Index
How Does a Plasma Display Work?
What is Life Expectancy of a Plasma TV
How do I input a television signal to a plasma screen display?
Will Plasma TVs become outdated soon?
Why a Plasma TV is the Right Choice.
How does a plasma display work ?
The plasma panel is composed of two sheets of glass with a series of ribs ( like corrugated cardboard ) filled with color phosphors in between. The top glass with embedded electrodes seals and forms a pixel where the junctions of the channels and the plate come together. Inside the sealed pixel, is a mixture of rare gases- typically argon and neon, although xenon has also been used.
Actually a small electric capacitor has been created, with one electrode on the rear and a pair on the front. These 3 electrodes control the capacitor charge, sustain and discharge functions intrinsic to the plasma imaging process.
The plasma imaging cycle can be broken into following steps. initially, the pixel is at its resting ( ie. Off ) state. while a voltage is applied to the addressing electrodes ( pixel ). When the applied voltage reaches a certain level- say 200+ volts - the resistance in the pixel is overcome, and an electrical discharge is made across the electrodes. Once this discharge occurrs, the mixture of rare gases is ionized into a plasma state, which means the gas mixture can now conduct electricity, an intense burst of ultraviolet ( UV ) light is emitted. This burst of UV energy stimulates the color phosphors, in turn makes them glow brightly.
Once the pixel is switched On, a much lower voltage sustains the UV emissions and keeps the phosphors glowing. This sustain voltage is typically in the 50 volts range. Eventually, the pixel will need to be turned off to rest the phosphors. This is done by removing the sustain voltage first, then reversing the charge in the pixel through the addressing electrodes. At this point, the pixel is back to its resting
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What is Life Expectancy of a Plasma TV?
There has been much discussion recently about the life expectancy of plasma monitor/TVs. It is an interesting topic with many misconceptions and story variations. The following is what I can advise on the topic:
Misconception #1: Many retailers seem to be telling consumers that plasma monitors will only last a couple of years which is false as you will see below.
Misconception #2: The gas plasma inside the plasma TV can be refilled or replaced when it burns out. This is false.
So how long will a plasma last? The long and short of it is that it depends upon your daily hourly usage as well as how you use the monitor. 12 to 17 years is my short answer.
Manufacturer’s figures for longevity are vary by manufacturer but they all fall in the range of 20,000 to 30,000hrs.
For consumer use these numbers should be comforting. Plasma Displays are now about equivalent in longevity to CRTs, which typically state 25,000 hours or so life. Let's put these hours in perspective. The average U.S. household watches 4 to 6 hours of television per day. Taking a mean time manufacturer stated longevity of 22,500 hours of usage, times our average 5 hours per day we come up with over 12 years of usage. And that is on the low side of estimates. At 4 hours per day and 25,000 hours we are looking at 17 years.
Now, there are varying degrees of phosphor ignition along the way (the same way a CRT fades). Dissipation begins the moment you turn the set on. After 1000 hours of usage a plasma monitor should measure around 94% brightness, which is barely noticeable to the naked eye. At 15,000 to 20,000 hours the monitor should measure around 68% brightness or to say it differently, 68% of the phosphors are being ignited.
There are steps you can take to ensure longer and better life from your plasma display panel.
1) Never leave static images on the unit. Do not pause a picture on the plasma for more than a minute. This will cause phosphor burn in. Watch the unit in full widescreen format as much as possible to avoid differentiation between the side bands of the unit. While this does not actually decrease the longevity of the phosphors it does cause an annoyance to have to play a gray static image to "erase" the burn in.
2) Use Brightness and Contrast levels that are necessary for viewing - not excessive. In a brightly lit room you may need to use more contrast and brightness, which will decrease the life of the unit. However, there are memory setting adjustments available on most recent plasma monitors that allow the user to choose a memory setting to suit viewing needs. At night, or in a lower light room use lower contrast and brightness levels and extend the life.
3) Keep the monitor/TV in a well-ventilated area. The unit will not have to work as hard to cool itself.
4) Turn the unit off when not in use.
5) Keep the unit out of reach of small children.
6) Do not mount the unit face down from the ceiling. (Philips are you listening?)
How do the manufacturers know how to calculate the figures since plasma monitors have not been out long? The manufacturer facilities in Japan test plasma panels at 100% white image light and measure down from that point with meter readings. It takes hours to find that 50% mark - between 30,000 and 50,000 hours.
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How do I input a television signal to a plasma screen display?
