• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.449-452
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• 2009

Ink-jet printed (IJP) self-aligned (SA) organic light emitting diodes (OLEDs) and its application to light emitting seal have investigated. Ink-jet printing of light emitting material is carried out onto transparent anode covered with insulating material. Laminated light emitting seal with SA IJP OLED without photo - lithographic process and any vacuum process, noncontact type electromagnetic power supply without electric power supply line, and light emitting tag with network type RF communication terminal by controlling display information were demonstrated.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.358-359
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• 2003

Organic light-emitting device have attracted much interest due to their potential application in large area, full color, flat panel displays. Poly(p-phenylene)(PPP), as a blue light-emitting materials, have studied in our previous report. Thus, we selected poly(p-phenylene) (PPP) to fabricate the organic light-emitting filaments(OLEF) [1-2]. In this paper, we fabricated an organic light-emitting filaments(OLEF), which can be woven into fabric. The key concept was flexibility in one-dimensional structures. (omitted)

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.779-780
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• 2009

New inverted architecture of a hybrid inorganic-organic light-emitting diode, utilizing ZrO2 electron-injecting layer, is presented. The thickness of the ZrO2, as well as the annealing of the light-emitting polymer, is found critical to obtain good performance. A range of light-emitting polymers is shown to operate efficiently in the proposed architecture.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.648-650
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• 2007

We demonstrate highly efficient White Polymer Electrophosphorescent Light-emitting Diode using newly developed green and red light emitting heteroleptic iridium complex, Ir-(pq)2tpy, and blue light emitting fluorescent dopant, BczVBi. The best luminous efficiency reached 28cd/A with maximum luminance of 87000cd/m2. The scheme for determining optimum device architecture and dopant concentrations were constructed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.606-609
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• 1999

We fabricated white light-emitting diode which have a mixed single emitting layer containing poly(N-vinylcarbazole), trois(8-hydroxyquinoline)aluminum and poly(3-hexylthiophene) and investigated the emission properties of it. It is possible to obtain a blue light from poly(N-vinylcarbazole). green light from tris(8-hydroxyquinoline)aluminum and red light from poly(3-hexylthiophene). The fabricated device emits white light with slight orange light. We think that the energy transfer in a mixed layer occurred from PVK to Alq₃ and P3HT resulted in decreasing the blue light intensity from PVK. We find that the efficiency of the white light electroluminescent device can be improved by injecting electron more effectively and blue light need to improve the color purity of white light.

• Journal of Applied Reliability
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• v.9 no.2
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• pp.131-148
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• 2009

An organic light emitting diode (OLED), also light emitting polymer (LEP) and organic electro luminescence (OEL), is any light emitting diode (LED) whose emissive electroluminescent layer is composed of a film of organic compounds. The layer usually contains a polymer substance that allows suitable organic compounds to be deposited. They are deposited in rows and columns onto a flat carrier by a simple "printing" process. The resulting matrix of pixels can emit light of different colors. Such systems can be used in television screens, computer displays, small, portable system screens such as cell phones and PDAs, advertising, information and indication. OLEDs can also be used in light sources for general space illumination, and large-area light-emitting elements. In this paper, we develop the general guide line of the accelerated life test for assuring B10 life of AMOLED(Active Matrix Organic Light Emitting Diode) and PMOLED(Passive Matrix Organic Light Emitting Diode) which are widely used for display monitor less than 115 mm.

• Journal of Information Display
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• v.9 no.2
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• pp.14-17
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• 2008

A charge trapping host structure was developed to improve the light-emitting efficiency of green phosphorescent organic light-emitting diodes. N, N'-dicarbazolyl-3,5-benzene(mCP) and a spirobifluorene based triplet host(PHl) were co-deposited as hosts in the emitting layer and the device performance was examined according to the composition mCP and PH1. The results showed that the quantum efficiency could be improved by 30 % using a mixed host of mCP and PH1.

• Journal of Biomedical Engineering Research
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• v.35 no.5
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• pp.125-131
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• 2014

The purpose of this study is to verify the utility of reflected photoplethysmography sensor using two green light emitting diodes that influenced by ambient light. Recently it has been studied that green light emitting diode is suitable for light source of reflected photoplethysmography sensor at low temperature and high temperature. Another study showed that, green light is better for monitoring heart rate during motion than led light. However, it has a bad characteristic about ambient light noise. To verify the utility of reflected photoplethysmography sensor using green light emitting diode, this study measures the photoplethysmography signal that is distorted by ambient light and will propose a solution. This study has two parts of research method. One is measurement system that composed sensor and board. The sensor is made up PE-foam and Non-woven fabric for flexible sensor. The photoplethysmography signal is measured by measurement board that composed high-pass filter, low-pass filter and amplifier. Ambient light source is light bulb and white light emitting diode that has three steps brightness. Photoplethysmography signal is measured with lead II electrocardiography signal at the same time and it is measured at the finger and radial artery for 1 minute, 1000 Hz sampling rate. The lead II electrocardiography signal is a standard signal for heart rate and photoplethysmography signal that measured at the finger is a standard signal for waveform. The test is repeated 3 times using three sensor. The data is processed by MATLAB to verify the utility by comparing the correlation coefficient score and heart rate. The photoplethysmography sensor using two green light emitting diodes is shown better utility than using one green light emitting diode and red light emitting diode at the ambient light. The waveform and heart rate that measured by two green light emitting diodes are more identical than others. The amount of electricity used is less than red light emitting diode and error peak detectability factor is the lowest.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.347-348
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• 2006

This paper performed the basic study for developing the Photodynamic Therapy Equipment for medical treatment. The equipment have been manufactured by using the High Bright Light Emitting Diode and TLC5941 integrated circuit. As a result, 630nm Light Emitting Diode Module was made for the optimization of irradiation condition. And we confirmed the current change according to increase of the level of Light Emitting Diode Module.

• Applied Science and Convergence Technology
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• v.25 no.1
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• pp.1-6
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• 2016

Quantum dots (QDs) are considered as excellent color conversion and self-emitting materials for display and lighting applications. In this article, various technologies which can be used to realize white light emission with QDs are discussed. QDs have good color purity with a narrow emission spectrum and tunable optical properties with size control capabilities. For white light emission with a color-conversion approach, QDs are combined with blue-emitting inorganic and organic light-emitting diodes (LED) to generate white emission with high energy conversion efficiency and a high color rendering index for various display and lighting applications. Various device structures for self-emitting white QD light-emitting diodes (QD-LED) are also reviewed. Various stacking and patterning technologies are discussed in relation to QD-LED devices.