Abstract:
This invention relates to luminescent materials for ultraviolet light or visible light excitation comprising copper-alkaline-earth dominated inorganic mixed crystals activated by rare earth elements. The luminescent material is composed of one or more than one compounds of silicate type and/or germinate or germanate-silicate type. Accordingly, the present invention is a very good possibility to substitute earth alkaline ions by copper for a shifting of the emission bands to longer or shorter wavelength, respectively. Luminescent compounds containing Copper with improved luminescent properties and also with improved stability against water, humidity as well as other polar solvents are provided. The present invention is to provide copper containing luminescent compounds, which has high correlated color temperature range from about 2,000K to 8,000K or 10,000K and CRI up to over 90.
Abstract:
The present invention relates to a light emitting device including a light emitting element having a plurality of light emitting cells arranged on a substrate, a first electrode arranged on each light emitting cell of the plurality of light emitting cells, a second electrode arranged between the substrate and each light emitting cell of the plurality of light emitting cells, the second electrode being disposed to face the first electrode. The light emitting device also includes a conductive material electrically connecting the second electrode arranged under a first light emitting cell of the plurality of light emitting cells to the first electrode arranged on an adjacent second light emitting cell of the plurality of light emitting cells, and a control unit configured to control waveforms of a voltage and a current applied to the light emitting element.
Abstract:
Disclosed is an improved light-emitting device for an AC power operation. An AC light-emitting device according to the present invention employs a variety of means by which light emission time is prolonged during a ½ cycle in response to a phase change of an AC power source and a flicker effect can be reduced. For example, the means may be switching blocks respectively connected to nodes between the light emitting cells, switching blocks connected to a plurality of arrays, or a delay phosphor. Further, there is provided an AC light-emitting device, wherein a plurality of arrays having the different numbers of light emitting cells are employed to increase light emission time and to reduce a flicker effect.
Abstract:
The present invention discloses a light emitting diode (LED) including a plurality of light emitting cells arranged on a substrate. The LED includes half-wave light emitting units each including at least one light emitting cell, each half-wave light emitting unit including first and second terminals respectively arranged at both ends thereof; and full-wave light emitting units each including at least one light emitting cell, each full-wave light emitting units including third and fourth terminals respectively formed at both ends thereof. The third terminal of each full-wave light emitting unit is electrically connected to the second terminals of two half-wave light emitting units, and the fourth terminal of each full-wave light emitting unit is electrically connected to the first terminals of other two half-wave light emitting units. Also, a first half-wave light emitting unit is connected in series between the third terminal of a first full-wave light emitting unit and the fourth terminal of a second full-wave light emitting units, and a second half-wave light emitting units is connected in series between the fourth terminal of the first full-wave light emitting unit and the third terminal of the second full-wave light emitting unit.
Abstract:
Disclosed is an improved light-emitting device for an AC power operation. A conventional light emitting device employs an AC light-emitting diode having arrays of light emitting cells connected in reverse parallel. The arrays in the prior art alternately repeat on/off in response to a phase change of an AC power source, resulting in short light emission time during a ½ cycle and the occurrence of a flicker effect. An AC light-emitting device according to the present invention employs a variety of means by which light emission time is prolonged during a ½ cycle in response to a phase change of an AC power source and a flicker effect can be reduced. For example, the means may be switching blocks respectively connected to nodes between the light emitting cells, switching blocks connected to a plurality of arrays, or a delay phosphor. Further, there is provided an AC light-emitting device, wherein a plurality of arrays having the different numbers of light emitting cells are employed to increase light emission time and to reduce a flicker effect.
Abstract:
Disclosed are non stoichiometric Copper Alkaline Earth Silicate phosphors activated by divalent europium for using them as high temperature stable luminescent materials for ultraviolet or daylight excitation. The phosphors are represented as the formula (BauSryCawCux)3−y(Zn,Mg,Mn)zSi1+bO5+2b:Eua. The nonstoichiometric tetragonal silicate is prepared in a high temperature solid state reaction with a surplus of silica in the starting mixture. Furthermore, luminescent tetragonal Copper Alkaline Earth Silicates are provided for LED applications, which have a high color temperature range from about 2,000K to 8,000K or 10,000K showing a CRI with Ra=80˜95, when mixed with other luminescent materials.
Abstract:
A light emitting device includes a plurality of light emitting cells which are formed on a substrate and each of which has an N-type semiconductor layer and a P-type semiconductor layer located on a portion of the N-type semiconductor layer. The plurality of light emitting cells are bonded to a submount substrate. Heat generated from the light emitting cells can be easily dissipated, so that a thermal load on the light emitting device can be reduced. Since the plurality of light emitting cells are electrically connected using connection electrodes or electrode layers formed on the submount substrate, it is possible to provide light emitting cell arrays connected to each other in series. Further, it is possible to provide a light emitting device capable of being directly driven by an AC power source by connecting the serially connected light emitting cell arrays in reverse parallel to each other.
Abstract:
The present invention relates to a light emitting element with arrayed cells, a method of manufacturing the same, and a light emitting device using the same. The present invention provides a light emitting element including a light emitting cell block with a plurality of light emitting cells connected in series or parallel on a single substrate, and a method of manufacturing the same, wherein each of the plurality of light emitting cells includes an N-type semiconductor layer and a P-type semiconductor layer, and the N-type semiconductor layer of one light emitting cell is electrically connected to the P-type semiconductor layer of another adjacent light emitting cell. Further, the present invention provides a light emitting device including a light emitting element with a plurality of light emitting cells connected in series. Accordingly, it is possible to simplify a manufacturing process of a light emitting device for illumination capable of being used with a household AC power source, to decrease a fraction defective occurring in manufacturing a light emitting device for illumination, and to mass-produce the light emitting device for illumination. Further, there is an advantage in that DC driving efficiency can be enhanced in an AC operation by installing a predetermined rectifying circuit outside the light emitting element.
Abstract:
Disclosed is a light emitting diode (LED) package having an array of light emitting cells coupled in series. The LED package comprises a package body and an LED chip mounted on the package body. The LED chip has an array of light emitting cells coupled in series. Since the LED chip having the array of light emitting cells coupled in series is mounted on the LED package, it can be driven directly using an AC power source.
Abstract:
Exemplary embodiments of the present invention relate to light emitting devices including strontium oxyorthosilicate-type phosphors. The light emitting device includes a light emitting diode, which emits light in the UV or visible range, and phosphors disposed around the light emitting diode to absorb light emitted from the light emitting diode and emit light having a different wavelength from the absorbed light. The phosphors include an oxyorthosilicate phosphor having a general formula of Sr3-x-y-zCaxMIIySiO5: Euz with a calcium molar fraction in the range of 0