AC Plasma Display Panel Research Articles

Influence of sustaining frequency on the production efficiency of excited Xe atoms studied in unit cell microplasma for ACPDPs using spectroscopic diagnostics

Abstract— The effects of the driving frequency of the sustaining‐voltage pulses on microplasmas in a cell of an ac plasma‐display panel (ACPDP) were investigated using spectroscopic diagnostics [optical emission spectroscopy (OES) and laser‐absorption spectroscopy (LAS)]. The unit discharge cell has a structure similar to that of a general commercial ACPDP, but it is prepared for three‐dimensional (3‐D) observation using a pair of micro‐prisms. When the near‐IR emission by OES and the absorption signal by LAS were observed in the front and side views simultaneously, it was determined that the discharge was concentrated at the center of the discharge space and quickly responded to an applied electrical potential as the sustaining frequency increases. The production efficiency of excited Xe**(2p) atoms and vacuum‐ultraviolet (VUV) photons, which was estimated from the spectroscopy results with the measured power dissipated in the discharges, increased as the frequency of the sustain pulses increases to 100 kHz. At 250 kHz, however, the efficiency remarkably decreased because of an inefficient time for excimer formation and, possibly, for wall‐charge formation. From the quantitative analysis of the efficiency, the most‐efficient frequency for the sustain voltage was around 100 kHz in the case of Xe(5%)‐Ne at 500 Torr, i.e., the efficiency depended on both the priming particles [excited Xe*(1s5) atoms] in space and the charged particles on the dielectrics.

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

AbstractIn 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.

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

AbstractThe 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.

The Effects of Sustain Electrode Gap Variation on the Luminous Efficacy in Coplanar-Type AC Plasma Display Panel Under Low- and High-Xe Content Conditions

We investigated the effect of sustain electrode gap variation with various Xe content gas in a coplanar-type ac plasma display panel through 2-D numerical simulation to understand the inherent high-luminous-efficacy mechanism. For the low-Xe content gas condition of 5%, the optimal sustain electrode gap was found to be about 200 mum, because of the steep decrease of electric power delivered to electrons with the increase of electrode gap longer than 200 mum. On the other hand, with the high-Xe content gas of 20%, the efficacy continuously increased as the electrode gap increased beyond 200 mum . We have found that the high luminous efficacy under the condition of long electrode gap and high-Xe content gas is due to the high-electron-heating efficacy in the cathode sheath region

A New AC Plasma Display Panel With Auxiliary Electrode for High Luminous Efficacy

A new ac plasma display panel (PDP) for high luminous efficacy is proposed, and its characteristics are investigated. The new ac PDP has a coplanar gap of 200 mum and an auxiliary electrode located between the scan and common electrodes. The periodic pulses are applied to the auxiliary electrode during the sustain period, which plays the roles of enhancing the infrared emission and reducing the discharge current. The sustain voltage decreases with the increase of the auxiliary pulse voltage until 80 V. When the voltage of the pulse applied to the auxiliary electrode is 50 V, the luminous efficacy reaches its peak value and is approximately 8.7 lm/W obtained from the measurement of Ne + 20% Xe gas-mixture discharges in the green cells. The luminous efficacy of the new proposed test ac PDP with Ne + 13% Xe and Ne + 20% Xe gas mixtures is improved by 190% and 320%, respectively, compared to that of the conventional ac PDP with a Ne + 13% Xe gas mixture

Energy Recovery Circuit with Auxiliary Power Supply for AC Plasma Display Panel

A new energy recovery circuit with an auxiliary power supply for AC plasma display panel is proposed, which can provide zero-voltage switching of all switches by rejecting the surge current when sustain switches are turned on. The operation process of the circuit is analyzed, and the results of experiments based on a 12-in PDP panel with 100 kHz sustaining frequency show that the proposed circuit could reduce power losses of energy recovery circuit of AC plasma display panel.

Material Properties and Plasma Display Panel Discharging Characteristics Depending on MgO Evaporation Rate

MgO thin film is most widely used as a protecting layer in ac Plasma Display Panel. The film is deposited using electron beam evaporation. The effects of the evaporation rate of MgO film deposited using an electron beam on the MgO properties and the discharge characteristics of the plasma display panel (PDP) were investigated. The evaporation rate was changed from 3 to 15 Å/s at a substrate temperature of 300 °C. MgO properties such as crystal orientation, surface roughness, contact angle, and film structure were inspected using X-ray diffraction (XRD), analysis atomic force microscopy (AFM), drop shape analysis, and secondary electron microscopy (SEM). The MgO properties were shown to be strongly dependent on the evaporation rate. We also studied the relation between MgO properties and PDP discharging characteristics. The minimum firing voltage and maximum luminous efficiency were obtained at an evaporation rate of 5 Å/s. In the MgO film deposited at 5 Å/s, the (200) orientation was most intensive and surface roughness was minimum.

