I was recently asked what is the difference between LCD and LED? The answer is: both those and others (LCD and LED) refer to lcd(LCD TVs). Structurally different from LCD TVs only by the way of backlighting the LCD display (or matrix, as it is easier for anyone): instead of lamps, LEDs are used. That's it, the article is over, I'll go for a beer

Okay, okay, there is something to tell about the history of development LCD TVs Let's start with the very definition of the abbreviation: LED TV(short for Light Emitting Diode TeleVision) - LED TV. Actually, to be honest, it looks something like this:

It's really LED or LED screens(panels), you can often see them on the main streets of the city, at football stadiums or concerts. Their main drawback is " grain", which is due to the size of the LEDs. It is not yet possible to make the LED as small as a pixel on a modern LCD matrix, but, from a long distance, this graininess is not noticeable, and the block-modular design allows you to assemble (like from cubes) just huge screens :

However, we are already accustomed to the fact that LED TV- this is something completely different, namely: a TV with a liquid crystal display, the screen backlight of which is carried out by a light-emitting diode (LED) matrix. A term like LED TV was introduced by the corporation Samsung v 2007 year to promote its own line of LCD TVs, the backlighting in which was carried out not by lamps, but by LEDs. If you look purely outwardly - "LED" is thinner than "LCD", but the image quality has become much better

Display backlight types: Edge LED and Direct LED
Let's take a look at the types of LED display backlighting. First of all, it happens direct - Direct LED and end - Edge LED... Want to know more?, Then I recommend reading one more small article: Edge LED and Direct LED.

At Direct Direct LED or back light, LEDs are located over the entire area of ​​the matrix, evenly illuminating it through the diffuser:

The thickness of LED TVs is reduced, but not much compared to LCD TVs, which use lamp backlighting. This is what the matrix looks like with bright white LEDs:

End or side illumination Edge LED has its pros and cons. Let's consider the principle of operation of the matrix end illumination: LEDs are located at the top and bottom, on the sides or along the entire perimeter of the matrix, the light from them, through a special light distributor, falls on the diffuser, and then on the screen

In this picture, you can see why TVs with Backlit Direct LED cannot be as thin as in side lighting: Neither lamps nor LEDs can be pressed close to the diffuser, a distance is required for the diffusion of the light flux Due to the end position, the LEDs do not take up space behind the diffuser, therefore, this design can significantly reduce the thickness of the matrix and the entire TV.

Edge LED backlight more economical (fewer LEDs are used), but it also shines worse (for the same reason) The second serious disadvantage is highlights... With a minimum panel thickness, it is very difficult to obtain an ideal light distribution, a thin diffuser cannot cope with this task, as a result, in the dark areas of the matrix (without a signal, for example), you can observe light spots (glare) that interfere with the comfortable perception of the image from the screen of such a TV

Until now, you and I have talked about static(that is, continuous, constant) backlighting, it's time to move on to considering dynamic The main difference dynamic backlight type from static the fact that the LEDs do not light up constantly, it all depends on the image. The LED matrix is ​​divided into groups, each of which is controllable, thanks to this control, you can adjust the brightness of the LEDs in each group, providing clearer color reproduction and a deep "black color"

The last type of highlighting that we will now look at is dynamic RGB straight and side (end) backlight. With this type of backlighting, LEDs of primary colors are used: red, green and blue, and sometimes also white (for better color rendering)

Diodes can be located "one at a time" or in such assemblies, when light transmitting elements of all primary colors are located in one housing:

Such a matrix is ​​capable not only of "highlighting" various parts of the image with a given brightness, but also of providing "illumination" with the desired color gamut, as a result of which the image is as "correct", clear and beautiful as possible.

Although it "saves" the thickness of the matrix, it does not give such an effect, since it can only "highlight" the general picture (they shine through the matrix for the entire length or width), therefore, it seems to me, it is better to leave this type of lighting for external effects, which perfectly complement the overall picture

Let's summarize:
- LED - thinner, especially when using backlighting, but there is a risk of "flashing"
- LEDs have less power consumption and do not contain mercury (unlike lamps)
- LEDs last longer than lamps (theoretically, time will tell soon)
- in LED TV, the brightness, contrast and clarity of the image are higher than in LCD (more precisely, in an LCD matrix with lamp backlight)
- due to dynamic backlighting, the most correct and rich color reproduction is achieved

In custody:
- with this technology based on the use organic LEDs, such a thing as " backlight", is generally absent, since the diodes of the primary colors that form the image are located directly" on the screen "and shine themselves, in addition, such a TV can be rolled up" into a tube ", but that's another story