Byung-chul Ahn

Development of a 42‐in. 2‐D/3‐D switchable display using multi‐view technology for public‐information‐display applications

— A 42-in. 2-D/3-D switchable display operating in a parallax-barrier-type system consisting of liquid-crystal displays (LCDs) has been developed. The system displays 2-D images in full resolution, without any degradation to the original 2-D images, and 3-D autostereoscopic images with resolutions higher than SVGA with wide viewing zones electrically controlled by the parallax-barrier system. The system is intended for use in public-information displays (PIDs), a booming field, and as displays for gaming, medical, and simulation applications.

The development of 42” 2D/3D switchable display

Abstract Stereoscopic/autostereoscopic systems have been developed to express 3D images, but have not been successfully use in practise. In order to apply 3D display to promising applications such as advertisements and games, we developed a 42” 2D/3D switchable display. It has characteristics that do not require special glasses for 3D images, uses multi‐view technology for improving 3D viewing characteristics, and has a 2D/3D switching function to express dynamic 3D contents as well as conventional 2D contents.

Analysis of Electro-Optic Properties of a Polymer Network Liquid Crystal Display with Crossed Polarizers

An active-matrix polymer network liquid crystal display (AMPNLCD) of 1.79″ QCIF(176 × 144) was fabricated. The operating mode of normally black was reversed to normally white by using crossed polarizers. The contrast ratio, as a result, was drastically increased, which was comparable to a conventional liquid crystal display. The response time at a typical driving voltage, 2.8 V, was also fast enough to play still image smooth. The electro-optic properties of AMPNLCD with crossed polarizers were evaluated and discussed.

26.3: High-Performance EEFL Backlight System for Large-Sized LCD-TV

We suggest the novel EEFL (External Electrode Fluorescent Lamp) Backlight System 3 types; the first aspect is a high optical efficiency second is reduction of mechanical size of Backlight, and the last is low power consumption in large LCD Backlight System. To gain a high optical efficiency, we consider the narrow diameter (φ 3.0) lamp of EEFL Backlight System. As the impedance of the narrow diameter (φ 3.0) lamp is higher than that of conventional (φ 4.0) EEFL. A high impedance of lamp is caused the increase of power consumption and a driving voltage of lamp. But its characteristic of an enhancement luminance could be possible for a high optical efficiency. We introduce a method for decrease of a mechanical size for large Backlight. The length of electrode for EEFL system must be increased as a small diameter and a long length of lamp. For that reason is caused the increase of Bezel Size For LCD TV. In this paper, we suggest a DEFL(Differential Diameter External Electrode Fluorescent Lamp). DEFL is made by junction between φ 4.0mm glass tube of emission part and φ 8.0mm glass tube of electrode part. Finally we explain φ 4.0mm EEFL system for low power consumption in comparison with φ 4.0mm CCFL backlight system.

Fabrication of TFTs for LCD using 3‐mask process

Abstract A new technology for reducing photolithography process from a four step to a three step process in the fabrication of TFT LCD is introduced. The core technology for 3‐mask‐TFT processes is the lift‐off process [1], by which the PAS and PXL layers can be formed simultaneously. A different method of the lift‐off process was developed in order to enhance the performance of efficiency with conventional positive and not negative PR which is the generally used in other lift‐off process. In addition, the removal capacity of the ITO/PR in lift‐off process was evaluated. The evaluation results showed that the new process can be run in conventional TFT production condition. In order to apply this new process in existing TFT process, several tests were conducted to ensure stability of the TFT process. It was found that the outgases from PR on the substrate in ITO sputtering chamber do not raise any problem, and the deposited ITO film beside the PR has conventional ITO qualities. Furthemore, the particles that were produced due to the ITO chips in PR strip bath could be reduced by the existing filtering system of stripper. With the development of total process and design of the structure for TFT using this technology, 3‐maskpanels were achieved in TN and IPS modes, which showed the same display performances as those with the conventional 4‐mask process. The applicability and usefulness of the 3‐mask process has already verified in the mass production line and in fact it currently being used for the production of some products.

P-80: External Electrode Fluorescent Lamps and Backlight Units for the Large Area of 32″∼42″ LCD-TVs

The commercialized EEFL-BLUs of 32″, 37″, and 42″ LCD-TVs are reported with respect to the basic characteristics of luminance and efficiency. The capacitive and resistive reactance is also presented to design the inverter for lamps and BLUs.