Yoon-Hyoung Cho

Development of performance- and cost-oriented HD PDP TV with high picture quality using a high-efficiency hexagonal array structure

In this paper, we explained how we developed a 37-in. plasma TV satisfying the major requirements of HDTV. For performance improvement, a HEXA cell structure in delta subpixel array was chosen. To improve picture quality, a subpixel rendering algorithm was added. Finally, to investigate the suitability for a single-scan driver for cost reduction, the discharge characteristics were studied.

65.4: Improvement in Luminous Efficacy of Ultra‐Fine Discharge Cells for 50‐in. Full‐HD Plasma TV

In order to develop ultra-fine discharge cells with high luminous efficacy, several efforts have been made. We designed cell structures for the image element pitch of 0.58 mm. Both HEXA and MARI structures were considered. As for luminous efficacy, in constructing a 50-inch full HD PDP, we set a challenging goal to 2.0 lm/W. We believe high speed sustaining in high Xe content can help, because this is not restricted to small cell area. In addition, we developed ultra fine barrier fabrication method using sandblasting with 30 μm in width. This may contribute to improve efficacy further by enlarging discharge space.

P-82: Expectation of Luminous Efficacy of Ultra Fine Discharge Cells Using 2D-Simulator

It has been suggested that a 50-inch full HD class is the most ideal display device for digital broadcasting. One of the problems accompanied by the decrease of cell size is the reduction of luminous efficacy. This paper discusses difficulty of designing fine discharge cells and the influence of cell size reduction on the luminous efficacy is investigated using 2-dimensional simulation. The calculated results are verified by the experimental data obtained from 6-inch test panels with various pitches. It is found that in ultra fine discharge cells the luminous efficacy can be enhanced adopting high xenon operation along with high frequency driving.

19.4: An Image Improving Method for Delta Subpixel Displays

A method for improving the image quality on delta subpixel displays is proposed. We analyzed the causes of image deterioration problems in delta topology and developed a masking algorithm to improve the image quality on delta subpixel panels. Conditions under which the developed algorithm can be effectively used were identified. We succeeded in realizing significant improvements in real-time moving video under the recommended conditions.

A Study on High Frequency Sustaining Driver for Improving Luminance Efficiency of AC-PDP

Plasma display panel (PDP) has a serious thermal problem, because the luminance efficiency of the conventional PDP is about 1.5 lm/W and it is less than 3-5 lm/W of cathode ray tube (CRT). Thus there is a need for improving the luminance efficiency of the PDP. There are several approaches to improve the luminance efficiency of the PDP and we adopt the driving PDP at high frequency range from 400 kHz up to over 700 kHz. Since a PDP is regarded as an equivalent inherent capacitance, many types of sustaining drivers have been proposed and widely used to recover the energy stored in the PDP. However, these circuits have some drawbacks for driving PDP at high frequency range. In this paper, we investigate the effect of the parasitic components of PDP itself and driver when the reactive energy of panel is recovered. Various drivers are classified and evaluated whether it is suitable for high frequency driver, and finally current-fed type with DC input voltage biased is proposed. This driver overcomes the effect of parasitic component in panel and driver and fully achieves ZVS of all full-bridge switches and reduces the transition time of the panel polarity. It is tested to validate the high frequency sustaining driver and the experimental results are presented

12.1: Invited Paper: Performance- and Cost- Oriented Full-HD PDPs with High-Picture Quality for 42 in. or Smaller Sizes

The experience of developing 768/p PDPs in near 42 inches has encouraged industry to bring larger 1080/p applications to market. In the meantime, the efforts to realize 1080/p PDPs in near 42 inches may pave the way to empower the market competitiveness for 768/p applications in same size. It should take for a while to realize a moderately priced 1080/p PDP in 42 inches with high- performance and picture quality at the same time. However, candidate technology can also upgrade 768/p PDPs in near 42 inches progressively with exceptionally innovative engines. In another words, PDP business can still take benefit out of rapidly growing HDTV market by selling 768/p PDPs until timely introducing 1080/p products in 42 inches or smaller.

12.4: A Study on Full-High-Definition PDPs of under 50 in.

A method for realizing FHD PDPs of under 50 inches is proposed. We analyzed various arrangements of PDP. A Resolution-Efficient Delta (RED) arrangement is proposed. This elongates the gap between address lines. Using this, we could create 42-inch full HD class PDPs. The principal problem with this RED was image quality. We discovered what cause image deterioration and eliminated it.

32.3: Distinguished Student Paper: High Efficiency Hybrid PDP

In order to increase the effective yield of secondary electron emission from MgO protective layer, we used carbon nanotubes (CNTs) as a supplementary electron source for plasma discharge of PDP. CNTs were planted on the surface of transparent dielectric layer and coated with MgO in order to induce field emission of electrons under electric field formed during operation of PDP. Luminance and luminance efficiency of the panel with the CNTs were increased significantly, demonstrating a possibility of hybrid PDPs.

A high-luminous-efficacy PDP having multi-anodes for reduction of ionic effect (MARI)

— We propose a PDP having a new structure and driving scheme. An auxiliary electrode was inserted between X and Y electrodes. Driving and discharge stability was determined using a test panel. A 42-in. SD (852 × 480) panel and a 42-in. HD (1366 × 768) panel were also made having this new structure, and we verified the increase in luminous efficacy and the reduction of ionic losses. We achieved a luminous efficacy of 2.35 lm/W in an SD panel and 1.97 lm/W in a HD panel. Finally, we investigated the characteristics and merits of the new structure.

36.3: New Evaluation Method for the Inner Pin Distortion Problem of CRTs

A new evaluation method of the Inner Pin Distortion (IPD) has been developed. As the method does not require any displayed line on cathode ray tubes (CRTs), it can be commonly used by measurement and simulation. And the dependency of the IPD to CRTs inner curvature becomes clear by simulating