• Journal of Information Display
• /
• v.1 no.1
• /
• pp.20-24
• /
• 2000

We propose on a novel vertical configuration (VC) for a helix-deformed ferroelectric liquid crystal (HDFLC) display that has fast response, high contrast, analog gray scale capability, and wide-viewing characteristics. In contrast to a conventional HDFLC in a planar geometry, smectic layers arrange themselves parallel to the substrates, and thus, extremely uniform alignment of molecules in large area is naturally achieved in our new configuration without additional processes such as the rubbing and/or electric field treatment. Moreover, with a proper design of electrode patterns on the same substrate, multidomain switching is easily realized without employing any complex process of alignment. Our new VC-HDFLC is expected to provide a viable technology to produce a next-generation large area LCD suitable for processing the dynamic image at a video-rate.

• Journal of Information Display
• /
• v.1 no.1
• /
• pp.3-8
• /
• 2000

We have developed a high performance vertical alignment TFT-LCD (Thin Film Transistor Liquid Crystal Display), that shows a high light transmittance, and wide viewing angle characteristics with an unusually high contrast ratio. In order to optimize the electro-optical properties we have studied the effect of cell parameters, multi-domain structure and retardation film compensation. With the optimized cell parameters and process conditions, we have achieved a 24" wide UXGA TFTLCD monitor (16:10 aspect ratio 1920X1200) showing a contrast ratio of over 500:1, panel transmittance near 4.5%, response time near 25 ms, and viewing angle higher than 80 degree in all directions.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2003.07a
• /
• pp.563-566
• /
• 2003

We present wide-viewing characteristics of a twisted nematic liquid crystal display (TN LCD) achieved by adopting dielectric surface gratings (DSGs) as alignment layers. The experimental data and the numerical analyses consistently show that the optical compensation effect inherent to the TN LCD with the DSGs greatly reduces the contrast inversion of the TN LCD.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2004.05a
• /
• pp.153-156
• /
• 2004

We have studied electro-optic characteristics of transflective liquid crystal display (LCD) using in-plane switching mode. Unlike previous transflective LCD using a dual gap structure and multi driving circuit, this transflective LCD has a single gap structure and a single driving circuit. In the voltage on state, the electric field is applied horizontally to the LC directors, and then homogeneously aligned LC directors at initial state is rotated to with the electric field. But the twist angle of the LC directors in reflective area is lower than transmissive area. As a result, it is possible to design the transflective LCD with a single gap and a single driving circuit. The transflective display associated with this LC cell exhibits a wide viewing angle in both reflective and transmissive areas.

• Journal of Urban Science
• /
• v.9 no.1
• /
• pp.61-68
• /
• 2020

Steps are very common features in our living environment. Unfortunately, the occurrence of accidents on steps is thus inevitable. A failed visibility to recognize a step remains the most common attribute in these accidents. In this research, sensory scales of step visibility were created in order to examine the effects of two factors on step visibility in sensory testing methods; observation height from floor and eye condition while viewing a step from the descending direction. Results of sensory tests revealed strong influence of eye condition on step visibility. Influence of visual characteristics of each step was also examined and clarified.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.06a
• /
• pp.85-86
• /
• 2008

We have developed charged particle type display using opposite-charged two particles. We fabricated the charged particle type display to be controlled the addressing layers by putting voltage. To get the effect of number of layers, we measured driving voltage, reflectivity, viewing angle, and color characteristics, for 1~2 layer. Reflectivity was different according to the number of layers and wavelength of yellow particles is alike to that.

• Journal of Information Display
• /
• v.2 no.1
• /
• pp.1-4
• /
• 2001

We propose a dual in-plane parallel electrode structure of a vertical configuration of a helix-deformed ferroelectric liquid crystal (HDFLC) mode for better brightness than a single in-plain electrode case. This structure provides high brightness in addition to the analog gray scale capability, fast response, and wide-viewing characteristics. In contrast to a conventional HDFLC in a planar geometry, smectic layers arrange themselves parallel to the substrates and thus extremely uniform alignment of molecules in a large area is naturally achieved in our new configuration.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.16 no.2
• /
• pp.131-137
• /
• 2003

We have performed computer simulation to obtain electro-optic chracteristics of reflective liquid crystal display (LCD) using wide viewing angle LC mode, fringe field switching(FFS). Unlike other reflective LCD modes, in the FFS mode, the LC director in plance so an application to reflective display consisted of polarizer, LC layer and reflector is possible. when an incident light is 550mm, the optimal cell retardation value is 0.1365${\mu}$m and the efficiency of reflectivity is high over 90% with very little wavelength dispersion. Further, we have studied a new reflective display with polarizer, optical compensation film with half plate, LC plus reflector. The display with optimized cell parameters shows high contrast ratio (CR) over 130 with high light efficiency over 90% at normal direction and the CR greater than 5 exists over 60$^{\circ}$ of polar angle in all directions.

• Current Optics and Photonics
• /
• v.8 no.3
• /
• pp.307-312
• /
• 2024

Measuring the three-dimensional (3D) spatial light intensity distribution of an autostereoscopic multiview 3D display at the user position is time-consuming, as luminance has to be measured at different positions around the user position. This study investigates a method to quickly estimate the 3D distribution at the user position. For this purpose, a measurement setup using a white semitransparent diffusing screen or a two-dimensional (2D) spatial sensor was devised to measure the 2D light intensity distribution at the user position. Furthermore, the 3D spatial light intensity distribution at the user position was estimated from these 2D distributions at different viewing distances. From the estimated 3D distribution, the characteristics of autostereoscopic 3D display performance can be derived and the candidate positions for further accurate measurement can be quickly determined.

• Journal of the Korean housing association
• /
• v.16 no.6
• /
• pp.121-128
• /
• 2005

This study investigates the design features of pilotis applied to 20 high-rise apartment housings in Korea, completed between January 2000 and August 2005. It analyzes the design characteristics of pilotis on the basis of its spatial configuration and the residents' behavior and suggests the directions of pilotis design in the future. The study finds the followings. 1) The pilotis spaces in foreign apartment housings are used mainly for communal functions such as the passages between buildings for both pedestrians and vehicles. Compared with this public use of pilotis in foreign counterparts, the pilotis spaces in Korean apartment housings are semi-private and have multiple purposes. 2) The pilotis design can be classified on the basis of the spatial configuration elements and the patterns of residents' behavior. The spatial configuration elements consist of ceiling, column, wall, and floor; the residents' behavior can be classified as viewing, resting and playing, driving and parking, and keeping privately-owned objects such as motorcycle and bicycle. 3) Two spatial configuration elements, the wall and the ceiling and two behavioral patterns, 'resting and playing' and 'viewing' are getting more attention by designers in the apartment housings analyzed in this study.