Stability of discharge series in the plasma display panel

The regularity of the pulsed discharges in the plasma display panel is attributed to processes which automatically damp out perturbations from equilibrium conditions. With rectangular wave excitation, these processes are controlled by the dependence of wall voltage changes during a discharge on the cell voltage at the beginning of a discharge. Conditions for stability and instability are derived for both simple series, in which all discharges are identical, and for more complex series of recurrent discharge sequences, for which the discharges within a sequence need not be identical.     

Charge transport in an AC plasma panel

A transverse voltage applied between a display cellDand a transfer cellTon a standard 60 lines/inch ac plasma panel can simultaneously cause a previously ON cellDto fire and transport a large amount of electrons from cellDtoward cellT. The same transverse voltage combines with the voltage due to transported electrons to produce subsequent discharges which, initiated near cellT, grow rapidly as they propagate along the row toward cellD. A voltage pulse (≃sustain pulse), applied to cellT, will combine with the local row wall voltage to produce another sequence of discharges along the row. These discharges, initiated near cellD, gain intensity as they spread toward cellT. This dynamic process results in a large and controllable charge transfer between the display cellDand the transfer cellT, a key mechanism for shift address display. By reversing the polarity of the transverse voltage, ions also can be transported, but ion transport produces smaller charge transfer.     

Optical write-in for the plasma display panel

Techniques of changing the state of plasma display cells with externally applied light are presented. Optical write-in offers the advantage of high-speed parallel data transfer from a photographic transparency to a plasma display panel. It is established that light incident on a plasma cell causes a photoemission from the inner glass surface. The emitted electrons perturb the wall voltage and cause a change in state. The intensity of light needed to change the state of cells can be reduced, without changing the solid panel materials, by two techniques, Electron avalanches initiated by the photoelectrons can be used to decrease the light needed by a factor of 100. By flashing light during the plasma display cell gas discharge, the intensity of the light can be further reduced.     

Two-frequency drive for AC-refresh plasma display panels

A new drive scheme, with mixed low- and high-frequency drives, has been developed for large-capacity (large number of dots) ac-refresh plasma display panels. Its usefulness for suppressing both firing-voltage increase and luminance-level decrease in a large-capacity panel was confirmed using a practical-size plasma panel. This drive technique can produce a large display panel ( > 400-600 scan lines) with about 50-percent lower power dissipation and higher luminance level than a conventional drive technique. It has been clarified experimentally that these results are due to the sufficient formation of the wall charge at an initial discharge period.     

A gas discharge display for compact desk-top word processors

A flat dc-cyclic, gas discharge panel is described that employs a simple three-layer structure with a priming and a display anode in each cell. The priming anodes act in conjunction with phased cathodes to cause sequential breakdown of cells within a group of cell columns and the short-duration, low-current (and, therefore, low-brightness) discharges so formed serve to prime and select which cells will produce longer, high-current (and, therefore, high-brightness) discharges to the display anodes. The design is not limited to the 80-character/line display reported here; it can be extended to longer displays without the duty cycle or brightness being affected.     

等离子体显示技术

本文详细介绍了等离子体显示技术的基本原理，性能特点，关键技术及彩色显示技术的最近进展。     

A new DC plasma display panel using microbridge structure andhollow cathode discharge

A newly designed dc plasma display panel (PDP) using a microbridge structure and hollow cathode has been proposed, and its characteristics have been measured. This new plasma display panel operates in an abnormal glow in the current range from 0-50 μA at 500 torr, with an effective internal resistance of 800 KΩ. This means that the internal resistance is high enough that a resistor-in-cell structure is not necessary any more for the dc PDP. The luminous efficiency of the hollow cathode discharge is at least five times as great as that of subnormal and normal glow discharges. The lifetime of the display panel is shown to be quite insensitive to gas pressure in the range of 400-1100 torr because the sputtered materials are trapped inside the hollow cathode     

Direct electrical readout from plasma display/memory panels

A technique for extracting stored information from an array of plasma display/memory elements uses a direct electrical detection system that senses the charge flow in selectively excited elements. Electronic drive schemes based on this technique and suitable for realizing readout capability in a large-scale plasma display system are described. The design of specially configured sense amplifiers used in these systems, the nature of the noise signals encountered in these systems, and the results of reliability tests on a 128 × 128 line plasma display system with readout are discussed.     

Spatial distribution of wall charge density in AC plasma display panels

Experimental results are given for the spatial and temporal variation of both the wall charge density and the light intensity along the electrode lines of an ac plasma display panel. The results show that the major part of the luminous spreading is along the cathode line, and it does not accurately reflect the spreading of the wall charge. The wall charge density distribution is approximately symmetrical along both the cathode and anode lines, and it is fairly constant up to about a linewidth away from the edge of the electrode line. A qualitative explanation is proposed for this extended uniformity of the spatial profile of the density of wall charge.     

A real-time curve tracer for the AC plasma display panel

A minicomputer-controlled system is used to automatically measure the wall charge transfer curve of a single cell in an ac plasma display panel. Curves can be plotted on a graphics display as fast as 5/s which allows real-time interaction with the user. The measurement technique is based on the ability to directly measure the wall charge from a single cell. The minicomputer controls the sustain voltage across the cell and obtains the resulting wall charge. It then does the tedious algebra needed to complete the transfer curve. The measured curves show numerous interesting effects. The influence of the state of the neighboring cells can clearly be seen. The duty factor of the sustain waveform has a strong influence on the transfer curve. An effect dependent on sustain frequency is presented that shows a transfer curve region with negative slope. The most interesting effect measured is a hysteresis in the transfer curve, in that a different curve is traced out as the cell goes from off to on than when it goes from on to off.     

