Electronics and Telecommunications Research Institute

Joon Tae Ahn

Kyong Hon Kim

Bong Je Park

Hye Yong Chu

Jeong Ik Lee

Jaehyun Moon

Jun-Han Han

Hak Kyu Lee

Hong Seok Seo

Jong Moo Lee

Min Yong Jeon

Dong Sung Lim

Woon Jin Chung

Byoung Gon Yu

Doo-Hee Cho

Nam Sung Cho

Jong Tae Lim

Seung Koo Park

Jin Wook Shin

Chul Woong Joo

Hong-Seok Seo

Jin Huh

Jonghee Lee

Joo Hyun Hwang

Sun Tak Park

El Hang Lee

Ho Young Kim

Myung Hyun Lee

Doo Hee Cho

Jae-Sik Sim

Minhyup Song

Sungil Kim

Yong Gyu Choi

Do Il Chang

Jung Min Park

Minje Song

Chi-Sun Hwang

Jae Bon Koo

Myung Lae Lee

Yongsoon Baek

Suntak Park

Hojun Ryu

Jung Jin Ju

Ji-Young Oh

Yong Soon Baek

Dae Kon Oh

Kyong-Hon Kim

Jung-Ho Song

Min-Yong Jeon

Hack Kyu Lee

Boong Joon Lee

Bong Joon Lee

An embodiment of the inventive concept includes an optical signal generating circuit, a controlling circuit, a waveform shaping circuit, and an output circuit. The optical signal generating circuit generates a first optical signal including pulses. The controlling circuit generates a control signal indicating a first pulse to be attenuated in magnitude among the pulses. The waveform shaping circuit attenuates a magnitude of the first pulse based on the control signal and the first optical signal, and generates a second optical signal including pulses corresponding to the pulses included in the first optical signal and the first pulse having the attenuated magnitude. The output circuit outputs an electric signal of bands corresponding to differences between frequencies of the pulses included in the second optical signal based on the second optical signal. A band corresponding to the first pulse among the bands of the electric signal is adjusted as the magnitude of the first pulse is attenuated.

Waveform generator

A radio frequency signal generation device may include an optical comb generator configured to generate an optical comb signal including a plurality of first wavelength signals having different wavelengths; a pulse shaper configured to attenuate remaining wavelength signals excluding a plurality of second wavelength signals among the plurality of first wavelength signals; an optical-electronic converter configured to generate a radio frequency signal including a carrier frequency signal from the plurality of second wavelength signals outputted from the pulse shaper; and a pulse shaping controller configured to control the pulse shaper such that a carrier frequency of the carrier frequency signal varies according to a frequency hopping pattern.

Radio frequency signal generation device, and transmitter and receiver including the same

Provided is a method of forming a film having a surface structure of a random wrinkles. A compound according to the present invention is coated and then, a film having a surface structure of random wrinkles may be simply formed through simple ultraviolet (UV) curing or thermosetting. When the film thus formed is used in an organic light emitting device, light generated from the organic light emitting device is scattered on surfaces of the random wrinkles to prevent light guide or total reflection, and thus, light is extracted to the outside. That is, a random structure disposed at the outside of the device performs a light extraction function and consequently, light efficiency of the organic light emitting device may be increased.

Method of forming a film having a surface structure of random wrinkles

Provided is a method of manufacturing an organic light-emitting device including a graphene layer. The method of manufacturing an organic light-emitting device according to the present invention may include providing a graphene donor unit including a patterned graphene layer, providing a device unit, and attaching the graphene layer of the graphene donor unit to an organic part. The device unit may include a substrate, a lower electrode, and the organic part which are sequentially stacked, and the organic part may include a dopant. The graphene donor unit may include the graphene layer, a release layer, and an elastic stamp layer which are sequentially stacked.

Methods of manufacturing organic light-emitting device

A dual-mode display including a substrate and a multiple sub-pixels on the substrate, in which each sub-pixel includes, a color selection reflector, and an optical shutter disposed on the color selection reflector, and an emissive devised disposed on the shutter, wherein the emissive device includes a cathode and an anode, and the cathode and the anode include a carbon-based material including graphene sheets, graphene flakes, and graphene platelets, and a binary or ternary transparent conductive oxide including indium oxide, tin oxide, and zinc oxide.

Dual-mode pixels including emissive and reflective devices, and dual-mode display using the pixels

A dual-mode display including a substrate and a plurality of sub-pixels on the substrate, in which each sub-pixel includes, a reflective device having an optical filter function which reflects different color according to electrical signals applied from outside the display, and an emissive device disposed on the reflective device, wherein the emissive device includes a cathode and an anode, and the cathode and the anode include a carbon-based material including graphene sheets, graphene flakes, and graphene platelets, and a binary or ternary transparent conductive oxide including indium oxide, tin oxide, and zinc oxide.

