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LED TV – General Information

There is much confusion regarding what an “LED TV” is and what the benefits of LED TVs are over traditional LCD TVs.

What is LCD Technology?

It is important to clarify what an “LCD TV” actually is. An LCD is a thin, flat panel used for electronically displaying information. It is an optical device made up of tiny liquid crystal 'dots' that constitute sub-pixels. A pixel is made up of 3 different coloured sub-pixels (red, green, blue) which when combined are capable of producing a colour spectrum. The pixels are arranged in an array and together they are capable of producing an image.

LCD Technology has been in widespread use since the early 1970s, initially appearing in Digital Watches. In the last decade it has become increasingly popular and today is the main technology used in Televisions worldwide.

The backlight of an LCD TV illuminates the coloured pixels from the side or back of the display panel so that their colour can be seen. There are different types of backlight technology available. Currently most LCD devices implement what is called a Cold Cathode Fluorescent Lamp (CCFL) as their backlight. This is very much like fluorescent lighting with the difference being that CCFLs do not need the long flickering startup time that fluorescent lighting does, as they are able to start cold. CCFLs do still need a high voltage to operate though, and even though they start cold, they can still get quite warm. Earlier LCD TV Models had trouble creating deep blacks as the fluorescent tubes are always on and thus some light leaks through to the front of the display even when a part of the image is supposed to be black. A lack of deep blacks can reduce the perceived sharpness of the TV's image.

What is LED Technology?

There is a new backlight technology that is becoming available that uses Light Emitting Diodes (LEDs) for the backlighting requirements. There are numerous advantages to this technology over CCFLs, but the most prominent upon first seeing a device with this technology is that the device is likely to be significantly thinner than its CCLF powered counterparts. This is due to the fact that LED powered backlights do not need bulky fluorescent tubes. LEDs are also powered by standard low voltage electronics and are much more efficient at producing light than CCFLs are. This leads to a brighter image and better power efficiency.

More advanced LED Televisions also have improved contrast ratios as specific areas of darkness on the screen can be improved by using local dimming. This results in higher contrast ratios between different regions of the screen.
This new backlight technology is where the new LED TVs get their name. Technically they should be called LED-LCD TVs (as opposed to CCFL-LCD TVs) but many manufacturers simply refer to them as LED TVs for simplicity's sake.

The future of LED Technology - OLED

Research is currently being done at LCD Panel manufacturers on an even-more exciting technology which promises to revolutionise the type of Televisions we see today. This technology is based on Organic Light Emitting Diodes (OLED). This new technology replaces the need for a backlight all-together as each pixel produces its own light.  Such displays have the potential to revolutionalise the application of LCD Technology allowing for newer applications and thinner and more flexible displays in the future. This technology is still in development with early prototypes available. Industry projections are that these televisions will be commonplace in the next 3-5 years.

LED VS LCD TVs - Buying Guide

When buying your next television it is important to decide the type of technology you want your TV to use. Both LED and traditional LCD TVs have benefits and this must be weighed up against feature set and price of any unit.

LED Televisions are generally thinner, more energy efficient and offer superior contrast to traditional LCD Televisions. However, LCD Televisions using a CCFL backlight are becoming increasingly thinner and more energy efficient. The technology has also had time to mature and thus contrast levels are becoming better.

The average customer might not notice any difference in picture quality amongst such televisions. It thus comes down to the connectivity and feature set of each television and the price. It is important to look for televisions with Built-in HD Tuner, HD Resolution and HDMI ports to connect to other high definition devices. In terms of price LCD TVs are much cheaper than LED TVs however prices are continually falling.

For More information please visit: http://en.wikipedia.org/wiki/LED_TV

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