• 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.

• Proceedings of the IEEK Conference
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• 2002.06b
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• pp.257-260
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• 2002

This paper describes the pixel of AMOLED(act ive matrix organic light emitting diode) driving circuit by poly-sl technology. The area per pixel is 278um$\times$278um in 120$\times$160(2.2 inch) Driving the OLEDS with active matrix leads to the lower voltage operation, the lower peak pixel currents and the display with much greater efficiency and brightness The role of the active matrix is to provide a constant current throughout the entire frame time and is eliminating the high currents encountered In the passive matrix approach, This design can support the high resolutions expected by the consumer because the current variation specification is norestricted. The pixel has been designed driving TFT threshold voltage cancellation circuit and wide aperture ratio circuit that communizes 4 pixel. The test simulation results and layout are 11% per threshold-current var Eat ion and 12.5% the aperture ratio of increase.

• ETRI Journal
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• v.26 no.5
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• pp.509-511
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• 2004

This paper describes a novel current driving circuit for an active matrix organic light emitting diode (AMOLED). The proposed current driving circuit has a lower power consumption and higher chip density for the AMOLED display compared with the conventional one because all elements operate at a normal voltage and are shielded from the high voltage of the panel. The chip size and power consumption of the current driving circuit for an AMOLED can be improved by about 30 to 40% and 10 to 20%, respectively, compared with the conventional one.

• Information Display
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• v.15 no.2
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• pp.16-24
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• 2014

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.881-884
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• 2003

We propose a new pixel structure for Active Matrix OLED (AMOLED). The proposed pixel structure can display full color images by compensating threshold voltage (Vth) variation of driving TFTs. And we obtain an improved contrast ratio(C/R) of higher than 600:1

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.799-802
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• 2005

This paper described a 2.2" $QCIF^+$ ($176{\times}RGB{\times}220$) active matrix organic light-emitting diode display (AMOLED) using low-temperature poly-silicon (LTPS) technology. We have designed the OLED pixel to match the OLED material characteristic with COG specification and optimized pixel structure to improve color gamma adjustment and simplify signal complexity.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.529-530
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• 2005

A voltage driving AMOLED(Active Matrix Organic Light Emitting Diode) is useful for large-sized, high resolution OLED display. The conventional 2-TFTs, 1-CAP AMOLED circuit suffer from the threshold voltage variation of TFT. In this paper, a new AMOLED structure is proposed. It is composed of 5-TFTs and 2-capacitors. It is described that the operating principle and the characteristics of the proposed structure and is verified the performance by HSPICE simulation. The result of simulation shows that the effect of the threshold voltage variation in this circuit, is able to neglect.

• Journal of Information Display
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• v.7 no.4
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• pp.21-23
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• 2006

We developed a 4.5" 192${\times}$64 active matrix organic light-emitting diode display on a glass using organic thin-film transistor (OTFT) switching-arrays with two transistors and a capacitor in each sub-pixel. The OTFTs has bottom contact structure with a unique gate insulator and pentacene for the active layer. The width and length of the switching OTFT is 800${\mu}m$ and lO${\mu}m$ respectively and the driving OTFT has 1200${\mu}m$ channel width with the same channel length. On/off ratio, mobility, on-current of switching OTFT and on-current of driving OTFT were $10^6,0.3{\sim}0.5$ $cm^2$/V·sec, order of 10 ${\mu}A$ and over 100 ${\mu}A$, respectively. AMOLEDs composed of the OTFT switching arrays and OLEDs made using vacuum deposition method were fabricated and driven to make moving images, successfully.

• Journal of the Korea Safety Management & Science
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• v.12 no.4
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• pp.61-66
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• 2010

Organic light emitting diode(OLED) has been developed fast from 1963 when electric light emitting phenomenon was discovered. PMOLED(passive matrix OLED) is producted earlier than AMOLED(active matrix OLED). PMOLED is mainly mounted at sub display, but AMOLED is mounted at main display. Nowadays AMOLED is expanded to PMP(portable multimedia players), navigation and TV market. Even thought OLED's market is opening to many applications, OLED's life is worried until now. If we know about OLED's real life, we need time to test so much time over 20,000hrs. Realistically, there is difficult to test such as long time with products from the information-technology sector having a short life cycle. In this paper, we study about OLED's accelerated test to reduce life test by current. We can design OLED's accelerated life model by the result of test. The model consists of design variables like ratio of light emitting, organic material structure, condition of aging, etc. In conclusion, this model can be applied to study about organic material, machine and manufacturing process etc, and also it's possible to develop a method of manufacturing process & materials, so we need to study on the subject of this paper continuously.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.108-112
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• 2002

A new pixel driving method for organic light-emitting diode (OLED) flat-panel display (FPD) is proposed. The new charge-pump passive-matrix pixel driver consists only of a storage capacitance and a rectifying diode, and no thin-film transistor (TFT) is needed. The new driver not only supplies a constant current to the OLED throughout the whole period of panel scanning like an active-matrix driver, but also provides a highly linear gray-scale control through a pure digital manner.