Ice TV what is it? What is LED backlighting? Backlight types

In 2016, the development of television technology brought LED-backlit TVs to the peak of popularity; they are called “ice TVs.” Also today in stores you will find television receivers with OLED-based screens.

LED TVs are television receivers in which the screen is built on a liquid crystal matrix (LCD) backlit by LEDs.

The liquid crystal matrix is ​​abbreviated in English as “LCD” (liquid crystal display). And previously, devices with such screens were called LCD TVs. But for the liquid crystal screen to work, it needs a backlight, and for the first few years a CCFL fluorescent lamp was used for backlighting. Then light-emitting diodes (LEDs) began to be used to operate the backlight. And now TVs with liquid crystal displays are called “LED TVs”, which is the same as “LCD TVs”. The differences in these names are only in the form of backlighting; all other parameters and operating principles remain the same.

As of 2014, all companies stopped producing LCD TVs backlit by a fluorescent lamp. Models are available with liquid crystal screens and LED backlighting. And today such television receivers constitute the most widespread and affordable segment of televisions. Plasma models are already leaving the market, there are only a few companies left that continue production plasma TVs and these are just a few new models in 2014, and these are not flagship models. But devices with OLED screens (screens based on light-emitting diodes) belong precisely to flagship models, and their price does not yet allow these TVs to be transferred to the mass category.

Differences between LED and conventional LCD

When using lamps to backlight the matrices, it was impossible to adjust the backlight of individual areas of the screen. This led to the fact that the contrast of LCD screens was not high enough to compete with plasma or even picture tubes that were still alive at that time. Therefore, we came to the decision to use LEDs to illuminate the matrix. At the same time, it became possible to adjust the backlight in individual areas by adjusting the brightness of individual LEDs.

This is where we get advantages LED backlight Compared to a conventional fluorescent lamp:

• improved screen brightness,
• contrast,
• color rendering,
• and energy consumption has decreased by up to 40%.

Due to the small size of the LEDs and the overall thickness of the LED TV body, it is smaller than others.

Differences in backlighting between CCFL and LED

LED lighting methods

There are two types of LED backlight: side and back. Side (Edge) lighting, in which LEDs are located around the perimeter of the TV body. Backlight (Direct) illumination, in which the LEDs are located evenly behind the matrix. top scores The image quality is provided by Direct backlighting with the ability to locally dim groups of LEDs. Edge backlighting is cheaper, so it is more used in TV production

How the backlight works

The main problem of LCD screens was contrast, or rather its low value. Contrast is the ratio of the brightness in the brightest area of ​​the screen to the brightness in the darkest area. Screen manufacturers have tried to adjust the backlight brightness in different areas to increase contrast. That's why it appeared local dimming technology, which allows you to control groups of several LEDs at once. The local dimming system has several disadvantages. Firstly, poor color uniformity (bright and dark spots are noticeable) in areas where the backlight is brightly turned on and off. Secondly, colored halos appear at contrasting transitions. Thirdly, image details disappear in dark areas. But the increase in contrast and black level compensates for these shortcomings.

If we rank different technologies according to the indicator quality of the resulting picture, then you get the following result:

1. LED lighting using the Direct method;
2. LED lighting using the Edge method;
3. CCFL lamp backlight.

Today's LED TV models have screen resolutions from HD Ready to Full HD, and this year there are also models with 4K Ultra HD resolution. LED models can also have functions such as 3D, Smart TV, a wide variety of connectors and other parameters. So every buyer among the models of LED TVs will be able to choose a suitable purchase for himself.

Lately, many people have been wondering what an LED TV is? These units have proven themselves well and managed to gain wide popularity. The cost of this is gradually decreasing, making them much more affordable. Not everyone understands what an LED TV is, so it’s worth understanding the principle of its operation and discussing the pros and cons associated with production technology.

Essentially, this device is a liquid crystal TV in which the screen is illuminated using LEDs. Earlier models of LCD TVs use cold cathode lamps. It is worth mentioning the advantages of using an LED matrix for backlighting. Manufacturers talk about a significant increase in image quality. There are a number of parameters that have a direct impact on how viewers perceive an image. These include brightness, contrast level, black depth and color rendering quality. In most cases, LED-backlit TVs are significantly ahead of their counterparts.

