LCD stands for “liquid crystal display” and technically, both LED and LCD TVs are liquid crystal displays. The basic technology is the same in that both television types have two layers of polarized glass through which the liquid crystals both block and pass light. So really, LED TVs are a subset of LCD TVs.
LED, which stands for “light emitting diodes,” differs from general LCD TVs in that LCDs use fluorescent lights while LEDs use those light emitting diodes. Also, the placement of the lights on an LED TV can differ. The fluorescent lights in an LCD TV are always behind the screen. On an LED TV, the light emitting diodes can be placed either behind the screen or around its edges. The difference in lights and in lighting placement has generally meant that LED TVs can be thinner than LCDs, although this is starting to change. It has also meant that LED TVs run with greater energy efficiency and can provide a clearer, better picture than the general LCD TVs.
The LCD television is a flat-panel television which utilizes a Liquid Crystal Display technology. It has two layers of glass which are polarized and stuck together. The liquid crystals are held in one of the layers. These liquid crystals pass, or block the light, to produce images on the screen when the electric current passes through it.
However, the crystals do not produce their own light. The light comes from the series of fluorescent lamps at the back of the screen. There are millions of shutters arranged in a grid, which open and close to release and trap some of the light that is not needed to create images. Then each shutter is paired with a colored filter which produces a sub-pixel. These are so small, that when they combine, they create a single pixel, which appears to be a single spot of color on the screen. With the help of the fluorescent lamps, the images created by the liquid crystals become visible to the viewer.
LED TV’s are actually very much like LCD TV’s. They also have a flat-screen which utilizes Liquid Crystal Display technology. The only difference is their source of light, which is at the back of the screen. The LCD TV uses fluorescent lamps, and the LED TV uses LED (Light Emitting Diodes).
LED TVs provide a better picture for two basic reasons. First, LED TVs work with a color wheel or distinct RGB-colored lights (red, green, blue) to produce more realistic and sharper colors. Second, light emitting diodes can be dimmed. The dimming capability on the back lighting in an LED TV allows the picture to display with a truer black by darkening the lights and blocking more light from passing through the panel. This capability is not present on edge-lit LED TVs; however, edge-lit LED TVs can display a truer white than the fluorescent LED TVs.
Because all these LCD TVs are thin-screen, each has particular angle-viewing and anti-glare issues. The backlit TVs provide better, cleaner angle viewing than the edge-lit LED TV. However, the backlit LED TV will usually have better angle viewing than the standard LCD TV. Both LED and LCD TVs have good reputations for their playback and gaming quality.
There are two types of LED backlighting. One is referred to as Edge lighting, and the other is called Full-Array lighting. With the Edge lighting, the series of diodes are arranged along the outside edges of the screen. When there is power, the light is distributed across the screen. Alternatively, in Full-Array lighting, there are several rows of diodes behind the entire surface of the screen. They provide more control over brightness and dimming, because the diodes can be turned on and off independently.
LED TV’s are LCD TV’s with a new backlight system. They are newly developed for LCD’s, because Light Emitting Diodes are said to give more balance in color saturation, and use less power than the fluorescent lamps. LED TV’s are the newest version, and that’s why they are currently more expensive than the standard LCD TV’s.
LED TV’s are still LCD TV’s. They are just considered to be the newer LCD TV version because of the new backlight system used. The LED TV uses Light Emitting Diodes, while the standard LCD TV uses fluorescent lamps. Although they both still use Liquid Crystal Display technology. The main difference is the part behind their screen, which is the backlight.