Byung-Hak Lee

Prevention of Boundary Image Sticking in an AC Plasma Display Panel Using a Vacuum Sealing Process

Boundary image sticking can be inherently prevented in an ac plasma display panel fabricated using a vacuum sealing process. The results indicate that residual impurities, such as nitrogen or oxygen, are essentially related to the production of boundary image sticking. When checking the production of boundary image sticking in a test panel fabricated using a or an flow during the vacuum sealing process, no boundary image sticking appeared in the case of a flow, whereas boundary image sticking was produced with an flow, although the test panel was fabricated using a vacuum sealing process. Consequently, reducing the residual impurity, particularly oxygen, based on a vacuum sealing process can inherently prevent boundary image sticking.

39.2: The Full‐Color Video Images with Uniquely‐Gated Carbon Nano‐tube Field Emission Displays

Thick-film printing processes have been applied for preparing a carbon nanotube field emission display (c-FED), which has a strong cost advantage for large-size flat panel display. For practical display applications, two types of the gated cathode structure named the normal-gate cathode and the under-gate cathode have been developed and improved. The normal-gate and the under-gate cathode structures have the driving voltages of ±35 V and ±65 V, respectively. The 5″ c-FED panel with the normal-gate cathode and the 7″ c-FED panel with the under-gate cathode were successfully implemented and excellent full-color video images were obtained.

43.3: Discharge Characteristics of 42‐in. AC Plasma Display Panel Fabricated by Vacuum Sealing Method

The base vacuum level before filling a discharge gas is an important parameter to affect both the address and sustain discharge characteristics in an AC-PDP. for the improvement in discharge characteristics, the vacuum sealing method is adapted. In this paper, the vacuum sealing method to enhance a base vacuum level is adopted to minimize the residual impurity gas, and the resultant changes in the address and sustain discharge characteristics, such as a dynamic voltage margin, firing voltage, statistical address delay time, and secondary electron coefficient, were examined in comparison with the conventional sealing method in the 42-in. AC-PDP with a high Xe (11 %) content. The high base vacuum level in the 42-in. panel fabricated by the vacuum sealing method can enhance the discharge characteristics, such as a dynamic voltage margin, a firing voltage, and a statistical address delay time, which are caused by a decrease in the residual impurity gases and an increase in the secondary electron coefficient. In particular, in the vacuum sealing method, the sustain voltage was decreased by about 30 V, and the address voltage was also decreased by about 7V in the Xe (11 %) condition.

24.3: Experimental Study on Halo‐Type Boundary Image Sticking in 42‐in. AC Plasma Display Panel

When displaying the square-type image with peak luminance for about 500 hours in 42-in. PDP-TV with high Xe (15 %) content, the luminance and IR (828 nm) emission of the non-discharge region adjacent to the discharge region were observed in comparison with the discharge region and non-discharge region far away from the discharge region, under the two different image patterns, such as the dark and full white backgrounds. In particular, the halo-type boundary image sticking was observed in the non-discharge region adjacent to the discharge region. Under the dark background, the IR was initiated the fastest and the luminance was the highest in the regions adjacent to the discharge region, whereas under the full white background, the IR was initiated the fastest in the region adjacent to the discharge region but its luminance was higher than that of the discharge region and lower than that of the region far away from the discharge region. The halo-type boundary image sticking phenomenon is due to the re-deposition of the MgO on both the MgO and phosphor layers in the non-discharge region adjacent to the discharge region, which is confirmed by the Vt close curve, Mg-profile and SEM analyses.

55.1: Invited Paper: Solution to Boundary Image Sticking in AC Plasma Display Panel

In this paper, the two kinds of solutions to remove a boundary image sticking of an ac plasma display panel are introduced. One solution is to completely recover the boundary image sticking cells by means of full white aging process. It was observed that after the 100-hour full-white aging process of the PDP cells with boundary image sticking, the MgO surface morphology in the boundary region with image sticking region was similar to that in the region with no image sticking. The other solution is to prohibit inherently the production of the boundary image sticking by sealing the PDP panel under a vacuum condition. In the panel fabricated by the vacuum sealing method, no boundary image sticking phenomenon was observed.

P-252L: Late-News Poster: Three Dimensional Spatiotemporal Behavior of Infrared and Visible Emission from Discharge Plasma of AC PDP

A test panel for three-dimensional spatiotemporal observation in AC plasma display panel (PDP) has been successively fabricated and studied with ICCD camera. The frequency dependence of three-dimensional spatiotemporal behavior has been experimentally investigated in sustain discharge. In addition, the weak discharge characteristics in reset period and two different discharge modes in address period will be discussed below.

55.4: Influence of He Contents on Reset and Address Discharge Characteristics Under Variable Panel Temperature in ac PDPs

The effects of He content in He-Ne-Xe (11 %) on the reset and address discharges were examined under variable panel temperature ranging from −5 to +65°C. The changes in the firing voltages under the X-Y surface or the A-Y plate-gap discharges were measured using the Vt close-curve method when the He contents and panel temperature were varied. Under the variable panel temperature condition, the IR emission intensities were also monitored during the reset and address discharges when the He contents were varied from 0 to 50 %. It was observed that as the panel temperature was increased, the higher He content could facilitate the reset and address discharges.

Triode‐type field emission displays with carbon nanotube emitters

Abstract Carbon nanotube emitters, prepared by screen printing, have demonstrated a great potential towards low‐cost, large‐area field emission displays. Carbon nanotube paste, essential to the screen printing technology, was formulated to exhibit low threshold electric fields as well as an emission uniformity over a large area. Two different types of triode structures, normal gate and undergate, have been investigated, leading us to the optimal structure designing. These carbon nanotube FEDs demonstrated color separation and high brightness over 300 cd/m2 at a video‐speed operation of moving images. Our recent developments are discussed in details.

15.3: Anti-Electromigration of Lead-Free Ag/Frit Modified Address Electrodes in PDPs

We have studied on the usage reduction and anti-migration properties of newly formulated lead-Free (Bi-based) Ag/Frit modified address electrode (hereinafter VE electrode) systems in PDPs (Plasma Display Panels). It is thought that their high performance such as anti-migration and the cost-competitiveness without any loss of performance in paste, process and luminous efficacy are originated from the optimum controlling of Ag/Frit weight ratio and low specific gravity by low Ag contents, respectively. Currently, lead-free VE electrodes are being applied as main electrode materials of PDP panels fabricated by SDI photo-imageable patterning process including ultra-fine resolution models.

Modified ramp‐reset waveform robust for variable panel temperature and its discharge characteristics

Abstract By the voltage threshold (Vt) close‐curve measurement method, the changes in the discharge characteristics such as a firing voltage and IR emission among the three electrodes were examined relative to the low or high panel temperature ranging from ‐10 to 80°. The variation in the panel temperature was found significantly influence the surface discharge between the MgO surfaces rather than the plate gap discharge between the MgO and phosphor layers. Based on this experimental observation, a modified reset waveform that alleviates the surface discharge during a ramp‐up and ‐down period was deeloped. By adopting the proposed reset waveform, a stable address discharge could be obtained irrespective of the panel temperature variation.