If we talk about what an LED TV is, then it’s worth saying that the mentioned feature is associated with design features By adjusting the glow level of the diodes, it is quite possible to achieve absolute control over the brightening or darkening of certain areas of the screen. When turned off, the LED does not create any glow, so a group of turned off diodes creates completely black areas. Thanks to the use of this technology, it is possible to achieve deep black color display, as well as excellent contrast levels. Overall color rendition also becomes significantly better, which has a positive effect on image quality. Thanks to the glow of LEDs, LED LCD TVs have high screen brightness. Using a diode matrix allows you to make most of the parameters that are responsible for outputting a high-quality image much better. The significant reduction in energy consumption is another major benefit.

Speaking about what an LED TV is, it is necessary to mention that harmful aerosols and mercury are not used in production, and this has a beneficial effect on B. Both single-color and three-color diodes can be used, which can significantly increase the number of displayed colors. It is common practice to use white LED backlights, which reduces the risk of image problems.

Manufactured using "local dimming" technology, which is responsible for local dimming. According to it, LEDs are controlled in groups consisting of several individual elements. The disadvantage of this technology is the possibility of poor uniformity in the output image. Usually this is the appearance of bright spots in areas where the backlight is brightly turned on and dark spots where the backlight is completely turned off.

Most homes have more than one TV. Maybe two, three or more. They are installed in different rooms - in the kitchen, in the living room, in the bedroom or in the nursery. Depending on the place of “registration”, the requirements and selection criteria change. So it turns out that choosing a TV is not so easy.

To choose a TV, you first need to decide at least on the technology by which it will be manufactured. They all have their pros and cons. But even the disadvantages can be used “for good.”

Plasma screens

The design of a plasma panel is fundamentally different from all other technologies. Between two glass plates there are cells filled with gas - xenon or neon. That’s why such TVs are sometimes called gas-discharge TVs. When current passes, the cells glow, the brightness of the glow depends on the magnitude of the current.

The main advantage of this technology: high quality of the “picture”, which is preserved even in very dynamic moments. Other advantages of this technology are no less impressive:

Very good indicators that contributed to the rapid growth of popularity. But there are also disadvantages:

If you want to choose a TV with big screen, high-quality images and good color rendition, pay attention to plasma panels. This is exactly them. Only if you want, you will have to look for appropriate brackets and the wall must have good load-bearing capacity. Drywall or foam concrete will not hold such a mass.

Properties of LCD TVs (LCD)

Liquid crystal screens use a digital image transmission method. They are so named because the cells are filled with liquid crystals, which in an electromagnetic field polarize the light passing through them, changing the degree of their own transparency. To obtain an image, a matrix with liquid crystals is illuminated from behind (cold cathode lamps), and color filters are used to convey shades.

The advantages of LCD TVs are as follows:

• Recent models have low power consumption.
• More a high resolution(compared to plasma).
• Possibility of playback in FullHD format.
• Light weight.
• There are screens of different sizes - both small and large. The image on them has the same quality.
• Good image geometry.
• Low level electromagnetic radiation since they are powered by reduced voltage.
• There is no screen burn-in or see-through.
• The screen does not attract dust.

A similar set of qualities contributed to the rapid spread of televisions with liquid crystal screens. But they also have a number of disadvantages that are worth knowing about:

If you want to choose an LCD TV with good resolution, you will have to shell out a substantial amount. If the requirements for image quality are not so strict, it is quite possible to look at models from the mid-price range.

LED technology

The difference between LCD and LED TVs is in the various lamps used to backlight the matrix. LED TVs use LEDs. They are smaller in size, which allows for very thin screens. They are also more durable and consume less electricity. There are two types of LED screen backlighting:

Through the use of LEDs, LCD TVs receive additional advantages:

If you decide to choose a TV with high quality images, take a closer look at the LED models. They have, perhaps, only one drawback - the high price. Good quality LED TV costs $600-1000. Compared to conventional LCDs, they cost 40-50% more. However, these are not the most expensive models today and many people opt for LED TVs.

OLED and QLED technology

This technology for making televisions appeared already in this century, and they have been mass-produced for only four years. The image is formed by organic light-emitting diodes, which themselves emit light and do not require backlighting. In English they are designated OLED, which gives this type of TV its name.

