A light emitting device includes: a substrate; a DBR mask layer on a side of the substrate, the DBR mask layer being provided with a window exposing the substrate, the window including an opening end away from the substrate and a bottom wall end close to the substrate, and on a plane where the substrate is located, an orthographic projection of the opening end falling within an orthographic projection of the bottom wall end; and a light emitting unit. The light emitting unit includes an active layer located on a side, away from the substrate, of the DBR mask layer. Providing the window on the DBR mask layer may reduce dislocation density during epitaxial growth of the light emitting unit, and arrangement of the DBR mask layer may improve light extraction efficiency of the light emitting device.

A light emitting diode (LED) array includes bottom reflectors patterned as an array of closed shapes on a top plane of a base layer for III-N growth. A three-dimensional III-N structure is epitaxially grown around the array of closed shapes and extending above the bottom reflectors. The three-dimensional III-N structures is a contiguous crystalline structure extending across the array. A laterally grown III-N layer is formed in contact with both the reflectors and the three-dimensional III-N structures, and III-N LED layers are grown on the laterally grown layer. One or more top reflectors are grown or deposited on the III-N LED layers and located over the bottom reflectors.

A colour conversion resonator system, comprising: a first partially reflective region configured to transmit light of a first primary peak wavelength and to reflect light of a second primary peak wavelength; a second partially reflective region configured to at least partially transmit light of the first and second primary peak wavelengths and to reflect light of a third primary peak wavelength; a third partially reflective region configured to at least partially reflect light with the third primary peak wavelength; a first colour conversion resonator cavity arranged to receive input light with the first primary peak wavelength through the first partially reflective region and to convert at least some of the light of the first primary peak wavelength to provide light of the second primary peak wavelength, wherein the first colour conversion resonator cavity is arranged such that the second primary peak wavelength resonates in the first colour conversion resonator cavity and resonant light with the second primary peak wavelength is output through the second partially reflective region; and a second colour conversion resonator cavity arranged to receive input light comprising the second primary peak wavelength through the second partially reflective region and to convert at least some of the second primary peak wavelength to provide light of the third primary peak wavelength, wherein the second colour conversion resonator cavity is arranged such that the third primary peak wavelength resonates in the second colour conversion resonator cavity and resonant light with the third primary peak wavelength is output through the third partially reflective region, wherein the first colour conversion resonator cavity and the second resonator cavity are arranged partially to overlap to provide a non-overlapping portion and an overlapping portion thereby to define a first light emitting surface and a second light emitting surface respectively, wherein the first light emitting surface is arranged to provide resonant light of the second primary peak wavelength and the second light emitting surface is arranged to provide resonant light of the third primary peak wavelength.

A light emitting assembly includes a micro-LED, and a supporting substrate. The micro-LED includes a semiconductor structure and a first insulating dielectric layer. The semiconductor structure includes a first-type semiconductor laver; second-type semiconductor layer, and has a first mesa surface defined by the first-type semiconductor layer, and a second mesa surface defined by the second-type semiconductor layer. The first insulating dielectric layer covers the first and second mesa surfaces and has a first mesa covering portion that covers the first mesa surface, and two bridging arms projecting from the first mesa covering portion. The two bridging arms are located on two opposite sides of the semiconductor structure and connect with the supporting substrate so that the micro-LED is supported by the supporting substrate. The two bridging arms have a thickness which is less than a thickness of the first mesa covering portion on the first mesa surface.

A semiconductor LED includes p-doped, n-doped, and active layers, and has anode and cathode electrical contacts. The active layer extend to the side surfaces of the LED; the anode contact is on a central area of the p-doped layer and leaves peripheral regions without direct electrical coupling to the anode contact, reducing non-radiative recombination at the side surfaces. The LEDs include a front reflector with a central opening at least partly aligned with the anode contact. The LED can include front or back sets of nanostructured optical elements.

A semiconductor LED includes p-doped, n-doped, and active layers, and has anode and cathode electrical contacts. The active layer extends to the side surfaces of the LED; the anode contact is on a central area of the p-doped layer and leaves peripheral regions without direct electrical coupling to the anode contact. A back dielectric layer on peripheral portions of the anode contact surface that lack direct electrical coupling to the anode electrical contact includes a central portion opposite at least the central area of the anode contact surface. That protruding central portion protrudes away from the anode contact surface, has a tapered shape, and redirects a portion of light propagating from the active layer through the anode contact surface to propagate back through the anode contact surface toward the light-exit surface.