PLASMA DISPLAY
SEMINAR REPORT ON PLASMA DISPLAY Submitted By SWAPNIL S. BIRHADE Roll No::10207 Guided by Prof.SWAPNILA CHUMBLE Lecturer, IT
DEPARTMENT OF INFORMATION TECHNOLOGY DR.D.Y.PATIL COLLEGE OF ENGINEERING,AKURDI
PUNE- 410 506. 20010 - 11
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PLASMA DISPLAY
DR.D.Y.PATIL COLLEGE OF ENGINEERING AKURDI PUNE-410 506.
DEPARTMENT OF INFORMATION TECHNOLOGY
CERTIFICATE
This is to certify that student Mr.SWAPNIL S. BIRHADE is studying in TE IT course in SEM II and He has successfully
I, entitled “ PLASMA the seminar- I,
completed and submitted
DISPLAY ”. ”.
This study study is is a partial fulfillment fulfillment of the degree of
Bachelors of Engineering in
Information Technology of PUNE
University, PUNE during the academic year 2010-2011.
Date: Place:
(Prof.Swapnila Chumble) Guide
(Prof. K.N.Honwadkar) Head of the Department 2
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ACKNOWLEDGEMENT
With immense pleasure, I am presenting this seminar report as part of the curriculum of T.E. Information Technology. We express our profound thanks to our respected Pricncipal Mrs Alka kote and Head of the Department, Prof. K.N.Honwadkar
whose advice and valuable guidance helped us in making this project interesting and successful one. We are grateful to our guide Prof.Swapnila chumble for his support and guidance throughout the course of our project. We also thanks all those who have directly or indirectly guided and helped us in preparation of this project.
Swapnil S. Birhade Roll No::10207
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CONTENTS
1. Abstract
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2. Introduction
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3. Plasma Display
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4. Cell Structure of Plasma Display Panel
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5. How Plasma Technology works
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6. Schematic illustration of single Cell / Pixel in PD
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7. Plasma Screens and Display
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8. Compare between PDP and LCD
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9. Plasma Advantages and Disadvantages
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10.Conclusion
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11.Bibliography
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Abstract
Plasma displays are bright (1,000 lux or higher for the module), have a wide color gamut, and can be produced in fairly large sizes — up to 150 inches (3.8 m) diagonally. They have a very low-luminance "dark-room" black level compared to the lighter grey of the un illuminated parts of an LCD screen (i.e. the blacks are blacker on plasmas and greyer on LCDs). LED-backlit LCD televisions have been developed to reduce this distinction. The display panel itself is about 6 cm (2.5 inches) thick, generally allowing the device's total thickness (including electronics) to be less than 10 cm (4 inches). Plasma displays use as much power per square meter as a CRT or an AMLCD television. Power consumption varies greatly with picture content, with bright scenes drawing significantly more power than darker ones - this is also true of CRTs. Typical power consumption is 400 watts for a 50-inch (127 cm) screen. 200 to 310 watts for a 50-inch (127 cm) display when set to cinema mode. Most screens are set to 'shop' mode by default, which draws at least twice the power (around 500-700 watts) of a 'home' setting of less extreme brightness. Panasonic has greatly reduced power consumption ("1/3 of 2007 models") Panasonic claims that PDPs will
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consume only half the power of their previous series of plasma sets to achieve the same overall brightness for a given display size. The lifetime of the latest generation of plasma displays is estimated at 100,000 hours of actual display time, or 27 years at 10 hours per day. This is the estimated time over which maximum picture brightness degrades to half the original value.
Nature of Plasma
Plasma TV
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INTRODUCTION
As the flat panel television category continues its explosive growth, plasma display panel (PDP)technology remains the benchmark and de facto standard that consumers seek when considering the purchase of flat
panel home theater display devices. To many consumers, the term
―plasma‖ has become synonymous with all flat panel displays – even though liquid crystal display (LCD) products are also available. Until recently, the market for direct-view, flat panel televisions was segmented fairly clearly, with LCD sets available only in screen sizes smaller than 30 inches, and PDP products available in larger screen sizes ranging from 42 to 61 inches. Today, the consumer market for these two flat panel technologies is beginning to converge, due to mass production of LCDs in larger screen sizes. While PDP and LCD offer some shared benefits (their flat, thin form factor and undistorted, fixed-pixel image rendering), significant quality differences remain. Plasma displays continue to best fill the needs of
home theater enthusiasts seeking premium-quality large-screen display devices, due to several inherent benefits of the technology.
