LCD and LED are two types of televisions derived from the same technology, with only a few differences. LCD stands for liquid crystal display, while LED stands for light emitting diode. LCD TVs have liquid crystal between the display panel, which is activated by the supply of electric current. Molecules of liquid crystal, or pixels, twist as the light pass through it, improving the viewing of objects. These pixels are illuminated by cold cathode fluorescent lamps (CCFL) With LED TVs, light-emitting diodes (LED) are used to provide back-light.There are three types of LEDs: full-array LEDs, edge-lit LEDs and dynamic RGB LEDs.
One of the differences between LCD and LED TVs is contrast and black levels. Contrast ratio in TVs is how well the TV can show high-contrast areas. These high-contrast areas are simply those black-and-white areas in the picture display. A TV that has a good contrast ratio is able to show this difference very well. Normal LCD TVs do not show contrast as well as LED TVs. The reason for this is that when the CCFL back-light of of the LCD dims itself, the black color is not very convincing. LED TVs are basically LCD TVs powered with an LED back-light. This LED back-light has a better contrast ratio because the individual LEDs arrange themselves to an off position in the black or dark parts of the screen, creating a more solid black than LCD TVs. This provides much better clarity in dark scenes.
The LED TVS that use dynamic RGB LED as a back-light offer better color quality than LCD TVs, and even better than LED TVs that use the edge-LED technology. The advantage of using the edge-lit LED technology is that it allows the manufacturers to make the TV extremely thin.
Power Consumption and Cost
LCD TVs consume less power than local dimming LEDs of the same size. However, edge-lit LEDs consume less power than LCDs of the same size. Also, the cost of LCDs is cheaper than that of LEDs of the same size. This is due to the higher cost of the LED lighting system, compared to the cheaper fluorescent CFL lighting system used in LCD.
In fast-paced action videos, such as video games, blurring of motion will occur in LCD TVs due to their slower refresh rate times in comparison to the faster refresh rate of the LED TV. This is because the lag in refresh rates has been resolved in LED TVs.