How Television Works Article

LCD Television

Liquid Crystal Display technology or LCD technology for short has been around for many years through displays used in several common daily use devices. Whether it is displaying numbers in calculators, or time in digital clocks and watches, or letters and images in laptops, or setting the time and power in microwaves, or the favorite music number in a CD player all depend on LCD technology even though one may not be aware of its presence. Another gadget using LCD technology that is becoming hugely popular is the LCD television.

LCD televisions use LCD panels for displaying the images – thin and flat devices consisting of a no. of pixels or picture elements that illuminate depending on the signal passed through them. These pixels are made up of thin film transistors (TFT). The TFT is a kind of field effect transistor containing layers of metallic, dielectric and semiconductor material. The LCD technology functions differently from the LED (Light emitting Diodes), plasma or cathode ray tube technology for displaying images.

Early LCD technology had drawbacks like ghost images when images are moving fast, narrow viewing angles that made it hard to view even when positioned slightly away from the monitor, etc. but they have been overcome now. They compare favorably with plasma panel technology and have become very popular. LCD technology is also more energy efficient and less bulky than cathode ray tube televisions. The images are more pleasing and less strenuous to the eyes than CRT based displays. The images are distortion free and are of higher quality than the latter.

The panels can be conveniently mounted on walls thus saving space. The display sizes were small in the early years of development of LCD technology but large size LCD television screens have been recently manufactured by companies like Sony, Sharp, Samsung, LG-Philips, Westinghouse Digital etc. Seventh generation LCD panels as large as 45 inches have been available since October 2004, while even larger sizes like 65 inches have been introduced by Sharp Corporation, 82 inches by Samsung in March 2005 and LG-Philips introduced 100 inches panel in August 2006.

Recent LCD television is adaptable to the variety of display standards that are in vogue around the world today like NTSC, PAL and SECAM. They also have built in electronic transformers to handle various voltages like 110 and 230V, universal adapter plugs etc. The LCD panels apart from TV can be used as computer monitors that work with VGA and DVI signals and have wide variety of resolutions. The market for LCD television is expected to grow considerably in the next few years and the cost is expected to come down with various manufacturers investing heavily for producing these panels.