PDP Panel Research Articles

13.1: New Improvement of Luminous Efficacy by Applying CaxMg1‐xO Protecting Layer with High Xe‐content Discharge Gas

AbstractThe easy formation of CaCO3 and MgCO3 in manufacture process posed big challenge to mass production of high luminous efficacy PDP panel that applying CaxMg1‐xO(CMO) protecting layer. New approaching of applying CMO and improving process allows significant improvement of reducing the impact of carbonate formation on the performance of CMO panel, over 25% increase of the luminous efficacy has been achieved in the 2nd generation CMO panel.

Dynamic Location Allocation Optimization for PDP Panel Aging Stereoscopic Warehouse

To optimize the storge and retrieval process for Plasma Display Panel (hereafter abbreviated as PDP) panel aging, one dynamic cargo location allocation method is proposed, and one access time model is also established to achieve the shortest location allocation for the PDP panel aging steroscopic warehouse based on expert system. The constraints of the optimization model include redundancy requirements of steroscopic warehouse, PDP panel aging stacker running speed, time requirements, in-out warehouse strategy requirements and so on. Tests show that the dynamic location allocation system of the PDP panel aging steroscopic warehouse based on expert system is of high stability and can save energy consumption and time consumption in the access process, thus meets the actual requirements of production.

Enhanced luminescence and degradation resistance in Tb modified Yttrium Borate core–nano silica shell phosphor under UV and VUV excitation

Composition variation in optimized solid state reaction conditions has been done to achieve intense green emission in YTb x BO 3 phosphor under UV and VUV (147 nm resonant Xe*, 172 nm Xe 2* excimer band) excitation. Inert interface layer created by fabricating a shell of silica nanoparticles over individual phosphor grain protected the phosphor surface from deterioration and oxidation of luminescent ion (Tb 3+) thus completely arresting phosphor degradation. At optimum Tb content of 20 mol%, integrated photoluminescence intensity of developed YTb x BO 3 phosphor is four times higher than commercial green YBT. With short decay time of 4 ms, YTb x BO 3 core–nano silica shell green emitting phosphor has great application potential in PDP panel and phosphor coated Xe lamps.

The enhancement of the BRCR (Bright Room Contrast Ratio) in a plasma display panel

Luminous efficiency and Bright Room Contrast Ratio (BRCR) are critical issues in a plasma display panel. In the conventional PDP panel structure, an optical filter is used to reduce the reflected luminance and to increase the BRCR. However, this optical filter reduces the peak luminance also, resulting in a decrease in the luminous efficiency. In this study, a new electrode structure with the enlarged black stripe and the auxiliary electrode between the bus and ITO electrode was proposed to investigate the possibility of getting higher BRCR without an optical filter. The experimental results using 3 in. test panels in this study showed that the BRCR of the new structure was enhanced to more than twice of that of the conventional one without any loss of the luminous efficiency.

19.1: Design of 3‐D PDP with Fast‐Decaying Phosphor

AbstractDesigned PDP exhibits good quality picture in 3D and normal modes. We selected several phosphors of red and green cell under 4ms decay time. for red color (Y,Gd)2O3: Eu3+ phosphor was adopted due its short decay time and high luminescence. Mixture of Zn2SiO4: Mn2+, (Y,Gd)Al3B4O12: Tb3+, and Y3Al5O12: Ce3+ was used as green phosphor. Decay time, luminance, and color coordinate of 3D PDP panel and Moving picture image quality of 3D PDP TV‐set are discussed.

Automatically Rotating PDP TV Using Multiple Sensor Information

Most display units such as advertizing panels and mannequins in Exhibition halls or Big Shopping Malls are static. This study proposes the concept of active display system. An automatically rotating TV is chosen as an example device. The active display system detects the presence and location of customers and provides a clear screen view for customers. Initially, three passive infrared (PIR) sensors are used to detect the position of customers. Next, to cope with shortcoming of PIR sensor, a sensor fusion method combining three PIR sensors and an ultrasonic sensor is proposed. The performance of the proposed algorithms has been verified through experiment of a PDP panel TV. Finally, a sensor network is employed to control multiple PDP TVs simultaneously by sharing information between display units.