Provided is a dual-mode display including a substrate and a plurality of sub-pixels on the substrate, in which each sub-pixel includes an emissive device, a color selection reflector disposed on one side of the emissive device, and an optical shutter disposed on another side of the emissive device, wherein the emissive device includes a cathode and an anode, and the cathode and the anode include a carbon-based material including graphene sheets, graphene flakes, and graphene platelets, and a binary or ternary transparent conductive oxide including indium oxide, tin oxide, and zinc oxide.

Provided is a dual-mode display including a substrate, and a plurality of sub pixels on the substrate. Each of the sub pixels may include an emissive device, a reflective optical filter provided on a surface of the emissive device, and an optical shutter provided on other surface of the emissive device.

Dual-mode pixel including emissive and reflective devices and dual-mode display with the same

Provided is a hybrid light emitting device. The hybrid light emitting device may include the first light emitting part on the substrate, the capping layer, and the second light emitting part. The first light emitting part may emit light having a first wavelength, and the first light emitting part may include a first electrode, an organic emitting layer, and a second electrode sequentially disposed. A second light emitting part may generate light having a second wavelength. A capping layer may be disposed between the organic emitting layer and the second light emitting part. The capping layer may reflect light having the first wavelength and transmit light having the second wavelength.

Hybrid light emitting device having a capping layer

The inventive concept provides optic couplers, optical fiber laser devices, and active optical modules using the same. The optic coupler may include a first optical fiber having a first core and a first cladding surrounding the first core, a second optical fiber having a second core transmitting a signal light to the first optical fiber and a third cladding surrounding the second core, third optical fibers transmitting pump-light to the first optical fiber in a direction parallel to the second optical fiber; and a connector connected between the first optical fiber and the second optical fiber, the connector extending the third optical fibers disposed around the second optical fiber toward the first optical fiber, the connector comprising a third core connected between the first core and the second core and a fifth cladding surrounding the third core.

Optic coupler, optical fiber laser device, and active optical module using the same

Provided is a method of fabricating an organic light emitting device that may form a light scattering layer having an irregular random structure at a low temperature. The method includes providing a substrate coated with a precursor layer; sequentially forming a metal layer and an organic layer on the precursor layer; performing a heat treatment of the organic layer to form an organic mask from the organic layer; patterning the metal layer by using the organic mask to form a metal mask; patterning the precursor layer by using the metal mask to form a light scattering layer having an irregular random structure; removing the metal mask and the organic mask; and sequentially stacking a planarization layer, a first electrode, an organic light emitting layer, a second electrode, and a passivation layer on the light scattering layer.

Method of fabricating organic light emitting device

There are provided an optical fiber coupler configured to improve or optimize optical efficiency and coupling efficiency, a method of manufacturing the optical fiber coupler, and an active optical module. The optical fiber coupler includes a first optical fiber and second optical fibers. The first optical fiber includes a first core and a first cladding surrounding the first core, and the second optical fibers are coupled to the first cladding. The first cladding includes a first coupling facet to which ends of the second optical fibers are coupled.

Optical fiber coupler, method of manufacturing the optical fiber coupler, and active optical module

Provided is a double clad fiber device. The double clad fiber device includes a double clad fiber, a pump combiner, at least one first laser diode, and at least one second laser diode. The double clad fiber includes a core and a clad. The pump combiner provides pump light to the core and the clad through one end of the double clad fiber, respectively. The at least one first laser diode provides first pump light to the clad through the pump combiner. The at least one second laser diode provides second pump light to the core through the pump combiner.

Double clad fiber laser device

Provided is a gain-clamped (GC) optical amplifier using a fiber Raman amplifier (FRA) having a Raman cavity. The FRA having a Raman cavity comprises a Raman fiber module (RFM) amplifying and outputting an input optical signal and a resonant cavity generating a Raman laser and a gain clamping laser (GC laser), wherein the resonant cavity is formed as a feedback loop between an input terminal and an output terminal of the RFM. Accordingly, a gain of an optical signal propagating along a core of RFM keeps a constant value regardless of input signal intensity by generating the GC laser for gain clamping between a wavelength band of the Raman laser and a gain band of input signals.

Gain-clamped optical amplifying apparatus using fiber Raman amplifier having Raman cavity

A light coupler emitting a high power laser with a high beam quality and a fiber laser system including the light coupler is disclosed. The light coupler includes a first optical fiber bundle comprising a plurality of first optical fibers having either a single-mode core or a few-mode core and a second optical fiber, which guides multi-mode beams and is connected to the first optical fiber bundle. The optical fiber laser system includes a light coupler having a first optical fiber bundle comprising a plurality of first optical fiber having either a single-mode core or a few-mode core and a second optical fiber, which is connected to the first optical fiber bundle, is either a single cladding optical fiber or a double cladding optical fiber, and guides multi-mode beams, and one or more gain medium optical fiber, which is connected to the light coupler and emits light.

Light coupler and fiber laser system including the same

Growing community of inventors

Daejeon, South Korea

Joon Tae Ahn