So what distinguishes HDTV from standard definition television? Apart from the better visual image quality, the technical reason is that there is a higher resolution for each frame that appears on your television, usually making up between one to two million pixels. Simply stated, there is more information displayed for each frame, in a similar fashion to higher resolution digital cameras.
HDTV’s resolution is similar to that of a blu-ray disc or HD DVD at either 720 (HD ready) or 1080 (full HD) lines, which compares with only 480 or 576 for ‘standard definition’ DVDs and around 240 for older video tape formats.
It is a common misconception that HD TVs are different from LCD or Plasma TVs. HD TV only refers to a resolution and the television must use one of the existing technologies such as LCD or Plasma to display the image. Therefore you can have HD LCD TVs and HD Plasma TVs. Do also remember that older LCD and Plasma TVs will not necessarily have support for HD.
In addition to mainstream flat screen LCD and Plasma technologies, there are new entrants into the game such as OLED which uses organic compounds to create a brighter, more evenly lit, crisper display, although so far these are relatively expensive and only available in comparatively small screen sizes. Look out for the acronyms SED standing for Surface-Conduction Electron-Emitter Display and FED for Field Emission Display coming soon as these technologies are being developed as alternatives for existing HD TVs. Three dimensional television, 3D TV is also emerging and set to become a major part of the landscape in the near future.
So until these new technologies reach the mainstream, should you choose LCD or Plasma for your HD TV? This very much depends on the screen size and the type of material you generally watch. If you need the best colour reproduction then you should probably opt for Plasma as it has better potential colour rendition that of LCD and offers a better contrast ratio by producing darker blacks and brighter whites. Plasma also offers better viewing angles, allowing almost perfect viewing when looking at the image from an extreme angle.
Plasma also boasts a very high refresh rate (number of times the image is refreshed per second), while it is possible with an LCD to have some ghosting as a result of slower refresh rates. Despite all of these apparent advantages for Plasma, LCD TVs do have some benefits: they do not reflect glare anywhere near as much as Plasma, they use far less power and are available in a wider range of sizes, particularly at the smaller end of the scale. It is also worth emphasising that the technologies are convergent with each addressing its own shortcomings so nothing ultimately beats viewing your proposed purchase.
So if you’ve bought yourself an HD TV what should you do to start watching high definition programmes? If you have a blu-ray player and some blu-ray discs then this could be the perfect way to enjoy your television’s image quality. When you’ve run out of discs you could watch one of the HD channels on satellite or cable television, as well as those provided by popular networks. You will also need to ensure that your satellite or cable system is HD.