IGBT-Based Cost-Effective Energy-Recovery Circuit for Plasma Display Panel

A new insulated-gate-bipolar-transistor (IGBT)-based cost-effective energy-recovery circuit (ERC) for a plasma display panel (PDP) is proposed. Since it is composed of two small resonant inductors and four power diodes instead of the conventional large auxiliary circuit, it features a simpler structure, less mass, fewer power devices, higher efficiency, and lower cost. Since all its power switches are turned off under the zero-current switching operation, IGBTs can be employed as power switches. Moreover, the very stable and uniform light emitted from a PDP proves the high quality of screen. Therefore, it is well suitable for the consumer-affordable hang-on-the-wall TVs which have the desirable features such as thinness, lightness, high efficiency, low price, etc. To confirm the validity of the proposed ERC, a comparative analysis and experimental results based on a whole ac PDP driver equipped with the proposed circuit for the 42-in PDP are presented

Effects of Kr,$hboxN_2$, and Ar on Address Discharge Time Lag in AC Plasma-Display Panel With High Xenon Content

The additive gas effect on the discharge time lag of the address pulse was investigated in an ac plasma-display panel (PDP) with a Ne+13% Xe gas mixture. A small amount of Kr, N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , and Ar gas, respectively, was added to a Ne+13% Xe gas mixture to improve the address discharge time lag of an ac PDP. It was found that the address discharge time lag was improved by adding a small amount of Kr gas (up to 2%) to the Ne+13% Xe gas mixture and thereafter worsened. In the case of the addition of Ar gas to Ne+13% Xe, the discharge time lag of the address pulse was not improved. The concentration of N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> in the Ne+13% Xe gas mixture was varied from 0.013% to 0.187%, and its effects on the address discharge time lag were investigated. The time lag for the address discharge with a Ne+13% Xe+0.013% N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> gas mixture was improved

Study on discharge stability of cost-effective driving method based on V/sub t/ close-curve analysis in AC plasma-display panel

A new cost-effective driving method that can drive plasma-display panel cells without applying any driving waveform to the common electrode is proposed based on a V/sub t/ close-curve analysis. In this driving method, it is very important to prevent a misfiring discharge due to the inversion of the polarity of the wall charges accumulated between the scan and address electrodes. The measured V/sub t/ close-curve showed that a misfiring discharge caused by the polarity inversion phenomenon of the wall charges on the scan and address electrode could be prevented by minimizing the potential difference between the scan and address electrodes by applying a positive auxiliary pulse to the address electrode, especially while applying the positive sustain pulse during a sustain period. As a result, the proposed cost-effective driving method can reduce the driving cost by about 20% through eliminating the common driving board and successfully display various image patterns, such as the white, red, green, and blue patterns, on a 42-in plasma television without any misfiring discharge.

A new driving waveform for improving luminous efficiency in AC PDP with large sustain gap under high Xe content

A new driving waveform is proposed to improve the luminous efficiency of alternating current (ac) plasma display panel with a large sustain gap (400 /spl mu/m) structure under a high Xe (15%) gas mixture. Due to the large sustain gap structure, the reset waveform was modified based on Vt close curve analysis to produce the surface discharge between the scan and sustain electrodes by applying the negative bias voltage on the sustain electrode during a ramp-up period. During a sustain period, the sustain waveforms with two different voltage polarities, i.e., positive and negative voltage levels, were applied, thus resulting in producing an efficient discharge by accumulating the wall charges uniformly among the three electrodes. As a result of adopting the proposed driving waveform, the luminance of 330 cd/m/sup 2/ and luminous efficiency of 4.5 lm/W under the sustain voltage of 210 V and the trigger voltage of 160 V were obtained in the 6-in plasma display panel (PDP) with green phosphors under a large sustain gap (400 /spl mu/m) and a high Xe (15%) gas mixture.

High-speed driving method using bipolar scan waveform in AC plasma display panel

This paper proposes a new high-speed driving method using the bipolar scan waveform with a scan width of 1 /spl mu/s in an ac-plasma display panel. The bipolar scan waveform in an address period consists of a two-step pulse with two different polarities, i.e., a forward scan pulse with a negative polarity and reverse scan pulse with a positive polarity, which can produce two address discharges, including a primary address discharge for generating wall charges and secondary address discharge for accumulating wall charges. To produce the fast address discharge stably using the bipolar scan pulse during an address period, a new reset waveform is designed based on a V/sub t/ close curve analysis, and the address discharge characteristics examined under various reset and address waveforms. As a result of adopting the proposed driving method, a high-speed address with a scan width of 1 /spl mu/s is successfully obtained when using a checkered pattern on a 4-in test panel.

