting diode of claim 1 , wherein less than 2% of total light emitted by the light-emitting material is guided by the active region.4. The light-emitting diode of claim 1 , further comprising an additional light-extracting feature.5. The light-emitting diode of claim 4 , wherein the additional light-extracting feature comprises shaping the LED into at least one of claim 4 , a cubic shape claim 4 , a triangular shape claim 4 , a tetragonal shape claim 4 , or claim 4 , a pyramidal shape.6. The light-emitting diode of claim 4 , wherein the additional light-extracting feature comprises a surface roughness from about 200 nm to about 10 μum formed on one or more surfaces of the light-emitting diode.7. The light-emitting diode of claim 1 , wherein the LED comprises a Group III-nitride material.8. The light-emitting diode of claim 7 , wherein the Group III-nitride material is characterized by a ...

LED LAMPS WITH IMPROVED QUALITY OF LIGHT

LED lamps having improved light quality are disclosed. The lamps emit more than 500 lm and more than 2% of the power in the spectral power distribution is emitted within a wavelength range from about 390 nm to about 430 nm. 1. An LED lamp comprising an LED device , wherein the LED lamp is characterized by a luminous flux of more than 500 lm , and a spectral power distribution (SPD) in which more than 2% of the power is emitted within a wavelength range from about 390 nm to about 430 nm.2. The lamp of claim 1 , wherein the luminous flux is at least 1500 lm.3. The lamp of claim 1 , wherein the lamp comprises an MR16 form factor.4. The lamp of claim 1 , wherein the lamp comprises a PAR30 lamp form factor.5. The lamp of claim 1 , wherein the LED device comprises at least one violet-emitting LED.6. The lamp of claim 5 , wherein the at least one violet-emitting LED is configured to emit more than 200W/cmat a current density of 200 A/cmat a junction temperature of 100° C. or greater.7. The lamp of claim 5 , wherein the at least one violet-emitting LED pumps at least a blue phosphor or at least one cyan phosphor.8. The lamp of claim 5 , wherein the LED device comprises at least one LED configured to emit at a wavelength other than a wavelength emitted by the at least one violet-emitting LED.9. The lamp of claim 1 , wherein a short wavelength SPD discrepancy (SWSD) for a source with a correlated color temperature (CCT) in a range 2500K to 7000K is less than 35%.10. The lamp of claim 1 , wherein a violet leak of the light source is configured to achieve a particular CIE whiteness value.11. The lamp of claim 10 , wherein the violet leak is such that a CIE whiteness of a high-whiteness reference sample illuminated by the lamp is within minus 20 points and plus 40 points of a CIE whiteness of the same sample under illumination by a CIE reference illuminant of same CCT (respectively a blackbody radiator if CCT<5000K or a D illuminant if CCT>5000K).12. The lamp of claim 10 , ...

Color shifting illuminator

A color shifting illuminator includes a first luminescent material that absorbs first incident photons having an energy greater than or equal to a first threshold energy, and emits first photons with less energy than the first incident photons. The color shifting illuminator also includes a second luminescent material that absorbs second incident photons having an energy greater than or equal to a second threshold energy, and emits second photons with less energy than the second incident photons and less energy than the first photons. The first luminescent material and the second luminescent material are included in a waveguide, and the waveguide exhibits total internal reflection for the first photons and the second photons satisfying conditions for total internal reflection. An extraction region is coupled to the waveguide to emit the first photons and the second photons.

LIGHT EMITTING DIODE WITH LOW REFRACTIVE INDEX MATERIAL LAYERS TO REDUCE LIGHT GUIDING EFFECTS

A light-emitting diode (LED) for emitting emitted light having a particular wavelength, said LED comprising: (a) at least one n-doped layer; (b) at least one p-doped layer; (c) an active region comprising at least one layer of light-emitting material disposed between said at least one n-doped layer and said at least one p-doped layer, said active region having an average refractive index, calculated by averaging the LED's refractive index across the thickness of the active region; and (d) at least one low refractive index layer disposed within said particular wavelength of said active region, said at least one low refractive index layer having a refractive index below said average refractive index and a thickness sufficient to limit light being emitted into a guided mode of said active region to no more than 10% of said emitted light. 1. (canceled)2. A device comprising:a substrate;a low-index layer comprising at least one AlInN layer overlying the substrate;an intermediate layer having a thickness, overlying the low-index layer;an active region overlying the intermediate layer, configured to emit light characterized by an optical wavelength;wherein the thickness is such that a distance between the active region and the low-index layer is less than the optical wavelength; andwherein the index of the at least one AlInN layer at the optical wavelength is at least 0.05 less than the index of GaN at the optical wavelength.3. The device of claim 2 , wherein the at least one AlInN layer is lattice-matched to GaN.4. The device of claim 2 , wherein the low-index layer is n-doped.5. The device of claim 2 , wherein the low-index layer has a homogeneous composition.6. The device of claim 2 , wherein the low-index layer has a graded composition.7. The device of claim 2 , wherein the low-index layer comprises a succession of AlInN layers and other layers.8. The device of claim 7 , wherein the succession forms a superlattice.9. The device of claim 7 , wherein the other layers ...

LIGHT EMITTING DIODE WITH LOW REFRACTIVE INDEX MATERIAL LAYERS TO REDUCE LIGHT GUIDING EFFECTS

A light-emitting diode (LED) for emitting emitted light having a particular wavelength, said LED comprising: (a) at least one n-doped layer; (b) at least one p-doped layer; (c) an active region comprising at least one layer of light-emitting material disposed between said at least one n-doped layer and said at least one p-doped layer, said active region having an average refractive index, calculated by averaging the LED's refractive index across the thickness of the active region; and (d) at least one low refractive index layer disposed within said particular wavelength of said active region, said at least one low refractive index layer having a refractive index below said average refractive index and a thickness sufficient to limit light being emitted into a guided mode of said active region to no more than 10% of said emitted light. 1. A light-emitting diode (LED) for emitting emitted light having a particular wavelength , said LED comprising:at least one n-doped layer;at least one p-doped layer;an active region comprising at least one layer of light-emitting material disposed between said at least one n-doped layer and said at least one p-doped layer, said active region having an average refractive index, calculated by averaging the refractive index across the thickness of said active region; andat least one low refractive index layer disposed within said particular wavelength of said active region, said at least one low refractive index layer having a refractive index below said average refractive index and a thickness sufficient to limit light being emitted into a guided mode of said active region to no more than 10% of said emitted light.2. The light-emitting diode of claim 1 , wherein said active region comprises a Group III-nitride material.3. The light-emitting diode of claim 1 , wherein said active region is characterized by a cumulative thickness of at least 100 nm.4. The light-emitting diode of claim 1 , wherein said at least one low refractive index ...

Light emitting diodes with low refractive index material layers to reduce light guiding effects

Color shifting illuminator

A color shifting illuminator includes a first luminescent material that absorbs first incident photons having an energy greater than or equal to a first threshold energy, and emits first photons with less energy than the first incident photons. The color shifting illuminator also includes a second luminescent material that absorbs second incident photons having an energy greater than or equal to a second threshold energy, and emits second photons with less energy than the second incident photons and less energy than the first photons. The first luminescent material and the second luminescent material are included in a waveguide, and the waveguide exhibits total internal reflection for the first photons and the second photons satisfying conditions for total internal reflection. An extraction region is coupled to the waveguide to emit the first photons and the second photons.