86results about How to "Low light efficiency" patented technology

An LED package is disclosed herein. The disclosed LED package comprises a base having an LED chip mounted thereon, an encapsulation member formed by a light-transmittable resin to encapsulate the LED chip, and a housing formed to expose a top portion of the encapsulation member and to encompass a side surface of the encapsulation member, wherein the encapsulation member is formed by a transfer molding process using a mold to have a predetermined shape. Further, the housing may be light-transmittable.

The invention discloses a PC (Polycarbonate) material with an excellent transparent light diffusion function and a preparation method thereof. The PC material is composed of polycarbonate, flame retardant masterbatch, an auxiliary flame retardant, a compound light diffuser, an antioxidant, a flame retardant synergist, a lubricant and other auxiliaries. The principle ingredient of the PC material is PC resin; the PC material is extruded by two steps, wherein the first step is to blend a sulfonate type major flame retardant and an organic silicon flame retardant with the PC resin by melting and granulate the mixture through extrusion by virtue of a twin-screw extruder so as to obtain the light diffusible flame retardant masterbatch, and the second step is to add the compound light diffuser, the flame retardant masterbatch, the antioxidant, the flame retardant synergist, the lubricant and other auxiliaries for further melting blending by taking PC as the major ingredient, and then extrude and granulate the mixture. The flame-retardant light diffusible PC material provided by the invention can be widely applied to an LED (Light-Emitting Diode) lamp, the backlight of a liquid crystal display, a transmission type screen, a decorative lighting billboard, an advertisement lamp box and the like in the lighting field.

Compensation needed to be made for reduced light efficiency in aged sub-pixels of an active matrix organic light-emitting diode (OLED) display are determined using a current ratio or a voltage ratio pertaining to an aged sub-pixel relative to un-aged, reference sub-pixels.

A rain sensor mounted on a windshield of a vehicle comprises: a housing having an opening, at least an emitter disposed in the housing and used for emitting light beams, a coupler, and an optical detector. The coupler connecting and covering the opening of the housing, comprises: at least a collimator receiving and collimating the light beams into collimated light beams; and at least a groove having a deflection surface to reflect the collimated light beams that passes through the collimator and is incident to the deflection surface at an incident angle θ to the windshield. The optical detector disposed in the housing is used for receiving the collimated light beams reflected by the windshield and generating electrical signals. The present invention characterized in that the incident angle θ satisfies the following condition: 1.27<n*sin θ<1.52, wherein n is refractive index of the coupler.

A display panel includes a light-emitting layer, a protective layer, a reflective layer, and a reflective surface. The protective layer is deposited on an emitting side of the light-emitting layer and forms an interface with an external medium. The protective layer has a thickness that allows the light emitted from the light-emitting layer to undergo total reflection at least once at the interface in an area of the light-emitting layer. The reflective layer is deposited on an opposite side of the protective layer with respect to the light-emitting layer. The reflective surface is at a periphery of the light-emitting layer and changes the direction of the light propagating inside the protective layer emitted from the light-emitting layer.

The present invention provides a nitride semiconductor device comprising an active layer of a quantum well structure, a first conductive clad layer and a second conductive clad layer. The first conductive clad layer is made of the quaternary nitride semiconductor InAlGaN having a lattice constant equal to or larger than that of the active layer and includes a first nitride semiconductor layer having an energy band gap larger than that of the active layer, a second nitride semiconductor layer having an energy band gap smaller than that of the first nitride semiconductor layer and a third nitride semiconductor layer having an energy band gap larger than that of the second nitride semiconductor layer, sequentially closer to the active layer.

The present invention provide a surface light source, wherein, the surface light source comprises a LED light source, the diffusion plate and condenser plant. The diffusion plate has a phosphor, and the diffusion plate and the LED light source are disposed separately to form a heat dissipation space. The condenser device disposes between the LED light source and the diffuser plate for converging the light emitted from LED light source to the diffusion plate.

Therefore, in the present invention, the phosphor is far away from the LED light source to avoid the heat generated by the LED chip directly transmitting to the phosphor such that the heat received by the phosphor is reduced, decreasing the temperature of the phosphor, and avoiding that the lighting efficiency of the phosphor become lower due to high temperature, and improve the color shill problem of the LED light source with manufacturing processes so as to increase the optical efficiency and optical quality of the surface light source and the display device using the same.

An illumination apparatus, including: multiple LEDs; and a lens unit that is placed correspondingly to the respective LEDs, wherein the lens unit includes a transmission lens, a first total-reflection lens, and a second total-reflection lens, wherein an incidence surface and an emission surface of the transmission lens, as well as incidence surfaces, emission surfaces and total-reflection surfaces of the first total-reflection lens and the second total-reflection lens are two-axis anamorphic aspherical surfaces, a microlens array is formed on at least one of the incidence surface and the emission surface of the transmission lens, a microlens array is formed on at least one of the emission surfaces, the total-reflection surfaces and the incidence surfaces of the first total-reflection lens and the second total-reflection lens, and the microlens arrays each have a structure in which microlenses are periodically arrayed, and are arrayed along the vertical and horizontal directions of the illumination apparatus.