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Plasma Display
A plasma display is a computer video display in which each pixel on the screen is illuminated by a tiny bit of plasma or charged gas, somewhat like a tiny neon light. Plasma displays are thinner than cathode ray tube ( CRT ) displays and brighter than liquid crystal displays ( LCD ). Plasma displays are sometimes marketed as "thin-panel" displays and can be used to display either analog video signals or display modes digital computer input. In addition to the advantage of slimness, a plasma display is flat rather than slightly curved as a CRT display is and therefore free of distortion on the edges of the screen. Unlike many LCD displays, a plasma display offers a very wide viewing angle. Plasma displays come in conventional PC displays sizes and also in sizes up to 60 inches for home theater and high definition television .
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Plasma Display
Cell Structure of Plasma Display Panel The plasma display itself is a simple device consisting of two parallel glass plates separated by a precise spacing of some tenths of a millimeter and sealed around the edges. The space between the plates is filled with a mixture of rare gases at a pressure somewhat less than one atmosphere. Parallel stripes of transparent conducting material with a width of about a tenth of a millimeter are deposited on each plate, with the stripes on
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one plate perpendicular to those on the other. These stripes are the "electrodes" to which voltages are applied. The intersections of the rows of electrodes on one side and the columns of electrodes on the opposite glass plate define the individual color elements – or cells – of a PDP. For high quality color images it is important to keep the UV radiation from passing between cells. To isolate the individual cells barriers are created on the inside surface of one of the plates before sealing. Troughs, honeycomb-like structures and other shapes have been used. The red, green and blue phosphors are deposited inside these structures. A commercial panel consists of several million cells which have to be switched at a rate that will create 60 TV picture frames per second. A computer translates an image into a sequence of On and Off voltage pulses which are applied to the electrode arrays line by line and row by row to select individual cells. Such control is possible because the plasma is fast and can respond to the voltage pulses in a millionth of a second. The complexity increases significantly when we consider that each small picture element, or pixel, consists of three color cells, and each color cell can display 256 intensity levels. Thus each pixel can display over 16.7 million (or, more exactly, 256x256x256) colors. 10
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Plasma glass plate and pixel
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How Plasma Technology works Plasma TV's create a picture from a gas (plasma) filled with xenon and neon atoms and millions of electrically charged atoms and electrons, that collide when you turn the power on. The collision increases the energy level in the plasma and the neon and xenon release photons of light (similar to the way neon lights work). PLASMA display panels (PDPs) are one of the leading candidates in the competition for large-size, high-brightness flat panel displays, suitable for high-definition television (HDTV) monitors , Their advantages are high resolution, fast response, wide viewing angle, low weight, and 12
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simple manufacturing process for fabrication. The fact that they are expected to be the next generation of TV displays is evident in the remarkable recent progress of PDP technology development and manufacturing ,One of the most critical issues in PDP research and technology development is the improvement of luminance and luminous efficiency , which is dependent on the gas mixture composition, phosphor efficiency, driving voltage characteristics, and cell geometry. PDP cells can operate only if the applied voltage is held within certain limits. The minimum and maximum values of the applied voltage define the margin of the panel . These limits are determined by the breakdown voltage. In some PDP designs, reducing the breakdown voltage may be of higher priority than is increasing the efficiency, because of the high cost of high-voltage driving circuits . In this article, we focus our attention on the effects of gas mixture composition on light generation efficiency and on the breakdown voltage. Typical plasma displays consist of two glass plates, each with parallel electrodes deposited on their surfaces. The electrodes are covered with a dielectric film. The plates are sealed together with their electrodes at right angles, and the gap between the plates is filled with an inert gas mixture. A protective MgO layer is deposited above the dielectric film. The role of this layer is 13
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to decrease the breakdown voltage caused by the high secondary electron emission coefficient of MgO. The discharge is initiated by applying a voltage pulse to the electrodes. Xenon gas mixtures are used to efficiently generate UV photons. The UV photons emitted by the discharge hit the phosphors deposited on the walls of the PDP cell and
are converted into visible photons. Each cell contains phosphor that emits one primary color — red, green, or blue. In this paper, we study different Xenon gas mixtures and theoretically investigate their efficiency in generating UV photons. In particular, we examine three different cases, i.e., Ne – Xe, He – Xe, and Ne – Xe – Ar. In each case, we investigate the effect of the variation of the percentage of the constituent gases on the efficiency of the mixture and on the breakdown voltage.
