It tells a story of what must be happening daily in retail land that a discount retail chain, better known for fitting too many products priced at one cent under a round dollar figure on to the page, should choose to take up valuable newspaper ad space explaining how plasma screens work.
Fact is it's bafflingly complex - even for home entertainment specialists - but since a 42-inch plasma TV costs about as much as a second-hand family car, buyers reasonably want to know how that could be so. Expecting a minimum-wage shop assistant to get it right, and still remember which aisle the personal hygiene products are in, is expecting a bit much. Besides, who ever actually knew how standard CRT (cathode ray tube) televisions work?
We are not alone in our bewilderment. Plasma came a hot fourth in research recently undertaken by an American language expert to find the 10 most-confusing - yet widely used - high-tech buzzwords on the internet, in the media and in advertisements.
Plasma screens are actually self-lighting or emissive displays that use a phosphor coating to make pictures, much like good ol' tube TV screens do. Plasma screens are made up of two transparent flat glass panels sandwiching millions of phosphor-coated glass bubbles in a thin layer between them. The bubbles contain a mix of neon and xenon gases. Each bubble, representing one pixel, is composed of three gas-filled cells or sub-pixels (one each for red, green and blue). Each of these million or so individual plasma cells can be switched on and off by its own electrode.
To produce a picture, electric current flows through the screen causing the gas inside the bubbles to ionise (the so-called plasma state) and emit ultraviolet rays. The UV rays then stimulate the bubbles' phosphor coating to produce coloured light. Used in combination, the three basic colours can produce the full rainbow spectrum.
Since you are looking directly at the source of the image (the bubbles) you get a vivid and strong picture. Because plasma screens are illuminated at the sub-pixel level, images can be extremely accurate, and brightness is both high and consistent across the entire screen. Plasma can also offer wide horizontal and vertical viewing angles, meaning the picture looks sharp and bright from virtually anywhere in the room, a big bonus for any home theatre buffs regularly hosting groups of friends and family.
Most of the appeal of plasma televisions comes undoubtedly from their comparatively slim flatness and large screen sizes. The problem lies with the cost and those prices climb exponentially as the screen sizes get bigger. Due to the fragile technology of the screen sandwich, they need to be carefully transported and professionally installed. These are heavy pieces of furniture to be hanging on a plaster wall and unlike the more versatile LCD screens are also power-hungry.
Plasma screen technology has vastly improved over the years, and the serious issue of high cost but limited lifetime seems to have been fixed. Still, do beware, not all plasmas are created equal, as even a quick trip to a specialist store offering a range of brands and models will reveal. You could, after all, buy another car instead with your money - though keeping it filled with petrol may prove financially crippling these days.
<EM>Hot wired:</EM> Plasma TVs can cause a touch of screen envy
AdvertisementAdvertise with NZME.