October 05, 2007
Plasma Televison Overview
Plasma television sets, also known as plasma HDTV displays have been available for several years; however, they are more popular than ever today. The main reason for the recent increase in popularity of plasma televisions is that they used to be very expensive, but now, since a lot of manufacturers are making them, the competition has grown and the cost of the plasma televisions has decreased. Another reason for plasma's increased popularity is the fact that the technology has drastically increased the life of plasma televisions. In the infancy of the plasma televisions, the lifespan was only 30,000 to 40,000 hours. With the multitude of new technologies that have helped to increase the lifespan of plasma televisions, nowadays, the average plasma television life span is just as impressive as the picture.
Unlike the usual television screens, the plasma television screens are real space savers! Models can be hung on walls, or set on special stands that are built for plasma televisions. When switched on, a plasma television can dominate a room, but when switched off it can become an unobtrusive wall hanging. The viewing angle of the plasma television is 160 degrees so it shouldn’t be a problem viewing the television from several locations within the room.
Many newer plasma televisions have a set of high quality speakers attached on both sides of the screen. Although the built in speakers are sufficient enough to meet the needs of most causal television viewers, those that watch a lot of television or those who like the experience television or movies in “full movie theater quality” often prefer to add a home theater surround sound system to their plasma television.
The advertisers often talk about the benefits of having a plasma television at home but what they do not usually mention is what a plasma television really is and the technology behind it.
Plasma television provides a higher resolution than any other type of television monitors. A plasma screen contains literally millions of gas-filled cells (each one acting as a single image pixel) trapped between two pieces of glass. The most expensive and the most powerful plasma televisions can display over 16 million different colors.
A plasma television contains transistor electrodes. Instead of operating as a result of a laser hitting every single pixel like a traditional tube television, a plasma television is built with single transistor electrodes at each pixel. That is the reason why plasmas can be so small in size; you don’t need the massive space behind the television to accommodate an electrode gun. The picture on a plasma television is a result of each pixel varying in intensity to produce a different color, with this happening to every pixel a picture consisting of millions of pixels is produced.
No matter if you’re interested in the technology behind plasma televisions or not, if you’re looking for a high quality television that won’t take up a lot of space, plasma televisions are the way to go!
Posted by HDTV at 08:22 AM | Comments (0)
June 06, 2006
HDTV - Samsung's Line
Samsung is at the pinnacle of home electronics and their line of HDTVs is no exception.
Like most manufacturers the plasma models tend to be more expensive than either LCD or DLP, but prices in all three lines are dropping. That trend is expected to continue for at least another year. Offsetting those price drops are an emphasis on larger screens and higher resolutions. Several 42" plasmas are still available and can - theoretically - display 549 billion colors. 'Theoretically' since the human visual system can't discern that many differences anyway.
The 42" HP-S4253 plasma, for example, sports a 10000:1 contrast ratio. In general, higher is better - though, here again there's a limit to what humans can perceive. Any set within the range of 4000:1 to 10000:1 is likely to offer very black blacks and vivid, realistic colors.
Most of the differences among plasmas, like other types, is size and price but some carry extras. The 50" HP-R5072, for example, comes with an in-built card that (in some cases) makes an external cable box unnecessary.
There are a dozen different models to choose from, ranging from 42" to 63" with several 42" models available. Differences lie mostly in the small details. Some have more input/output slots and ports, some have PC card slots or SD slots, others have more speakers than another. Several offer hidden speakers.
The LCD line is a good option for those wanting to spend a little less and willing to accept a 'smaller' screen in exchange. Sizes range from 32" to 46", with the smallest considered small only in the past few years.
The 46" LN-S4692D offers a great viewing angle, 178 degrees, in a flat-panel display on a swivel stand. Contrast ratio is very good at 5000:1.
Even the smaller 40" LN-S4051D would be enjoyed by gamers using an Xbox. At a contrast ratio of 4000:1 with 8 ms response times, blacks will be great and motion blur undetectable for most content, whether game or TV.
Like any LCD it's important to view from the proper distance. For this size, seven feet would be the minimum recommended.
Whatever size you choose, be sure the model includes a HDMI (High Definition Multimedia Interface) and component ports. Without it, you may be frustrated by the poor picture quality from your DVD player. With it, even 480p DVDs can display an impressive picture quality.