Cell parameter extraction method for AC plasma display panels

This paper presents a cell parameter extraction method for three-electrode AC plasma display panels (PDPs). This method uses three different two-electrode AC discharges to extract the cell capacitances. The drive point capacitances of the cell with and without a two-electrode dark discharge were measured, and the cell capacitances were extracted from them. The extracted cell capacitances agree well with those obtained from a three-dimensional electromagnetic simulation. Electrical equivalent circuits of the plasma were constructed using Jung's model [Y.K. Jung, J.W. Seo, Y.H. Kim, B.K. Kang, Circuit model for two-electrode AC discharge, IEEE Trans. Plasma Sci., 31(3), pp. 362–368, 2003.] and the measured firing voltages. A circuit model for the cell was constructed using the cell capacitances and the equivalent circuits for the plasma. The results of electrical simulation using this circuit model agree well with the measurements, indicating that the presented circuit model would be useful for simulating the electrical behaviors of a three-electrode AC PDP.

P-107: High Resolution and High Luminous Efficacy AC Plasma Display Panel

High resolution AC plasma display panel with a pixel of 0.27 mm × 0.81 mm adopted the auxiliary electrode and coplanar-gap of 200 μm. The luminous efficacy of the proposed structure was investigated. The maximum luminous efficacy of the Ne+13%Xe gas-mixtures in the proposed structure with high resolution pixels was about 4 lm/W (green cells). The luminous efficacy of the proposed panel increased as the voltage of the pulses applied to the auxiliary electrode increased until 50 V.

P-99: Effects of Width of Address Electrode on Sustain and Address Discharge Characteristics in AC Plasma Display Panel

The width of an address electrode is an important parameter to affect both the address and sustain discharge characteristics in AC-PDP. It is found numerically that as the width of an address electrode is wider, the capacitance between the sustain and address electrodes (CAY) increases but the capacitance between the two sustain electrodes (CXY) decreases. The resultant changes in the sustain and address discharge characteristics, such as a firing voltage, sustain voltage, discharge delay time and full-white luminance were examined in the 50-in. ac-PDP with a high Xe (>10 %) content. The increase in the address electrode width causes an increase in the firing and sustain voltage between the sustain electrodes, which are due to the decrease in the capacitance between two sustain electrodes and the increase in the wall charges accumulation toward the address electrode. In particular, the full-white luminance increases with an increase in the address electrode width. As the address electrode width becomes broaden, the sustain discharge path is lengthened toward the address electrode and the discharge volume is also enlarged. Therefore, the amount of the IR, VUV and Ne rays can be emitted considerably.

P-100: High Definition AC PDPs with Front Address Structures

8-inch High Definition (corresponding to 50″ Full HD (1080p)) AC Plasma Display Panels with front address structures are developed. These structures show high luminous efficacy without increasing address voltages even if the cells are high definition.

P-106: Improvement of Luminance and Luminous Efficiency Using New Negative Sustain Waveform in AC-Plasma Display Panel

A new negative sustain waveform is proposed to improve the sustain and address discharge characteristics of PDP. The effects of conventional positive and proposed negative sustain waveforms on the sustain and address discharge characteristics are examined and compared in the 7-in. test panel with a Ne-Xe (4 %), gas mixture at 100 kHz. In the case of adopting the proposed negative sustain waveform, the luminance and luminous efficiency were improved by about 10 % and 16 %, respectively.

Reset-While-Address (RWA) Driving Scheme for High-Speed Address in AC Plasma Display Panel With High Xe Content

A new reset while-address (RWA) driving scheme for a single scan of an XGA grade (1024 /spl times/ 768) ac-plasma display panel (PDP) is proposed to improve the address discharge characteristics with a high Xe gas mixture (15%). To solve the conventional address problem of the gradual decrease in priming particles during an address period, the falling ramp waveform in the reset period is separated into two parts; the first part is applied at the beginning of the reset period and provides the priming particles during the first half of the address period, while the second part is applied in the middle of the address period to provide an additional supply of priming particles during the second half of the address period. As a result of adopting the proposed RWA driving scheme, address discharges were successfully produced within a 1.0-/spl mu/s pulsewidth due to the presence of priming particles throughout the address period.

Striations in Plasma Display Panel

The phenomenon of striation has been investigated experimentally in amacroscopic ac-plasma display panel (PDP). The relationship between thecharacteristics of striation and the operation conditions includingvoltage, frequency, rib, and electrode configuration, etc is obtainedexperimentally. The origin of the striations is considered to be theionization waves in the transient positive column near the dielectricsurface in the anode area during the discharge, and the perturbation iscaused by resonance kinetic effects in inert gas.

Luminance control method for a given gray level by asymmetric sustain pulses in AC PDP

A possible method to control luminance of a whole panel in an ac plasma display panel (PDP) is to control a total number of sustain pulses which is called as gray level control. However, this method leads to rough step-like luminance control especially in the low gray level. In this paper, a simple and robust luminance control method of whole panel is proposed. The key feature of the proposed driving technique is application of asymmetric amplitude modulation of sustain pulses in the display period of the address, display-period separation (ADS) driving scheme. As a result, the range of luminance control by the proposed method is about 50% of the luminance for a given gray level. Moreover, it is experimentally verified that the proposed method has similar dynamic margin performances compared with the conventional method.