The invention discloses a gallium nitride-based LED epitaxial wafer and a manufacturing method thereof, and belongs to the technical field of semiconductors. The gallium nitride-based LED epitaxial wafer includes a substrate, and a group including a buffer layer, an undoped GaN layer, an N-type layer, a multi-quantum well layer, an electron barrier layer, a P-type layer, and a P-type contact layerwhich are successively grown on the substrate, wherein the multi-quantum quantum well layer comprises alternately grown InGaN quantum well layers and composite quantum barrier layers; each compositequantum barrier layer comprises a first quantum barrier layer, a second quantum barrier layer and a third quantum barrier layer which are successively stacked; the first quantum barrier layer and thethird quantum barrier layer are both AlInGaN layers; the second quantum barrier layer is an AlGaN layer; and the Al components in the second quantum barrier layer gradually increases and then gradually decreases along the stacking direction of the epitaxial wafer. The LED epitaxial wafer provided by the invention can suppress a decrease in the luminous efficiency of the LED under large current injection and improve the luminous efficiency of the LED.

A light emitting device includes a pair of electrodes facing to each other and a phosphor layer which is sandwiched between the pair of electrodes and includes phosphor particles placed therein. The phosphor particles include an n-type nitride semiconductor part and a p-type nitride semiconductor part, the n-type nitride semiconductor part and the p-type nitride semiconductor part are made of respective single crystals having wurtzite-type crystal structures having c axes parallel with each other, and the phosphor particles include an insulation layer provided to overlie one end surface out of their end surfaces perpendicular to the c axes.

A constant-current-drive LED module device includes a rectifier configured to receive and rectify an alternating current power source; a unidirectional LED module unit configured to connect to one end of the rectifier; and a constant current unit configured to connect between the unidirectional LED module unit and the other end of the rectifier to control constant current.

The invention relates to the technical field of collimating optical system of LED lighting, in particular to a turn-back type LED lighting optical system. The turn-back type LED lighting optical system comprises a free curved-surface lens and a free curved-surface reflector. The free curved-surface lens and the free curved-surface reflector are coaxial with the spacing ranging from 0.01m to 0.1m; the free curved-surface lens comprises a first curved surface, a second curved surface, a third curved surface, a fifth curved surface and a fourth curved surface, the first curved surface, the second curved surface and the fifth curved surface are rotationally symmetrical free curved surfaces, the third curved surface is a rotational paired paraboloid, and a focal point of the paraboloid is a virtual light point of reflected ray of the second curved surface, and the fourth curved surface is a cylindrical surface and used for connecting the third curved surface and the fifth curved surface. The free curved-surface reflector is composed of three curved surfaces. By the arrangement, optional viewing angles can be lit, and lighting effect of the optical system cannot be lowered due to total reflection.

The invention provides a wide color gamut backlight source for display of LED combined with perovskite quantum dot glass-ceramics, and is used for providing a light source for the displayer. The backlight source comprises the LED and the perovskite quantum dot glass-ceramics. The perovskite quantum dot glass-ceramics comprises red light, green light and blue light perovskite quantum dot glass-ceramics. The perovskite quantum dot glass-ceramics material is CsPbX3 (X=Cl, Br, I) or CsPb (ClxBr1-x) 3 or CsPb (BrxI1-x) 3. The backlight source spectrum contains its own blue light component of the blue LED, the narrow linewidth green light component produced by exciting CsPbBr3 or CsPb (BrxI1-x) 3 quantum dot glass-ceramics by the blue LED and the narrow linewidth red light component produced byexciting CsPbI3 or CsPb (BrxI1-x) 3 quantum dot glass-ceramics by the blue LED. The backlight source spectrum can also contain the narrow linewidth blue light component produced by exciting the blue light CsPb (ClxBr1-x)3 quantum dot glass-ceramics by the short wavelength LED of which the wavelength is less than the absorption cutoff wavelength of the quantum dot, the narrow linewidth green lightcomponent produced by exciting the CsPbBr3 or CsPb (ClxBr1-x)3 quantum dot glass-ceramics by the short wavelength or blue LED and the narrow linewidth red light component produced by exciting the CsPbI3 or CsPb (ClxBr1-x)3 quantum dot glass-ceramics by the short wavelength or blue LED.