P‐145: Influence of Crystal Structure of Doped MgO on Jitter Time in SM‐PDP

AbstractThe effect of the MgO crystal structure on the addressing discharge jitter in SMPDP is investigated. By varying the oxygen pressure during E‐beam deposition, different MgO crystal structure was made, as analyzed by XRD. The jitter time in a PDP panel was measured for isolated On‐pixels at low intensity levels. The conclusion is that the jitter time can be decreased by maximizing the relative (200)/(111) peak ratio, obtained by decreasing the O2 addition during E‐Beam MgO deposition.

15.1: Improvements Made to the Contrast Ratio of PDPs in a Bright Room by Coating the Phosphors with Pigments

AbstractIn order to improve the contrast ratio of PDPs in the bright room, the reflection luminance of the panel needs to be decreased while the luminance is increased. In this particular process, we decreased the panel reflection by coating the phosphors with pigments of each color. In order to minimize the loss of brightness, we did not coat the green phosphor with its respective pigment. The main reason this was not done was due to the fact that the green phosphor is the most important emission material for the brightness of PDPs, but the green pigment is the most ineffective material in lowering the reflectance. This technique was applied to a 50″ PDP panel. The results showed a contrast ratio increase of 15% without any sacrifice of the luminance by just adjusting the transmittance of the front filter.

Characterization of Residual Stress and Pore Distribution in Sealed Area of Large PDP Panel

Residual stress of front and rear glass substrates and remained pore in sealed areas of AC-PDP panel were measured to see the trend of the characteristics of sealed area as the panel size of PDP increased. For this, we compared these characteristics of 6″, 42″ and 80″ panels, between the corner side & straight line, the vertical & horizontal sides, and the around area of ventilation port & area far from that each. Residual stress was measured by the automatic stress meter and the remained pore was analyzed by non destructive X-ray detector and optical microscope. As a result, we showed the trend of sealed area characteristics according to the magnification of PDP panel.

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.

P‐54: Effect of Residual Stress on Mechanical Properties of PDP Glass Substrate

AbstractWe analyze the effects of thermal mismatch caused by the thermal expansion difference between the dielectric layer and the glass substrate on the breakage of PDP panel. The residual stress and the flexural strength of dielectric layer coated glass substrate were measured with the variation of thermal expansion coefficient of dielectric layer by the addition of ceramic filler. The result of strain viewer suggests that the residual strain of glass substrate near the dielectric layer showed the increase of tensile strain and the other side of the glass showed that of compression strain as the thermal expansion coefficient of dielectric layer decreased. The flexural strength of dielectric layer coated a glass substrate was also influenced by the variation of the thermal expansion coefficient of dielectric layer. The result of the analysis has shown that the thermal mismatch caused by the thermal expansion coefficient difference between the dielectric layer and the glass substrate had an effect on the residual stress and strength of glass substrate, although the thickness of dielectric layer was only a few tens of micro‐meter.

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.

P-46: Novel Energy-Recovery-Circuit Integrated into PDP Data-Driver IC

In this paper, the novel driver IC with built-in energy-recovering circuit to provide the energy-recovering capability to each channel of PDP, is proposed. The proposed IC employs the simplified 2-step switching Energy-Recovering-Circuits which do not require the additional inductor component, thereby enabling the simpler design and the reduced cost. The analysis of the system efficiency shows that the employed scheme is the most feasible and valuable solution for PDP driving system because it can be integrated into single IC and each channel can be independently operated. The experimental results of the proposed scheme on PDP Panel show that it can reduce the power consumption in the addressing mode by 30%, if the ERC control logics are properly designed.

32.2 : MgO Protective Layer using Single Crystal Nano-Powder in ac-PDPs

Protective layer of ac-PDPs was fabricated on the dielectrics with single crystal nano-powder MgO(<∼50nm). Nano-powder and vehicle were mixed for 1 hour and milled for 30minutes. And then dispersion solution was coated on PDP panel by bar coating method. Heat treatment of coated film was conducted at 120°C, 10min and 500°C, 30min in order to eliminate the remnants of vehicle and strengthen the endurance of film. Newly developed nano-powder MgO showed high transmittance, endurance and excellent electrical discharge properties. In addition, it had better chemical stability compared with the conventional E-beam MgO, especially in the aspect of water and impurities absorption properties.

