Abstract: A light emitting device is disclosed and includes an emission source configured to emit a primary blue light and a wavelength-converting element configured to convert the primary blue light to a secondary light, where the wavelength-converting element including a red phosphor material having a peak emission wavelength that is less than 620 nm and a green phosphor material having a peak emission wavelength that is greater than 530 nm. The device may have a correlated color temperature (CCT) in the range of 1600K-2500K, may exhibit a melanopic/photopic ratio less than 0.25 and/or may exhibit a radiometric power fraction of light having a wavelength below 530 nm below 0.1.

Abstract: An optical coupling structures are disposed on light output surfaces of semiconductor LEDs of a miniLED or microLED array to facilitate coupling of light emitted by the semiconductor LEDs through the light output surfaces. The optical coupling structures comprise light scattering particles and/or air voids embedded in or coated with a thin layer of a material that has an index of refraction close to or matching the index of refraction of the material forming the light output surface of the semiconductor LEDs.

Abstract: In a method according to embodiments of the invention, for a predetermined amount of light produced by a light emitting diode and converted by a phosphor layer comprising a host material and a dopant, and for a predetermined maximum reduction in efficiency of the phosphor at increasing excitation density, a maximum dopant concentration of the phosphor layer is selected.

Abstract: A light emitting device comprises a first group of one or more LEDs each configured to emit light having a blue color point in the 1931 CIE x,y Chromaticity Diagram, a second group of one or more LEDs each configured to emit light having a cyan or yellow color point in the 1931 CIE x,y Chromaticity Diagram, and a third group of one or more LEDs each configured to emit light having a red color point in the 1931 CIE x,y Chromaticity Diagram.

Abstract: Embodiments include a device having a micro-LED that includes at least two, individually addressable light emitting diodes on a same substrate; a phosphor converter layer disposed on the micro-LED, the phosphor converter layer including phosphor particles having a D50 of greater than 1 ?m and less than 10 ?m.

Abstract: An optical coupling structures are disposed on light output surfaces of semiconductor LEDs of a miniLED or microLED array to facilitate coupling of light emitted by the semiconductor LEDs through the light output surfaces. The optical coupling structures comprise light scattering particles and/or air voids embedded in or coated with a thin layer of a material that has an index of refraction close to or matching the index of refraction of the material forming the light output surface of the semiconductor LEDs.

Abstract: This specification discloses pcLEDs in which the wavelength converting structure comprises one or more layers of phosphor particles disposed on a transparent substrate at high packing density. The particles are coated with an inorganic non-absorbing layer which mechanically stabilizes the phosphor particle layers and provides a thermally conductive connection between the phosphor particles. The wavelength converting structure is attached to a semiconductor LED die with the transparent substrate of the wavelength converting structure facing away from the die by a thin glue layer that bonds a light emitting surface of the die to the phosphor particle layers. Methods for fabricating such pcLEDs are also disclosed.

Abstract: A particle layer is positioned over a light output surface of a light emitting diode. A transparent protection layer positioned between and in contact with the light output surface and the particle layer. The particle layer comprises a multitude of optically scattering or luminescent particles and a thin coating layer of transparent material coating particles of the multitude. The particles are characterized by a D50 greater than about 1.0 ?m and less than about 30. ?m; the coating layer has a thickness less than about 0.20 ?m. The protection layer is less than about 0.05 ?m thick and includes one or more materials different from material of the coating layer. The protection and coating layers can each include one or more metal or semiconductor oxides. Oxide precursor reactivities, with respect to the corresponding light output surface, are less for protection layer material than for coating layer material.

Abstract: An optical coupling structures are disposed on light output surfaces of semiconductor LEDs of a miniLED or microLED array to facilitate coupling of light emitted by the semiconductor LEDs through the light output surfaces. The optical coupling structures comprise light scattering particles and/or air voids embedded in or coated with a thin layer of a material that has an index of refraction close to or matching the index of refraction of the material forming the light output surface of the semiconductor LEDs.

Abstract: The invention describes a light conversion device having a light converter, which is adapted to convert primary light to converted light, so that a peak emission wavelength of the converted light is in a longer wavelength range than a peak emission wavelength of the primary light. The light conversion device also has a reflective structure coupled to at least a part of a coupling surface of the light converter, where the reflective structure is a narrowband reflector arranged to reflect at least some of the primary light impinging on the reflective structure and to transmit at least some of the converted light impinging on the reflective structure.

Abstract: A light emitting device is disclosed and includes an emission source configured to emit a primary blue light and a wavelength-converting element configured to convert the primary blue light to a secondary light, where the wavelength-converting element including a red phosphor material having a peak emission wavelength that is less than 620 nm and a green phosphor material having a peak emission wavelength that is greater than 530 nm. The device may have a correlated color temperature (CCT) in the range of 1600K-2500K, may exhibit a melanopic/photopic ratio less than 0.25 and/or may exhibit a radiometric power fraction of light having a wavelength below 530 nm below 0.1.