The invention relates to an aluminate green phosphor doped with rare earth elements gallium and bismuth, and a preparation method of the aluminate green phosphor. The aluminate green phosphor is activated by use of Ce<3+>, and the general formula of the aluminate green phosphor is Y3-x-nBinAl5-yGayO12: Ce<3+>x, wherein the numeric range of x is from 0.01 to 0.2, and preferably from 0.06 to 0.08; the numeric range of y is from 0.5 to 4.5, and preferably from 1.0 to 4.5; the numeric range of n is from 0 to 0.006, and preferably from 0.002 to 0.006. The phosphor having the main emission peak in the green position is obtained by doping YAG (Yttrium Aluminum Garnet) phosphor with the element Ga, and the overall luminous efficacy of the phosphor is not reduced; the green phosphor is matched with yellow phosphor and a blue LED (Light Emitting Diode) chip so that a high-brightness white-light LED can be obtained; if the green phosphor is matched with the blue LED chip, green light can be obtained directly; if the green phosphor is matched with the yellow phosphor and the blue LED chip, cold-tone white light can be obtained; the green phosphor also can be matched with red phosphor and the blue LED chip to obtain white light; and besides, trace bismuth element also can be added to the aluminate green phosphor, so that the luminous intensity of the prepared phosphor can be greatly improved.

The invention is applicable to the field of illumination and provides a constant current driving circuit, an LED light source and a locomotive light. The circuit comprises a BOOST circuit, an isolating DC/DC constant current driving circuit, an under-voltage control circuit, a low-voltage switching control circuit and a control power supply circuit, can support direct current input with low voltage and wide range, can effectively solve the defects of narrow input voltage range, short service life of the light source, low light efficiency, poor vibration resistance, short maintenance cycle, insufficient protection functions and the like of a locomotive light used in a coal mine, and improves safety of mine operation.

The invention discloses a composite cover plate. The composite cover plate comprises a cover plate body, a fixed ring, a first light transmitting part and a second light transmitting part; a first through hole is formed in the cover plate body; the fixed ring is at least partially contained in the first through hole and contacts and covers the inner wall of the first through hole; the first light transmitting part is at least partially contained in the fixed ring and is provided with a first light-entering surface which is a convex curved surface; light emitted by a flashlight enters the first light transmitting part from the first light-entering surface; the second light transmitting part is contained in the fixed ring; the light emitted by the flashlight after penetrating the first light transmitting part penetrates the second light transmitting part and is emitted out. The invention also discloses a camera module and a mobile terminal. The shooting effect and the reality of the shot pictures and video pictures of the camera module are improved, and the user experience is improved.

The invention relates to an intelligent traffic LED (Light-Emitting Diode) flash lamp and a circuit thereof, aiming to solve the problems that the existing flash lamp causes potential safety hazards to drivers owing to having certain light pollution and that the illumination range of the existing flash lamp has certain limitations. The intelligent traffic LED flash lamp is characterized in that: heat-conducting silicone grease is applied between an aluminum substrate and an LED lamp; the heat-conducting silicone grease is also applied between the aluminum substrate and a lampshade; a radiating fin is formed on the rear portion of the lampshade; a heat-dissipation cavity is formed in the lampshade on the lower portion of the aluminum substrate; a power cord and a respirator are arranged within the heat-dissipation cavity; and symmetrical vent holes are formed on the cavity walls on both sides of the heat-dissipation cavity. The intelligent traffic LED flash lamp effectively solves the problem of light pollution by employing the technology from faint light or medium light to instantaneous shining. The flash lamp is provided with the structure having the external radiating fin and the internal respirator, so that the heat dissipation performance is effectively improved and the illumination range is wide.

The present invention provides an electroluminescent device, a manufacturing method and driving method thereof, and a display device. The electroluminescent device comprises a transparent substrate, and a first light emitting unit and a second light emitting unit disposed at both sides of the transparent substrate respectively, wherein the first light emitting unit and the second light emitting unit have the same light output direction and are connected to two control circuit respectively. In the present invention, a parallel device structure is adopted to achieve independent control of two light emitting units in a single electroluminescent device, not only the color temperature is adjustable, but also the light emitting efficiency of the device can be increased. Also the transparent substrate can be fabricated using polymers having a refractive index adapted to the light emitting material, thereby reducing the optical waveguide loss in the device and realizing display of flexible device.

The invention discloses a cover plate, an organic light-emitting display panel and a display device. Specifically, the present invention provides the cover plate for the organic light emitting displaydevice, and the cover plate comprises a substrate having a plurality of light emitting units defined by a light shielding structure and having a light incident surface and a light emitting surface, wherein a color conversion layer is arranged in at least part of the light emitting units and is arranged on the light incident surface of the substrate; a light modulation layer which is arranged at the side, away from the substrate, of the color conversion layer, and is configured to enable incident light to penetrate through the color conversion layer and the substrate and to be emitted out fromthe light emitting surface of the substrate. Therefore, the light modulation layer can adjust the light emitting direction of the incident light, the incident light can be emitted from the light emitting surface, the light emitting efficiency of the organic light emitting display panel can be improved, the power consumption can be reduced, and the display quality can be improved.