DIA-PDP with high luminous efficacy and increased vertical resolution

— A PDP utilizing a new cell configuration to improve the vertical resolution and luminous efficacy is proposed. In this configuration, a delta subpixel arrangement is adopted because it reduces the vertical pixel pitch by half and increases the vertical resolution. In this configuration, R, G, B subpixels form triangles which are diamond shaped, the rational for calling this technology “DIAPDP.” High luminous efficacy is achieved by reducing the reflectivity of the panel. The lower reflectivity enables increased transmittivity of the light-reduction filter which is part of the PDP panel, thus ensuing sufficient contrast under bright conditions. The higher transmittivity increases the luminous efficacy with the filter. Results obtained for a 46-in. panel demonstrate a 33% increase in the luminous efficacy when using the filter. The DIA cell configuration is further modified to be a “clustered DIA” in order to improve the color mixing. Through subjective evaluation, the color mixing was compared with that of panels based on a trio subpixel arrangement and DIA, and the effect on color mixing was confirmed. The luminous efficacy of clustered DIA is also shown to be equal to that of DIA.

A New Method for Measuring the Wall Charge Waveforms of AC PDP

A new method is developed to measure the wall charge waveforms in coplanar alternating current plasma display panel (AC PDP). In the method, two groups of display electrodes are selected from a coplanar AC PDP and two capacitors are respectively connected with these two groups of display electrodes in series, and a measuring circuit and a reference circuit are thus constructed. With the help of special processing, discharge takes place in the cells included in the measuring circuit under a normal drive voltage but no discharge takes place in the cells included in the reference circuit under a normal drive voltage. The wall charge waveforms are obtained from the voltage difference between the two capacitors. Using the method, the wall charge waveforms are measured during resetting period, addressing period and sustaining period for the 304.8 mm (12-inch) test PDP panel. The result shows that the wall voltage is about 96 V during the sustaining period.

141.1: Eu3+ Activated Red Emitting Phosphors for PDP Applications

AbstractRed emitting borate‐based phosphor is currently used in the manufacturing of PDPs as a red component. The color purity of these phosphors is poor due to an orange line in the emission spectrum. Efforts are being made to develop a better phosphor and replace the existing borate phosphor. In this presentation, luminescence characteristics and morphology of red emitting trivalent europium activated rare earth oxide, vanadate, borate, phosphate phosphors and their complexes are presented. The life (stability) of these phosphors in a PDP panel are also presented. The suitability of these phosphors in PDP applications is discussed.

5.1: Invited Paper: High Efficacy PDP

AbstractThe trade‐off between PDP panel efficacy improvement and driving voltages is investigated for several design factors. It is found that for a proper combination of an increased Xecontent, cell design, and the use of a TiO2‐layer combined with “non‐saturating” phosphors, a large increase of both efficacy and luminance can be realized at moderately increased drive voltages. In a 4‐inch color test panel a white efficacy of 4.4 lm/W and a luminance of 5000 cd/m2 is obtained for sustaining at 250 V in addressed conditions.

Characterization of PDP performance prepared by vacuum in‐line sealing technology

By using vacuum in‐line driving and photoluminescence measuring system, we have examined the electrical and optical characteristics of plasma display panel produced by vacuum in‐line sealing technology. In addition, the relationship between luminous efficiency and base vacuum level before filling discharge gas was analyzed. In the case of base vacuum level of 1.33 × 10‐1 Pa, the firing voltage of a 2‐inch diagonal PDP panel was ranged from 312 to 343 V depending on the discharge gas pressure of 2.667 × 104 to 4×104 Pa at room temperature, Whereas in the case of 1.33×10‐4 Pa, the firing voltage was reduced by 40 V and luminescence was improved slightly.

35.2: Development and Characteristics of a 25‐in. XGA PDP Using LTCC‐M Technology

Abstract25″ XGA (165 μm pitch) PDP panel was developed using LTCC‐M (Low Temperature Cofired Ceramic on Metal) technology. Simulations of optimum barrier height and gas composition for maximum power efficiency was carried out and the gas composition was determined to be 71 % He‐25 % Ne‐4 % Xe (in vol %) for the LTCC‐M PDP panel. Some packaging issues including vacuum compatibility of LTCC‐M panel are addressed and the LTCC‐M panel properties are described.