• Journal of Information Display
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• v.7 no.1
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• pp.35-40
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• 2006

Organic light-emitting diode (OLED) display panel using the charge-pump (CP) pixel addressing scheme was fabricated, and the results show that it is applicable for information display. A CP-OLED panel with 64 ${\times}$ 64 pixels consisting of thin-film capacitors and amorphous silicon Schottky diodes was fabricated using conventional thin-film processes. The pixel drive circuit passes electrical current into the OLED cell during most of the frame period as in the thin-film transistor (TFT)-based active-matrix (AM) OLED displays. In this study, the panel was operated at a voltage level of below 4 V, and this operation voltage can be reduced by eliminating the overlap capacitance between the column bus line and the common electrode.

• Journal of the Optical Society of Korea
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• v.18 no.6
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• pp.777-782
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• 2014

This paper proposes an RGB to RGBY color conversion algorithm for liquid crystal display (LCD) using RGW pixel structure with two-field (yellow and blue) sequential driving method. The proposed algorithm preserves the hue and saturation of the original color by maintaining the RGB ratio, and it increases the luminance. The performance of the proposed RGBY conversion algorithm is verified using the MATLAB simulation with 24 images of Kodak lossless true color image suite. The simulation results of average color difference CIEDE2000 (${\delta}E^*_{00}$) and scaling factor are 0.99 and 1.89, respectively. These results indicate that the average brightness is increased 1.89 times compared to LCD using conventional RGB pixel structure, without increasing the power consumption and degrading the image quality.

• Electronics and Telecommunications Trends
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• v.35 no.4
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• pp.65-80
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• 2020

In this article, we review the study trends of three-dimensional (3D) displays that can display stereoscopic images from the perspective of a display device. 3D display technology can be divided into light field, holographic, and volume displays. Light field display is a display that can reproduce the intensity and direction of light or 'ray' in each pixel. It can display stereoscopic images with less information than a holographic display and does not require coherence of the light source. Therefore, it is expected that it will be commercialized before the holographic display. Meanwhile, the holographic display creates a stereoscopic image by completely reproducing the wavefront of an image using diffraction in terms of wave characteristics of light. This technology is considered to be able to obtain the most complete stereoscopic image, and the digital holographic display using a spatial light modulator (SLM) is expected to be the ultimate stereoscopic display. However, the digital holographic display still experiences the problem of a narrow viewing angle due to the finite pixel pitch of the SLM. Therefore, various attempts have been made at solving this problem. Volumetric display is a technology that directly creates a stereoscopic image by forming a spatial pixel, which is known as a volumetric pixel, in a physical space, and has a significant advantage in that it can easily solve the problem of the viewing angle. This technology has already been tested for commercial purposes by several leading companies. In this paper, we will examine recent research trends regarding these 3D displays and near-eye display that is emerging as a significant application field of these technologies.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.10
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• pp.135-141
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• 2013

In this paper, we installed three high brightness red, green, and blue LED in one socket and made one pixel unit. And we also developed the full-color display board module and control unit which can express various images such as text, graphics, video image with the combination of pixel units and a number of modules. LED display driver module have a driver circuit within the combination of the RGB pixel dot on unit area. These modules of the existing form can be high priced because of implementation a fixed resolution in specific space and installation space. To overcome these shortcomings, we developed a LED driver and LED pixel modules free in array at random pitch intervals. Display board module of this paper enabled to display smoothly video image which have many data processing quantity through dragging data speed up 36 frames per second. Also there are an effect which is provided more clear image because of improving the flickering of the existing display board.

• 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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• 2003.07a
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• pp.468-471
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• 2003

We firstly report liquid crystal shutter based on plastic film and its application to 3D shutter for stereoscopic displays. Plastic liquid crystal shutters have remarkable advantages compared to conventional glass liquid crystal shutters. They are thin, light and non-breakable so that very comfortable 3D shutter eye-wear can be realized using them. The concepts, optical performances and reliability test results of plastic film liquid crystal shutters are presented.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.32-33
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• 2009

We propose viewing angle switchable liquid crystal display(LCD) associated with fringe-field switching (FFS) mode with high aperture ratio characteristic. This device is composed of R(red), G(green), B(blue), pixel and W(white) pixel in which R,G,B pixel shows image and white pixel for both viewing angle control and image. Conventional viewing angle controllable liquid crystal display has not transmittance because the liquid crystal only tilts up without rotates in viewing angle control region. In this paper, we suggested that the device has high transmittance characteristic because the LC directors are rotated in which viewing angle control region are generated fringe electric field.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1809-1811
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• 1999

In recent years, attempts have been made to greatly improve the display quality of active-matrix liquid crystal display devices, and many techniques have been proposed to solve such problems as gate delay, feed-through voltage and image sticking. Gate delay is one of the biggest limiting factors for large-screen-size, high-resolution thin-film transistor liquid crystal display (TFT/LCD) design. Many driving method proposed for TFT/LCD progress. Thus we developed gate driving signal generator. Since Pixel-Design Array Simulation Tool (PDAST) can simulate the gate, data and pixel voltages of a certain pixel on TFT array at any time and at any location on an array, the effect of the driving signals of gate lines on the pixel operations can be effectively analyzed.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.5
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• pp.594-600
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• 2014

A threshold voltage compensation pixel circuit was developed for active-matrix organic light emitting diodes (AMOLEDs) using amorphous indium-gallium-zinc-oxide thin-film transistors (a-IGZO-TFTs). Oxide TFTs are n-channel TFTs; therefore, we developed a circuit for the n-channel TFT characteristics. The proposed pixel circuit was verified and proved by circuit analysis and circuit simulations. The proposed circuit was able to compensate for the threshold voltage variations of the drive TFT in AMOLEDs. The error rate of the OLED current for a threshold voltage change of 3 V was as low as 1.5%.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.879-882
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• 2009

A pixel isolation wall of liquid crystal display is fabricated by the anisotropic photoreaction of a cinnamate based prepolymer. The various oligomers containing a cinnamate moiety were synthesized and used for the formation of the pixel isolation wall. The anisotropic photoreaction of cinnamate moiety was closely related with the liquid crystal orientation at the polymer wall boundary.