HDTV information resource - HD TV plasma television

Light isn't created by the liquid crystals themselves. Instead, a light source (a bulb) behind the panel shines light through the display. A white diffusion panel behind the LCD redirects and scatters the light evenly to ensure a uniform image.

An LCD display consists of two polarizing transparent panels and a liquid crystal solution sandwiched in between. The screen's front layer of glass is etched on the inside surface in a grid pattern to form a template for the layer of liquid crystals, which are rod-shaped molecules that bend light in response to an electric current. The crystals align so that light cannot pass through them. Each crystal acts like a shutter, either allowing light to pass through or blocking the light, and it is the pattern of transparent and dark crystals forms the image.

LCD TVs use the most advanced type of LCD, known as an "active-matrix" LCD. This design is based on thin film transistors (TFT), which are tiny switching transistors and capacitors that are arranged in a matrix on a glass substrate. They work to rapidly switch the LCD's pixels on and off. In a color TV's LCD, each color pixel is created by three sub-pixels with red, green, and blue color filters.

One of the biggest challenges for LCD TV manufacturers has been speeding up the pixel response time, which is how fast an individual pixel's color can change without blurring, to ensure that fast-moving objects don't exhibit motion lag or ghosting. Increasing pixel response time is especially critical for larger-screen LCD's where much of the viewing will be DVD movies and/or HDTV.

Plasma TVs employ thousands of sealed, low-pressure glass chambers filled with a mixture of neon and xenon, behind which are colored phosphors (one red, one blue, and one green) for each chamber. When energized, these chambers of "plasma" emit invisible UV light. The UV light strikes the red, green, and blue phosphors on the back glass of the display, which makes them produce visible light.

Plasma and LCD displays are currently the two most popular choices for HDTV consumers, so based on the experience of Hidefster editors and other ratings and reviews, let's see how these two match up.

Plasma displays are typically in the 32"-63" range. Some manufacturers are developing plasmas over 100", but these models are neither available nor affordable for consumers.

LCD displays are typically in the 12"- 55" range, and like plasmas, much larger models are unavailable and too expensive for most consumers. As of July, 2006, street prices for LCD's in the 40"- 44" range are below those of plasmas of the same size. LCD's are predicted to soon account for the majority of HDTV sales in the 40"- 44" range.

(Check back for Hidefster's ratings and reviews for these plasmas and LCD's.)

Plasmas have a viewing angle of up to 160 degrees, and LCD's have a viewing angle of 175 degrees. It is important to note that neither 160 nor 175 degree angles provide enjoyable TV viewing.

For plasmas, "pixel orbiter" and new technologies have helped plasmas reduce burn-in issues.

LCD's do not suffer from burn-in at all, but they can have issues with stuck pixels or "retained pixel charge," which may produce ghosting.

Plasmas have a half-life (the time it takes for the lamp to fade to half of its original brightness) of 30-60,000 hours, depending on the model.

LCD's have replaceable backlights, but the new light can cost more than replacing the TV altogether.

Plasmas handle and refresh rapid movement in video as well as CRT TV's.

LCD's were originally developed for data display, not video, so LCD's need some improvement in this regard. LCD's with 5-16 millisecond refresh rates show very few noticeable artifacts.

Plasmas tend to be heavy and require additional equipment for wall mounting.

LCD's are lighter, more portable, and cheaper to ship that comparably-sized plasma displays.

Plasmas can be as thin as 3" deep; LCD's can be as thin as 2" deep.

Plasmas are fragile and tricky to ship. Installation is best left to a professional.

LCD's are much more durable and can be installed easily by the consumer.

At higher altitudes, the gas held within each pixel is stressed and must work harder, making high altitudes a potential problem for plasmas. Models that are specially designed for high-altitude performance can be expensive.

LCD's are not at all affected by altitude.

Plasmas report higher levels that LCD's. They are excellent where there is no ambient light; their special glass surfaces reflect ambient light, therefore dulling the image.

LCD's reflect very little light, which helps them maintain levels in even well-lit rooms.

Plasma displays use a lot of energy to light each pixel – even the dark ones.

LCD displays use fluorescent backlighting to produce images and use about 2/3 of the power that plasmas of the same size would use.

Plasmas still have some issues with anti-burn-in tactics and the handling of static symbols. A commercial-version plasma will work best of the application calls for a good amount of computer use.

LCD's display static images with full color detail and no flicker or burn-in. Since the number of pixels per square inch is higher for LCD's than any other HDTV technology, LCD's monitors are especially good at displaying large amounts of data.

LCD flat panel Televisions are considered by most HDTV industry insiders to be the future dominant force in the market place. LCD TV is already your clear best choice for a 32" monitor (television). As the HDTV movement accelerates it is anticipated that LCD televisions will even challenge and possibly overtake plasma televisions in the large screen 50 inch plus market. LCD has signifigant advantages over most technologies.

LCD is superior to CRT (Cathode Ray Tube) televisions in almost every way. Some people believe that CRT is capable of truer black coloring than LCD TV, but this is opinion not fact. LCD black color quality varies by brand and model. LCD TV technology is moving so fast coloring is becoming irrelevant. The facts say that LCD is lighter, smaller, sexier, easier to use, and delivers an all around better viewing and living experience.

Sometime in the near future, digital television will not be a choice. In fact, the FCC or Federal Communications Commission has mandated that all TV broadcasting stations be capable of broadcasting digital television by December 31, 2006. This, however, only pertains to over-the-air transmissions, cable and satellite operators are not under the same directive though many are making the move on their own anyway.

This transition has been likened to the move in the 1960's from black and white TV to color TV.

Along with the FCC's mandate that television stations broadcast digital signals, there will also be mandates in place affecting the production of televisions available to the public.

Not all HDTV's come equipped with a built-in tuner capable of receiving HDTV programming by simply connecting an antenna. Sets with this capability built in are called "integrated," and those that don't are referred to as "HDTV ready" or "HDTV compatible." If you purchase an HDTV without a built in turner, you will need to purchase a separate tuner (or cable or satellite box) that will enable your TV to receive high definition programming. Many LCD screens are not true televisions. These LCD screens are monitors for use with any digital input.

As part of the FCC's tuner mandate, they have identified a "rollout" program in which certain sizes of Tvs must have built in HDTV tuners by certain dates. Following is the schedule:

• March 1, 2005: All TV's 36" or larger; half of all TV's 25" or larger
• March 1, 2006: All TV's 25" or larger
• July 1, 2007: All TV's 13" or larger

HDTV legislation continues and there are discussions that December 31, 2008 could perhaps be the official "switch off" of analog television from the airwaves for good. This would essentially make TV's with older NTSC tuners obsolete as they would be unable to receive over air signals. The move toward HDTV is official and in motion. Consumers are in love with the new technology and the FCC is backing the transition completely.

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