Seoul Semiconductor Co., Ltd.

Seoul Opto Device Co., Ltd.

Seoul Viosys Co., Ltd.

Posco

Hong San Kim

Chung Hoon Lee

James Stephen Speck

Jae Ho Lee

Sung Han Kim

Jae Jo Kim

Dae Won Kim

Keon Young Lee

Hyuck Jung Choi

Hyuok Jung Choi

Woo Il Park

Min Young Cho

Sang Hyun Kim

Hyun Jong Kim

Moo Eob Choi

Seok In Park

Sang Ho Yi

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 &#xbd; 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 &#xbd; 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.

Light emitting device for AC power operation

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 &#xbd; 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 daring a &#xbd; 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.

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.

LED package having an array of light emitting cells coupled in series

Exemplary embodiments of the present invention disclose a light-emitting device including a first power source connection terminal and a second power source connection terminal, the first and second power source connection terminals configured to be connected to an external power source, and a plurality of light emitting cell arrays, each of the plurality of light emitting cell arrays being connected in parallel to one another between the first and the second power source connection terminals, each of the plurality of light emitting cell arrays comprising serially connected light emitting cells. Each of the light emitting cells includes a first conductivity-type semiconductor layer, a second conductivity-type semiconductor layer, an active layer disposed between the first conductivity-type semiconductor layer and the second conductivity-type semiconductor layer, and an electrode pad disposed on the second conductivity-type semiconductor layer.

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 &#xbd; 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.

Disclosed is a light emitting device having a plurality of light emitting cells. The light emitting device comprises a thermally conductive substrate, such as a SiC substrate, having a thermal conductivity higher than that of a sapphire substrate. The plurality of light emitting cells are connected in series on the thermally conductive substrate. Meanwhile, a semi-insulating buffer layer is interposed between the thermally conductive substrate and the light emitting cells. For example, the semi-insulating buffer layer may be formed of AlN or semi-insulating GaN. Since the thermally conductive substrate having a thermal conductivity higher than that of a sapphire substrate is employed, heat-dissipating performance can be enhanced as compared with a conventional sapphire substrate, thereby increasing the maximum light output of a light emitting device that is driven under a high voltage AC power source. In addition, since the semi-insulating buffer layer is employed, it is possible to prevent an increase in a leakage current through the thermally conductive substrate and between the light emitting cells.

Light emitting device having a plurality of light emitting cells and method of fabricating the same

Growing community of inventors

Seongnam-si, South Korea

Hong San Kim