People are crazy about LED TVs. According to some studies, the demand for LCD screens is still increasing. The range is correspondingly large and the best LED TV manufacturers in India advertise with a variety of buzzwords such as LED TV, Full LED, QLED, and OLED.
At first, that sounds like innovative and modern technology, but the different terms often mean one and the same thing. Many ask themselves what the difference is between LCD and LED or why there are hardly any plasma screens anymore.
This article will provide orientation in the jumble of words, explain how the various LED TV manufacturers in India use television technologies, and discuss their attributes.
Either LED or LCD? Or both?
First of all: All LED screens are also LCD screens. The term LED (light-emitting diode) refers exclusively to the illumination of the image-forming liquid crystal layer of LCD screens. This crystal layer of an LCD (liquid crystal display) cannot light up by itself and must be emitted by an illuminant behind it.
Most people remember this principle from school or university when labeled slides were projected onto the wall using a projector. The LCD TVs without LED backlight are equipped with cold cathode ray lamps, better known as fluorescent tubes. The disadvantage here is usually the poor illumination of the entire screen.
In addition, the tubes are not as durable as LED devices. They begin to flicker after some time in operation, appear through the liquid crystal layer during normal operation, or can fail completely. This results in poor color and black reproduction and the contrast is significantly impaired.
LED is not just LED – Edge LED and Direct LED
New LCD flat screens are illuminated by LEDs. Here, however, attention must be paid to the difference between the so-called Edge LED and the Direct LED (also Full LED).
If the light-emitting diodes are installed at the edges of the screen background in the former, a large LED panel illuminates the liquid crystal layer in the latter. The same problems as with conventional LCDs can also occur with cheaper LCD models with edge LEDs since the entire imaging area cannot be illuminated.
Direct LED, on the other hand, not only offers the possibility of illuminating everything evenly but also of not illuminating parts of the image that are supposed to be black at all. This mode of operation of a Direct LED screen, known as local dimming, enables the image to be contrasted brilliantly.
QLED – the next quantum leap in television technology?
One of the latest achievements in LED technology is offered under the name QLED. QLEDs are so-called quantum dot light-emitting diodes. However, misleadingly, no QLED television with actual QLED technology is currently being sold.
At the moment, the functionality is still the same as with conventional LCDs, but so-called quantum dots are incorporated into the liquid crystal layer of the screens and are backlit with blue LEDs.
These quantum dots emit light themselves, in different colors depending on their size. This creates rich color reproduction and the contrasts are extremely high. The aim of the manufacturers is currently to install the self-illuminating quantum dots in TV sets without LEDs in the back.