Only a few Plasma monitors come with built in tuners. For most Plasma TV Monitors an NTSC/ATSC television signal must be passed through a satellite box, cable box, HDTV receiver, VCR/VHS device, or an outboard tuning device. Most of these components offer an RF style cable input (what we think of as a cable connection). Signals are then passed to the plasma TV using the following connections:
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From a satellite box an s-video cable is normally utilized.
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From a cable box a composite RCA to RCA or RCA to BNC connection is used.
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From an HDTV decoder box a 15 pin VGA to 15 pin VGA cable is normally used; though 3 cable component RCA to component RCA or BNC is also often an option.
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From a VCR/VHS an RCA to RCA or BNC is normally used though S-video is better option if available on the VCR.
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Optional decoders will have a mix of the above options.
Will Plasma TVs become outdated soon?
Absolutely not, Plasma TVs are ready for the future. Whether it be DVD, HDTV, Digital TV, or a digital satellite receiver, the Plasma TV is the perfect display companion. The dramatic, high-impact picture makes it not only compatible but a very wise choice of television viewing.
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Why a Plasma TV is the Right Choice.
Digital television is now a reality-- but you're not going to see it the way it was meant to be seen using yesterday's TV sets. Today, we're in the midst of a digital video revolution, thanks to HDTV, DTV, DVD-Video, digital satellite broadcasts and computer video. Plasma display technology is the only way to fully enjoy the dramatically improved image quality of all these digital video sources.
Higher resolution
Plasma display devices have higher resolution than conventional TV sets, and are capable of displaying full HDTV and DTV signals as well as XGA, SVGA and VGA signals from a computer. For example, you can get plasma displays with a 1024 x 1024 pixel high-resolution that can display images at true 1080i and 720p HDTV resolution, as well as 480i and 480p HD signals.
No scan lines
Conventional CRTs use an electron beam to scan the picture tube from top to bottom at regular intervals, lighting the phosphors to create the image. In the case of standard (NTSC) TV, visible scan lines can be seen.
Most plasma displays include built-in line doubling to further improve image quality when viewing standard analog video sources such as TV broadcasts and VCR tapes.
Exceptional color accuracy
High-end plasma displays are capable of displaying 16.77 million colors -- providing superb color realism with exceptionally subtle gradations between colors.
Widescreen aspect ratio
Plasma display devices have a widescreen 16:9 aspect ratio, the relationship between the screen's width and height. This is the proper aspect ratio for HDTV, and also allows many DVD-Video movies to be viewed in widescreen format, as originally seen in the theater.
Perfectly flat screen
Plasma display monitors have screens that are perfectly flat, with no curvature whatsoever. This eliminates the edge distortion that can occur in CRT displays.
Uniform screen brightness
Unlike some rear and front projection televisions that suffer from uneven screen brightness -- seen as "hot spots" in the middle of the screen or a darkening near the edges and especially corners -- plasma displays illuminate all pixels evenly across the screen.
Slim, space-saving design
Plasma display monitors are only a few inches thin-providing installation options never before possible. In addition to stand mounting, they can be hung on a wall or from a ceiling, allowing you to enjoy big-screen home theater impact from a component that doesn't dominate floor space. Conventional TVs and front projectors, by comparison take up far more real estate and are much more limited in placement flexibility.
Plasma monitors have an elegant, understated "picture frame" appearance that blends inconspicuously with any dˇcor; with a chassis not much wider than the display screen itself.
Because they eliminate the need for a front projection unit and a projection screen, plasma display monitors are also ideal for use in a wide variety of business and commercial applications where the use of a front projector would not be feasible.
Wide viewing angle
Plasma displays offer a viewing angle of 160 degrees (top to bottom and left to right) -- much better than rear projection TVs and LCD displays. This allows a larger number of viewers to enjoy proper image reproduction from a wider variety of locations throughout the room.
Universal display capability
Most plasma monitors can accept any video format formats. Typically, they will include composite video (NTSC, PAL SECAM) (standard RCA jacks), S-video and component video inputs, plus one or more RGB inputs to accept the video output from a computer.
Whether you want to view a sporting event on HDTV, a DVD-Video movie, a satellite broadcast or even surf the Internet with incredible big screen impact, chances are a plasma monitor will accommodate your needs.
Immunity from magnetic fields
Because plasma displays do not use electron beams, as conventional CRT displays do, they are immune to the effects of magnetic fields. Components such as loudspeakers that contain strong magnets can distort the picture if placed too close a standard TV (which has a CRT). On the other hand, plasma displays can be placed in close proximity to any type of loudspeaker and not experience image distortion.
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Plasma Display Tecnology PDF Spec Sheet by NEC