The present disclosure provides a light emitting device including a substrate, a conductive layer, first and second reflective layers, a light emitting element, and an encapsulation layer. The conductive layer is disposed on the substrate. The first reflective layer covers the conductive layer and has an opening exposing a portion of the conductive layer. The light emitting element is disposed in the opening and electrically connects to the conductive layer. The second reflective layer is disposed on the first reflective layer and surrounds the light emitting element, and the second reflective layer has an outer diameter. The encapsulation layer covers the light emitting element. There is a height between a highest point of the encapsulation layer and an upper surface of the first reflective layer, and the height is 0.1 to 0.5 times the outer diameter. The present disclosure also provides a backlight and a display panel.

A head up display apparatus for a vehicle includes an imaging unit that generates a projection light beam with display content and includes a transmissive display indication layer with selectively controllable display elements distributed over an area, a matrix backlight that provides backlighting therefor and includes selectively controllable light sources distributed along the transmissive display indication layer, and a collimation array with collimators arranged between a light source and the transmissive display indication layer, and a projection panel in the beam path of the projection light beam generated by the imaging unit for reflecting the projection light beam to a user, the projection panel being arranged in the beam path such that a virtual display image is generated therebehind in the visual field of the user.

An optical sheet 43 is built into a liquid crystal display apparatus in which a plurality of light sources 42 are dispersed on a back surface side of a display screen. One surface of the optical sheet 43 has an uneven surface. In a predetermined region R on the one surface of the optical sheet 43, a luminance enhancer 25 that improves the total light transmittance of the predetermined region R is provided so as to at least partially fill recesses 22a of the uneven surface.

A circuit board for a light-emitting diode assembly includes a substrate layer, a dimming zone column disposed on one surface of the substrate layer, the dimming zone column including dimming zones, each of the dimming zones including a predetermined number of LED landing pads. The dimming zones includes a predetermined number of first dimming zones and a predetermined number of second dimming zones, a first common wiring commonly connected to the first dimming zones and disposed at a first lateral side in a row direction of the dimming zone column, a second common wiring connected to the second dimming zones and disposed at a second lateral side in the row direction opposite to the first lateral side of the dimming zone column, and an individual wiring connected to each of the dimming zones.

A circuit board for a light-emitting diode assembly according to an embodiment includes a substrate layer, dimming zones formed on one surface of the substrate layer, each of the dimming zones comprising a predetermined number of LED landing pads, and a wiring bundle disposed between the dimming zones neighboring in a row direction to extend in a column direction, the wiring bundle including wirings connected to the LED landing pads at the same level.

A light emitting diode device includes a substrate, a reflector cup on the substrate and defining cavity, a light-emitting chip on the substrate and in the cavity, fluorescent glue filling the cavity and covering the light-emitting chip, and a phosphor film on a side of the reflector cup away from the substrate. The light-emitting chip is surrounded by the reflector cup. The fluorescent glue includes fluorescent powder and transparent glue.

The present embodiment comprises: a plurality of light-emitting units; and a reflector including reflector units having spaces formed to receive the plurality of light-emitting units, respectively. Each of the plurality of light-emitting units includes an LED package mounted on a substrate and a light diffusion layer having a groove portion formed on a surface opposite to the substrate in the LED package, wherein the outer circumference of the light diffusion layer faces the inner surface of a reflector unit. In the reflector, the plurality of reflector units are integrally formed, the spaces expand along a direction extending away from the substrate, and a wall forming each of the spaces surrounds the outer circumference of each of the LED package and the light diffusion layer.

Embodiments of the present disclosure include apparatuses and method for a stacked light emitting diode (LED) display. A stacked LED display can include a first array of LEDs that are configured to emit red light, a second array of LEDs that are configured to emit green light, and a third array of LEDs that are configured to emit blue light. The stacked LED hologram display can include a number of actuators configured to adjust a position of a first array of LEDs in a first direction and a second direction orthogonal to the first direction, adjust a position of a second array of LEDs in the first direction and the second direction, and adjust a position of a third array of LEDs in the first direction and the second direction to control the packing scheme of the LEDs.

A surface light source device includes a substrate, a plurality of light emitting devices and a light diffusion member. The light flux controlling member includes an incidence surface and an emission surface. In one light emitting device among the plurality of light emitting devices, light—emitted from the light emitting center of the light emitting element at an emission angle of 80° or less with respect to the optical axis of the light emitting element, incident on the incidence surface, and emitted from the emission surface—reaches the light diffusion member without reaching another light emitting device among the plurality of light emitting devices.

A circuit board for a light-emitting diode assembly according to an embodiment includes a substrate layer having a first surface and a second surface facing each other, a conductive circuit layer disposed on the first surface of the substrate layer and having a single-layered structure, and an insulating layer formed on the first surface of the substrate layer to cover the conductive circuit layer. Channel resistance, luminous efficiency and luminous uniformity can be improved through a side connection of a dimming zone while vias or contacts are omitted.