Improvement of color temperature using independent control of red, green, blue luminance in AC plasma display panel

This paper presents a new driving scheme for the improvement and flexibility of a color temperature without sacrificing a peak white luminance using an independent control of the red (R), green (G), and blue (B) luminance in an alternating current plasma display panel (AC-PDP). The independent control for the R, G, and B emissions can be achieved by selective application of the various narrow auxiliary pulses to the R, G, and B address electrodes during a sustain-period. The auxiliary pulses can control the luminance levels independently from the R, G, and B cells by forming the fast and efficient plasma or by slight disturbing of the wall charge accumulation. By the application of various auxiliary pulses leading to the simultaneous control of each color's luminance, it is observed that the new driving scheme can improve the color temperature from 5396 K to 10 980 K in a 4-in test panel with almost the same peak white luminance as that of the conventional driving scheme.     

Thermal characteristics of glass-metal composition plasma display panels

Plasma display panels use gas plasma to produce light, with a technique very similar to that used for fluorescent tubes. This is currently the only flat panel technology available for very large flat-panel televisions. A newly developed plasma display panel utilizes a composition of glass, metal and frit glass sealing material, in addition to functional thin and thick film glass-powder-based laminate composites. This paper focuses on this new plasma display technology and discusses its structure and thermal reliability characteristics and challenges.     

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.     

An advanced sustaining technology for plasma display panel using voltage-balancing method

A cost-effective plasma display panel (PDP) sustainer employing current injection method (CIM) for energy recovery is proposed. Using a voltage-balancing technique, driver cost can be reduced by about 20%-30% compared with that of the conventional H-bridge driver by using low-voltage switches. The energy recovery performance can be improved by the current that is built up before the energy recovery operation. This buildup current is utilized to change the polarity of the panel electrode and provides additional variable to determine pulse slopes. Experimental results show that the voltage stress of switches connected in series is identically clamped to sustain voltage during sustain operation and that light is emitted more stably by independent control of the rising and falling slopes using CIM. Therefore, the proposed sustainer is expected to be suitable for a low-cost PDP sustaining driver requiring stable discharge characteristics.     

A new and simple light-pen position-detection technique for interactive plasma-display systems

The plasma panel is a 2-level type of display possessing local memory, high luminance, and selective write-erase capability. There are, however, no convenient inexpensive methods for interacting graphically with material displayed on a panel by means of a hand-held stylus. A simple and potentially low-cost technique has been developed in which a light pen can be used to point at any part, dark or light, of a plasma panel, thus making an economical interactive plasma-display system possible. The technique is based on the ability to selectively address one cell of the panel with a sequence of two interrogating pulses. Therefore, depending on the state of the addressed cell, one or the other interrogating pulse will cause the addressed cell to flash at a time different from all other cells, without altering the state of the addressed cell or disturbing the unselected cells. The light pen is gated to look for these light pulses and their individual Phase in order to establish the location of the light pen and the state of the cell. The operating margins for the interrogating pulses exceed the panel's own write-erase margins, and the additional hardware required beyond the normal panel sustain and select circuitry is negligible.     

Improved 40-inch plasma display for wall-hanging HDTV receiver

A new 40-inch-diagonal color dc plasma display panel (cell pitch: 0.65 mm, 800×1340 cells) with both a resistor-in-cell structure and a phosphor screen on the side wall and bottom of the cell has been developed through the improvement on the large-area panel fabrication technologies. Stable HDTV pictures have been experimentally reproduced on a compact display using the new panel and pulse memory drive circuits. The peak white luminance is 150 cd/m². The lifetime of the 40-inch panel is expected to be over 30,000 hours, judging from the results obtained using a medium-sized panel under the same conditions     

Cost-effective PDP sustaining driver with current injection method

A new plasma display panel (PDP) sustaining driver using the charge pump technique is proposed. Since this circuit enables low voltage switches to be usable, the cost can be reduced by about 30-40% compared with that of a conventional driver. To recover energy stored in the panel capacitance, a new energy recovery concept of current injection method is adopted to achieve zero-voltage-switching and reduce electromagnetic interference by rejecting the surge current caused by hard switching.     

Digital Video: A Buffer-Controlled Dither Processor for Animated Images

A new technique has been discovered which permits pseudo-gray tone video images to be played in real-time on bilevel, memory displays such as the ac plasma panel. The technique combines ordered dither processing, selective updating, and hysteretic thresholding to digitally transmit or store the video images. Only a 1 bit/pel frame memory plus a 0.3 bits/pel replenishment buffer are required. This technique makes possible the use of a single terminal to display both graphic-alphanumeric information as well as pseudo-gray tone video images.     

Display-device research and development in Japan

Current work on display devices in Japan is surveyed. Work on plasma display panels includes several methods for producing gray scale on ac-driven bistable panels, a technique for moving the display on an ac-driven panel, and new types of plasma display panels. Development on several types of alphanumeric displays, including both new and older types, is summarized. Work on light-emitting diodes includes new fabrication techniques and new types of devices. The liquid-crystal work described includes addressing techniques, color modulators, and light-addressed light valves. A new cathodochromic display tube, a high-frequency oscilloscope tube, and an electroluminescent display panel are mentioned.