Samsung has a variety of DLP style TVs, ranging from as 'small' as the 50" HL-S5065 to the enormous 71" HL-R7178W. All offer excellent picture quality, though some reviews question Samsung's reliability.
The 71" HL-7178 sports a digital cable ready card and supports 1080p video, which no current Panasonic model does. Even the smaller 56" HL-S5688W offers a great 1080p picture and a 14,400 rpm color wheel to minimize 'rainbow' effects that some DLP models suffer from.
The 'i' stands for interlaced, a technique in which the pixel rows are illuminated every other line, a complete screen 'painted' in two passes. 'p' types make one pass across the screen. While, all other things being equal, 'p' types offer a superior picture, interlaced models are still excellent. Older technology suffered from some flicker with interlacing, but that's largely no longer true.
Many HDTV's are offered in HD-ready types. That indicates the receiver has no in-built HD tuner. That isn't necessarily a deal-killer, since many cable or satellite boxes have tuners that can perform just as well. HD-ready is generally less expensive, all other things being equal.
Prices are affected by screen size, obviously, but also by resolution (720p vs 1080p for example), extras and a host of other factors. Check your favorite price comparison website for details. As with any TV, be sure to view under good lighting conditions before deciding.
Posted by HDTV at 04:12 PM | Comments (0)
June 04, 2006
HDTV - LCD vs Plasma
HDTV - LCD vs Plasma, Pros And More Pros (And a Few Hurdles)
Digital LCD screens first became popular several years ago when they were introduced as lighter, slimmer alternatives to CRT computer monitors. The differences were dramatic. When used to form a HDTV they're even more so.
LCDs produce an image by projecting a light onto a series of 'liquid' crystals sandwiched between glass rectangles. Those crystals can pass or block light as they twist internally. Not really a fluid, the term comes from the fact that the crystals can twist easily when subjected to an electrical current. Varying the voltage changes the amount of twist, which results in more or less of the rear-projected light being blocked.
That curious bit of physics gives LCDs their great advantages and introduces some hurdles for manufactures trying to produce great pictures at affordable prices.
The rectangles making up the screen are arranged in rows of pixels ('picture elements') and are actually composed of three, colored sub-pixels set side-by-side. That close spacing and the precise control of twist allows designers to produce an image with great resolution, accurate color reproduction and astounding clarity.
Since every pixel contains the three colors needed - red, green and blue - to form any perceivable color, LCD sets can produce a very realistic color image. But doing so requires that 'behind-the-scenes' the pixels filter the white fluorescent backlight projected onto them.
That arrangement leads inherently to attractive, bright images that plasma type sets can't quite match. However, as sets age, that backlight can dim or change color, reducing their advantage.
Some sets offer the option of replacing the backlight, but that can be expensive. Current models have good lifetimes, though, and by the time it becomes a problem many will be looking to replace the set with the latest technology.
LCDs retain that bright, clear image better than most plasmas even under varying light conditions. Both types perform well in darkened rooms, but LCDs have a slight advantage under brighter conditions and more room arrangements. Inherently anti-glare, these sets look great in almost anyone's setup.
For several years, plasma dominated the upper reaches of size, while LCD often outperformed in the smaller (13" to 37") range. With improved technology, both types do well, with LCDs now available as large as 65". Though, of course, you pay a premium for the larger size.
During those same years, plasmas held the advantage in viewing angle. The nature of LCD panels makes them lose some contrast and the ability to project deep blacks as the viewer moves to the side. Images can look gray and 'washed-out'. Even colors can shift subtly.
Current sets have reduced that problem to a minimum so that under most viewing conditions it will be unnoticeable. For several years 130 degrees was about the best one could hope for, but 160 degrees or more is common today. That covers a field that would satisfy just about any normal setup.
LCDs offer a wide range of uses. In the morning they may serve as a great looking computer monitor, in the afternoon as a game console and in the evening make a first-rate HDTV set. Older models struggled with motion blur (games and some films or shows require 12-15ms response times to avoid streaking), but current offerings have largely overcome that limitation.
The playing field for LCD and plasma has leveled to a significant extent the last few years. Today, except for the extreme sizes, the choice comes down primarily to price, reliability and that ever elusive 'best picture' quality. Be sure to 'test drive' any set you consider under good lighting conditions with a quality source.
Posted by HDTV at 04:03 PM | Comments (0)