All plasmas require a source of energy. As in fluorescent lamps, the plasma in a PDP is produced by applying a voltage across a gap that contains gas. The plasmas used in PDPs are considered "cold" plasmas in the sense that the background gas stays relatively cold while the electrons (and ions) in the plasma are heated by the applied voltage. When the hot electrons collide with the background gas atoms and
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transfer energy to them, many of those atoms respond by emitting UV radiation. The operating conditions of the display (gas composition, pressure, voltage, geometry, etc.) represent a compromise, taking into account performance requirements such as low voltage operation, long life, high brightness and high contrast. The plasma display itself is a simple device consisting of two parallel glass plates separated by a precise spacing of some tenths of a millimeter and sealed around the edges. The space between the plates is filled with a mixture of rare gases at a pressure somewhat less than one atmosphere. Parallel stripes of transparent conducting material with a width of about a tenth of a millimeter are deposited on each plate, with the stripes on one plate perpendicular to those on the other. These stripes are the "electrodes" to which voltages are applied.
Brightness and Contrast Ratio In the spec wars, Brightness and Contrast Ratio seem to be the most important numbers for both consumers and manufacturers. Unfortunately, both of these specs are significantly misunderstood as well as significantly abused and exaggerated. The values published by most manufacturers are now so outrageous that they are close to absolute
nonsense, and it’s getting worse. Throughout this series we have measured the Brightness and Contrast 15
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values using a consistent and scientifically objective procedure. See earlier articles for an in-depth discussion and explanation. Briefly, here is their significance: you need to have a sufficient amount of brightness for comfortable viewing in your ambient light viewing conditions, but after that more is not better, in fact, for some display technologies it is actually worse. Contrast Ratio is affected primarily by how dark and close to black the screen can get, but that is only important under low ambient lighting conditions. Note that it is only possible to obtain high picture quality and accuracy under low ambient lighting. In that case you need moderate brightness and a high Contrast Ratio. For high ambient lighting, you need high brightness, but don’t worry about picture quality or accuracy or Contrast Ratio, because they are all irrelevant under these viewing conditions.
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Schematic illustration of single Cell / Pixel in PDPs
Plasma Screens and Display 17
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Compare between PDP and LCD
Attribute
Plasmavision Display
TFT LCD
Plasmavision Benefits
Sizes available in mass production .
Big screens! 42‖ to 63‖
Small 12‖ to medium 37‖
Peak brightness level
Very good
Good
The home theater experience demands a big screen, seen from a comfortable viewing distance. Plasmavision offers large screen sizes Plasmavision displays deliver the visual ―punch‖ home theater enthusiasts demand.
Contrast ratio
Best
Good
Contrast is an essential measure of quality in home theater displays, and Plasmavision delivers superior results.
Color fidelity
Excellent
Limited
Plasmavision displays use a broader color spectrum, to deliver accurate color fidelity as seen on the best direct-view CRTs.
40 to 70
Everyone can
Viewing angle, full 160 to 180
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color and brightness (degrees)
Non-failure of individual pixels
enjoy a Plasmavision monitor’s excellent color and brightness from every part of the room. Excellent
Individual pixels can fail over time
Plasma Advantages and Disadvantages
Plasma Advantages Excellent (real) contrast ratios and black levels Excellent color reproduction Excellent life expectancy Excellent viewing angle with no real loss of color or contrast
Plasma Disadvantages Cost is very high as compare to LCD
More Electric voltage is required as compare to LCD 20
Plasmavision’s pixels keep working – individual pixel failure after installation is extremely rare.
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Conclusion We see this more and more on store signs and in ads promoting largescreen, flat-panel plasma TVs. The flat plasma display is a major competitor among several flat panel display technologies – all vying for the potentially enormous High Definition TV market.
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Bibliography Site Address www.plasmacoalition.org www.panasonic.com
www.google.com
www.associatedcontent.com
www.members.tripod.com
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