Abstract: A light emitting device comprises a first group of one or more LEDs each configured to emit light having a blue color point in the 1931 CIE x,y Chromaticity Diagram, a second group of one or more LEDs each configured to emit light having a cyan or yellow color point in the 1931 CIE x,y Chromaticity Diagram, and a third group of one or more LEDs each configured to emit light having a red color point in the 1931 CIE x,y Chromaticity Diagram.

Abstract: A particle layer is positioned over a light output surface of a light emitting diode. A transparent protection layer positioned between and in contact with the light output surface and the particle layer. The particle layer comprises a multitude of optically scattering or luminescent particles and a thin coating layer of transparent material coating particles of the multitude. The particles are characterized by a D50 greater than about 1.0 ?m and less than about 30. ?m; the coating layer has a thickness less than about 0.20 ?m. The protection layer is less than about 0.05 ?m thick and includes one or more materials different from material of the coating layer. The protection and coating layers can each include one or more metal or semiconductor oxides. Oxide precursor reactivities, with respect to the corresponding light output surface, are less for protection layer material than for coating layer material.

Abstract: Embodiments include a device having a component with a component surface; a phosphor converter body with a phosphor converter body surface facing the component surface; a plurality of particles between and in contact with the component surface and the phosphor converter body surface; and an inorganic coating on and in contact with at least a portion of the particles, at least a portion of the component surface, and at least a portion of the phosphor converter body surface, and a method making such device.

Abstract: A light emitting diode (LED) device may include an LED die having a first surface on a substrate. A first phosphor layer may be formed on a second surface and sides of the LED die. The second surface may be opposite the first surface. A second phosphor layer may be formed on the first phosphor layer. The second phosphor layer may have a peak emission wavelength (Lpk2) located between a peak emission wavelength of the LED die (LpkD) and a peak emission wavelength of the first phosphor layer (Lpk2).

Abstract: A light emitting device is disclosed and includes an emission source configured to emit a primary blue light and a wavelength-converting element configured to convert the primary blue light to a secondary light having a correlated color temperature (CCT) in the range of 1600K-2500K and color rendering index (CRI) in the range of 40-60, the wavelength-converting element including a red phosphor material having a peak emission wavelength that is less than 620 nm and a green phosphor material having a peak emission wavelength that is greater than 530 nm. The device may exhibit a melanopic/photopic ratio of less than 0.25 and/or may exhibit a radiometric power fraction of light having a wavelength below 530 nm below .1.

Abstract: A disclosed light-emitting device may provide white light with a cyan gap coinciding with a melanopic sensitivity range and thus having reduced melanopic content. The disclosed light-emitting device may include a light source providing violet or blue light with a peak wavelength under 450 nanometers (nm). The disclosed light-emitting device may include at least one down-converter coupled to and located downstream of the light source and configured with a long-wavelength onset to convert the spectrum of the violet or blue light to generate white light with a spectral power content in a 447-531 nm wavelength range that is less than or equal to 10% of a total spectral power content in a 380-780 nm wavelength range. The disclosed light-emitting device may be incorporated in a light engine system that further includes a control system that controls a drive current to the light-emitting device.

Abstract: A light emitting device comprises a first group of one or more LEDs each configured to emit light having a blue color point in the 1931 CIE x,y Chromaticity Diagram, a second group of one or more LEDs each configured to emit light having a cyan or yellow color point in the 1931 CIE x,y Chromaticity Diagram, and a third group of one or more LEDs each configured to emit light having a red color point in the 1931 CIE x,y Chromaticity Diagram.

Abstract: The invention describes a light conversion device comprising: a light converter, wherein the light converter is adapted to convert primary light to converted light, wherein a peak emission wavelength of the converted light is in a longer wavelength range than a peak emission wavelength of the primary light, a reflective structure coupled to at least a part of a coupling surface of the light converter, wherein the reflective structure is a narrowband reflector in the sense that is arranged to reflect at least 55% of the primary light impinging on the reflective structure and to transmit at least 50% of the converted light impinging on the reflective structure. The invention further describes a laser-based light source comprising such a light conversion device. The invention further relates to a vehicle headlight comprising the laser-based light source.

Abstract: The invention provides a lighting device configured to provide white lighting device light, the lighting device comprising (i) a light source, configured to provide blue light source light, and (ii) a luminescent material element, configured to absorb at least part of the blue light source light and to convert into luminescent material light, wherein the luminescent material element comprises a luminescent material which consists for at least 80 wt. % of a M2-2xEu2xSi5-yAlyOyN8-y phosphor, wherein M comprises one or more of Mg, Ca, Sr, Ba, with a molar ratio of (Mg+Ca+Sr)/(Ba)?0.1, wherein x is in the range of 0.001-0.02, wherein y is in the range of ?0.2, and wherein the white lighting device light comprises said blue light source light and said luminescent material light.