A solar disk light has a disk light body, the disk light body including a housing and a lid over the housing, the housing being hollow to contain components of the disk light. The disk light body has solar cells on an outer surface thereof for harvesting solar energy and detecting ambient light, and LEDs for emitting light. The LEDs are adapted to be selectively driven to emit cool temperature light or warm temperature light. The wiring and driver electronics configured to deliver electrical power to the LEDs from the battery, and configured to drive some or all of the LEDs to emit warm light or cool light depending on a switch setting or signals received from a remote-control transmitter.

A solar disk light has a disk light body, the disk light body including a housing and a lid over the housing, the housing being hollow to contain components of the disk light. The disk light body has solar cells on an outer surface thereof for harvesting solar energy and detecting ambient light, and LEDs for emitting light. The LEDs are adapted to be selectively driven to emit cool temperature light or warm temperature light. The wiring and driver electronics configured to deliver electrical power to the LEDs from the battery, and configured to drive some or all of the LEDs to emit warm light or cool light depending on a switch setting or signals received from a remote-control transmitter.

A front-mounted high-voltage LED light source for supplementing light to plants includes a substrate, a high-voltage LED chip set, a first layer of glue powder and a second layer of glue powder. By controlling a weight ratio of the transparent adhesive medium and the red fluorescent particles in the first layer of glue powder, as well as thickness of the first layer of glue powder; and, by controlling a weight ratio of the transparent adhesive medium and the yellow fluorescent particles in the second layer of glue powder, as well as the thickness of the second layer of glue powder, a ratio range of photon number of red light, blue light to green light emitted by the front-mounted high-voltage LED light source for supplementing light to plants per a unit time is (65-95):(5-30):(5-25).

An emitter, in particular a lamp, and a method for emitting light are described. The emitter comprises at least one LED element for producing electromagnetic radiation in a first frequency range and an active cooling unit for cooling the at least one LED element, having at least one cooling channel for a coolant. The at least one cooling channel is arranged at least partially in a beam path of the electromagnetic radiation produced by the at least one LED element. The coolant comprises at least one phosphor for converting at least a part of the electromagnetic radiation into light to be emitted in a second frequency range, which is different from the first frequency range.

An emitter, in particular a lamp, and a method for emitting light are described. The emitter comprises at least one LED element for producing electromagnetic radiation in a first frequency range and an active cooling unit for cooling the at least one LED element, having at least one cooling channel for a coolant. The at least one cooling channel is arranged at least partially in a beam path of the electromagnetic radiation produced by the at least one LED element. The coolant comprises at least one phosphor for converting at least a part of the electromagnetic radiation into light to be emitted in a second frequency range, which is different from the first frequency range.

A light emitting device includes one or more light emitting elements and a plurality of fluorescent materials, and emits a first light, a second light, and a third light, wherein the first light has a correlated color temperature between 1,500 K and 3,500 K and a color rendering index R9 of 50 or more, the second light has a correlated color temperature between 3,500 K and 5,500 K and a color rendering index R9 of 50 or more, the third light has values of X and Y coordinates in the chromaticity diagram of the CIE1931 color system smaller than the values of X and Y coordinates at a color temperature of 5,500 K on the black body radiation locus, and a light having a correlated color temperature of 6,500 K has a color rendering index R9 of 50 or more and a melanopic ratio of 1.0 or more.

A light emitting device includes one or more light emitting elements and a plurality of fluorescent materials, and emits a first light, a second light, and a third light, wherein the first light has a correlated color temperature between 1,500 K and 3,500 K and a color rendering index R9 of 50 or more, the second light has a correlated color temperature between 3,500 K and 5,500 K and a color rendering index R9 of 50 or more, the third light has values of X and Y coordinates in the chromaticity diagram of the CIE1931 color system smaller than the values of X and Y coordinates at a color temperature of 5,500 K on the black body radiation locus, and a light having a correlated color temperature of 6,500 K has a color rendering index R9 of 50 or more and a melanopic ratio of 1.0 or more.

A wavelength conversion device (100) comprises: a substrate (110), a reflective layer (120) on the substrate (110) and a wavelength conversion layer (130) on the reflective layer (120). The reflective layer (120) comprises a binder (121) and reflective titanium dioxide nanoparticles (122). The nanoparticles (122) have a particle size of about 200 nanometers to about 500 nanometers. The reflective layer (120) has enhanced thermal stability. Methods of manufacture the wavelength conversion device are also disclosed.

A wavelength conversion device (100) comprises: a substrate (110), a reflective layer (120) on the substrate (110) and a wavelength conversion layer (130) on the reflective layer (120). The reflective layer (120) comprises a binder (121) and reflective titanium dioxide nanoparticles (122). The nanoparticles (122) have a particle size of about 200 nanometers to about 500 nanometers. The reflective layer (120) has enhanced thermal stability. Methods of manufacture the wavelength conversion device are also disclosed.

A wavelength conversion device (100) comprises: a substrate (110), a reflective layer (120) on the substrate (110) and a wavelength conversion layer (130) on the reflective layer (120). The reflective layer (120) comprises a binder (121) and reflective titanium dioxide nanoparticles (122). The nanoparticles (122) have a particle size of about 200 nanometers to about 500 nanometers. The reflective layer (120) has enhanced thermal stability. Methods of manufacture the wavelength conversion device are also disclosed.