摘要:
The present invention relates to light-emitting diodes. A light-emitting diode according to an exemplary embodiment of the present invention includes a first group including a plurality of first light emitting cells connected in parallel to each other, and a second group including a plurality of second light emitting cells connected in parallel to each other. Each first light emitting cell and second light emitting cell has a semiconductor stack that includes a first conductivity-type semiconductor layer, a second conductivity-type semiconductor layer, and an active layer disposed between the first conductivity-type semiconductor layer and the second conductivity-type semiconductor layer. At least two light emitting cells of the first light emitting cells share the first conductivity-type semiconductor layer, and at least two light emitting cells of the second light emitting cells share the first conductivity-type semiconductor layer. The first light emitting cells are connected in series to the second light emitting cells.
摘要:
Exemplary embodiments of the present invention disclose a light emitting diode chip including a substrate having a first surface and a second surface, a light emitting structure arranged on the first surface of the substrate and including an active layer arranged between a first conductive-type semiconductor layer and a second conductive-type semiconductor layer, a distributed Bragg reflector arranged on the second surface of the substrate, the distributed Bragg reflector to reflect light emitted from the light emitting structure, and a metal layer arranged on the distributed Bragg reflector, wherein the distributed Bragg reflector has a reflectivity of at least 90% for light of a first wavelength in a blue wavelength range, light of a second wavelength in a green wavelength range, and light of a third wavelength in a red wavelength range.
摘要:
Exemplary embodiments of the present invention disclose a light emitting diode (LED) and a method of fabricating the same. The LED includes a substrate, a semiconductor stack arranged on the substrate, the semiconductor stack including an upper semiconductor layer having a first conductivity type, an active layer, and a lower semiconductor layer having a second conductivity type, isolation trenches separating the semiconductor stack into a plurality of regions, connectors disposed between the substrate and the semiconductor stack, the connectors electrically connecting the plurality of regions to one another, and a distributed Bragg reflector (DBR) having a multi-layered structure, the DBR disposed between the semiconductor stack and the connectors. The connectors are electrically connected to the semiconductor stack through the DBR, and portions of the DBR are disposed between the isolation trenches and the connectors.
摘要:
Exemplary embodiments of the present invention disclose a light emitting diode (LED) and a method of fabricating the same. The LED includes a substrate, a semiconductor stack arranged on the substrate, the semiconductor stack including an upper semiconductor layer having a first conductivity type, an active layer, and a lower semiconductor layer having a second conductivity type, isolation trenches separating the semiconductor stack into a plurality of regions, connectors disposed between the substrate and the semiconductor stack, the connectors electrically connecting the plurality of regions to one another, and a distributed Bragg reflector (DBR) having a multi-layered structure, the DBR disposed between the semiconductor stack and the connectors. The connectors are electrically connected to the semiconductor stack through the DBR, and portions of the DBR are disposed between the isolation trenches and the connectors.
摘要:
Exemplary embodiments of the present invention provide light emitting diode (LED) chips and a method of fabricating the same. An LED chip according to an exemplary embodiment includes a substrate; a light emitting structure arranged on the substrate, and an alternating lamination bottom structure arranged under the substrate. The alternating lamination bottom structure includes a plurality of dielectric pairs, each of the dielectric pairs including a first material layer having a first refractive index and a second material layer having a second refractive index, the first refractive index being greater than the second refractive index.
摘要:
An exemplary embodiment of the present invention discloses a light emitting diode chip including a substrate, a light emitting structure arranged on the substrate, the light emitting structure including an active layer arranged between a first conductive-type semiconductor layer and a second conductive-type semiconductor layer, and a distributed Bragg reflector to reflect light emitted from the light emitting structure. The distributed Bragg reflector has a reflectivity of at least 90% for light of a first wavelength in a blue wavelength range, light of a second wavelength in a green wavelength range, and light of a third wavelength in a red wavelength range.
摘要:
A light emitting diode (LED) chip for high voltage operation and an LED package including the same are disclosed. The LED chip includes a substrate, a first array formed on the substrate and including n light emitting cells connected in series, and a second array formed on the substrate and including m (m≦n) light emitting cells connected in series. During operation of the LED chip, the first array and the second array are operated by being connected in reverse parallel to each other. Further, when a driving voltage of the first array is delined as Vd1 and a driving voltage of the second array is defined as Vd2, a difference between Vd1 and Vd2×(n/m) is not more than 2V.
摘要:
A light emitting diode (LED) chip for high voltage operation and an LED package including the same arc disclosed. The LED chip includes a substrate, a first array formed on the substrate and including n light emitting cells connected in series, and a second array formed on the substrate and including m (m≦n) light emitting cells connected in series. During operation of the LED chip, the first array and the second array are operated by being connected in reverse parallel to each other. Further, when a driving voltage of the first array is delined as Vd1 and a driving voltage of the second array is defined as Vd2, a difference between Vd1 and Vd2×(n/m) is not more than 2V.
摘要:
A high-efficiency light emitting diode including: a semiconductor stack positioned on a support substrate, including a p-type compound semiconductor layer, an active layer, and an n-type compound semiconductor layer; an insulating layer disposed in an opening that divides the p-type compound semiconductor layer and active layer; a transparent electrode layer disposed on the insulating layer and the p-type compound semiconductor layer; a reflective insulating layer covering the transparent electrode layer, to reflect light from the active layer away from the support substrate; a p-electrode covering the reflective insulating layer; and an n-electrode is formed on top of the n-type compound semiconductor layer. The p-electrode is electrically connected to the transparent electrode layer through the insulating layer.
摘要:
A static excitation system that can eliminate shaft vibrations of a generator and overvoltage when it is underexited is provided. The static excitation system includes an initial excitation equipment; a step-down transformer; a 3-phase diode bridge; a boost chopper provided with a transistor and a resister, and maintaining DC voltage to be constant; a DC chopper provided with a plurality of transistors and diodes, and supplying DC power to a rotor of a generator; a boost controller for controlling the boost chopper; and a DC chopper controller for controlling the DC chopper, wherein, overvoltage applied on the excitation system when underexcited is eliminated owing to the boost chopper preventing any changes at an output terminal of the generator from being transferred to the excitation system, and maintaining the excitation DC voltage to be constant; and also owing to the DC chopper which is capable of 4 quadrant operation, hereby pole slipping of the generator can be prevented.