• Journal of Information Display
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• v.6 no.2
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• pp.12-15
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• 2005

We propose a new pixel design for active matrix organic light emitting diode (AM-OLED) displays using hydrogenated amorphous silicon thin-film transistors (a-Si:H TFTs). The pixel circuit is composed of five TFTs and one capacitor, and employs only one additional control signal line. It is verified by SPICE simulation results that the proposed pixel compensates the threshold voltage shift of the a-Si:H TFTs and OLED.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.413-418
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• 2006

Highly stable thin-film transistor (TFT) pixel employing both low temperature polycrystalline silicon (LTPS) and amorphous silicon (a-Si) for active matrix organic light emitting diode (AMOLED) is discussed. ELA (excimer laser annealing) LTPS-TFT pixel should compensate $I_{OLED}$ variation caused by the non-uniformity of LTPS-TFT due to the fluctuation of excimer laser energy and amorphous silicon TFT pixel is desired to suppress the decrease of $I_{OLED}$ induced by the degradation of a-Si TFT. We discuss various compensation schemes of both LTPS and a-Si TFT employing the voltage and the current programming.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1297-1300
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• 2005

We propose a new pixel design for active matrix organic light emitting diode (AM-OLED) displays using hydrogenated amorphous silicon thin-film transistors (a-Si:H TFTs). The pixel circuit is composed of five TFTs and one capacitor, and employs only one additional control signal line. It is verified by SPICE simulation results that the proposed pixel compensates the threshold voltage shift of the a-Si:H TFTs and OLED.

• 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 the Korea Academia-Industrial cooperation Society
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• v.5 no.6
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• pp.495-498
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• 2004

Now days, people live in information age, thus, we are required methods to use and apply information to our lives more effective. There is a lot of research going on weight, size, and power consumption to provide high quality display close to full color. In this paper, I‘ll discuss the methods of precise and the need of improvements of driving circuit, to apply driving circuit to digital circuit of OLED(Organic Light-Emitting Diode), which satisfies all functions mentioned above.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.793-796
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• 2005

A structure and a design of device were developed to fabricate large-scale active matrix organic light-emitting diode (AMOLED) display with good color purity and high aperture ratio. With these technologies, we developed a full color 14.1 inch WXGA AMOLED display. For the integration of OLED on an active matrix a-Si TFT backplane, an efficient top emission OLED is essential since the TFT circuitry covers a large position of the pixel aperture. These technologies will enable up the OLED applications to larger size displays such as desktop monitors and TVs.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.6
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• pp.523-529
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• 2008

In this paper, we proposed mobile LCD module test device on embedded based, when operating the existing LCD, divide flicker clearly in full frame, and configuration so as to support between other CPU interface, MDDI, SPI, 24Bit RGB interface, etc. that is based on a high-speed CPU. In addition, when demand to test about each pixel of LCD, it is possible to change IP design of H/W, FPGA, but proposed system is application possible without other design changing. Proposed system is made smaller and equipped with battery, so secure with mobility for effective test the LCD/OLED module and it is able to test the pattern by the client program, for example exiting picture, mpeg, simple pattern test and test per pixel, scale, rotation, Odd/Even pixel per video, etc. From now on, if integrating with independent test system and it is configured that is able to mutual communication and test, it is expected to reduce consumption of human resources and improve productivity for LCD module test.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.6 s.348
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• pp.1-8
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• 2006

In this paper, we designed a pixel circuit for AMOLED display based on organic thin film transistors and analyzed the operation with SPICE simulation. First, we theoretically designed the pixel circuit with the result of layout for fabricating $32\times32$ AMOLED panel, TFT W/L and capacitance of storage capacitor. And we simulated the designed pixel circuit using HSPICE for analyzing electrical performance. As a result of simulation, we identified the possibility of AMOLED display based on OTFTs.

• Journal of the Semiconductor & Display Technology
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• v.21 no.1
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• pp.50-55
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• 2022

Due to the wavelength shift problem of micro LED caused by the change of current density, the active matrix driving pixel circuit that is used in OLED cannot be applied to micro LED displays. Therefore, we need a gray scale method based on modulation of duration time of light emission. In this study, we propose the PWM-controlled micro LED pixel circuit based on CMOS thin film transistors (TFTs). By adopting CMOS inverter structure, we can reduce the number of storage capacitors from the circuit and make the operating speed of the circuit faster. Most of all, our circuit is designed to make operating speed of PWM circuit faster by adopting feedback effect through double gate TFT structure. As a result, it takes about 4.7ns to turn on the LED and about 5.6ns to turn it off. This operating time is short enough to avoid the color distortion and help the precise control of the gray scale.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.1149-1152
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• 2003

Now a days, many different kinds of display technologies such as Liquid Crystal Display (LCD), Organic Light Emitting Diode (OLED), and Liquid Crystal On Silicon (LCOS) are designed. And these display technologies will be used in many application products like High Definition Televisions (HDTVs) or mobile devices. In this paper, pattern generation circuit for display test is proposed. The proposed circuit will be embedded in the control circuit of display chip. Two differenct kinds of patterns is generated by the circuit. One is block pattern for color test, and the other is line pattern for pixel test. The shape of test pattern is determined by the values of registers in pattern generation circuit. The circuit is designed using Verilog HDL RTL code.