Today there are two main technologies for producing OLED TVs:

Quite recently - in the midst of summer, a report was published on our website Samsung LED TVs: from Kaluga with love, dedicated to the opening of the Russian Samsung plant for the production of various electronics and household appliances- Samsung Electronics Rus Kaluga (SERK). Let me remind you: the key point of the report was the story about the launch of production lines for the production of the most modern and most relevant flat panel panels today Samsung TVs with LED backlighting - the so-called LED TV. Since then, the editorial mail has received more than once letters in which our readers ask us to tell them more about LED TV technology. The main questions lie in the technical details of the technology, its advantages over competing proposals, and so on. But almost always we are talking about the price factor: is it really worth paying for an LED TV an amount that is sometimes more than twice the cost of LCD and plasma TVs with similar diagonals and screen resolution, will there be a real return on such costs. What is typical is that as time passes, the relevance of the questions asked does not decrease. Flat panel TVs are becoming fashionable, and their range is constantly expanding. You don’t have to look far for an example: the Kaluga plant of Samsung Electronics plans to produce about 75 thousand televisions of all three LED TV series - 6000, 7000 and 8000, with diagonals of 32, 37, 40, 46 and 55 inches by the end of the year and with special emphasis on the most popular are 32- and 40-inch models. Already now, these models are present on the shelves of most Russian retail chains, along with this, the choice of “LED” TV models from other companies is growing, so the growing interest in this technology is quite understandable. In short, today we publish short review features of the production technology of flat panel displays with LED backlighting.

LED TV or LED LCD TV?

To begin with, it is worth deciding on the terminology that has been established by now. The term LED TV, first coined by Samsung Electronics and used by a number of companies, and different variations This term like LED-backlit LCD, used by other companies, in practice means that we are talking about the good old flat-panel LCD screen, but equipped with a more modern and high-quality LED backlight. In other words, to say that LED TV is exactly LED TV from a technical point of view it would not be entirely correct. Various technologies where light-emitting diodes form the “picture” - such as OLED, OEL or AMOLED, belong to a slightly different class of displays. Real LED screen– where each pixel is displayed using one LED or a group of LEDs, can be found, for example, on huge billboards, looking at which from afar we see a whole picture, and not individual LEDs. Another example is Organic Light-Emitting Diode (OLED) displays, where certain types of organic polymer materials emit light when exposed electric current. OLED technology is truly promising as the basis for the production of high-quality displays for televisions and monitors - such displays are lighter, do not require backlighting, have better color rendition, a larger brightness range, lower power consumption, and in some versions even flexibility. Moreover, as technology improves, it is expected that over time the production of OLED displays will become even more profitable than the production of LCD screens. However, due to a number of technological limitations - for example, the lifespan of blue polymer phosphors, which is noticeably shorter than that of red and green organic LEDs, OLED technology is currently used mainly in the production of small diagonal screens for various mobile devices. Serially produced OLED TVs currently have a small diagonal; rather, they are rare exotics with a huge price rather than a mass product. Although, I repeat, the prospects for the technology are promising. So, let’s dwell on what the use of the term LED TV in practice means: we are talking about an LCD TV equipped with modern LED backlighting. In other words, it would be appropriate to label such TVs as LED LCD TV. However, Samsung has adopted a shorter and, apparently, more convenient marketing option - LED TV. Or LED-backlit LCD in other versions.

LED TV vs CCFL LCD TV

Everything is relative. Until recently, we used LCD TVs and monitors, most of them equipped with traditional backlighting based on so-called cold cathode fluorescent lamps (CCFL), in other words, lamps daylight. The production of screens using CCFL LCD technology has been “tested” on many generations of such devices and is currently relatively inexpensive, and convenient compared to previous generation displays on cathode ray tubes, mainly such as lower weight and lower power consumption, have led to the widespread (although not complete) displacement of the latter from everyday use. And everything would be fine, but illumination using fluorescent lamps has a number of disadvantages that can be considered fundamental. For example, with CCFL backlighting it is quite difficult to realize really deep black tones - constantly switched on lamps still create a certain “leakage” of light even in those parts of the image that are intended to be this moment must be dark. This also logically implies a subjectively perceived decrease in picture clarity. In addition, fluorescent lighting makes it difficult to reproduce multiple colors, making it very difficult to achieve good color saturation. Among other problems of CCFL LCD technology, one cannot fail to note the difficulty in achieving high frequencies scans, limited lamp life, relatively high energy consumption, and, finally, an environmental nuance - the need to use mercury in lamps. In a word, one way or another, the need to replace fluorescent lamps with something more efficient has matured a long time ago, and as a result of numerous experiments, the choice fell on LED backlighting. With its help, you can improve at least four key factors of image quality: brightness, contrast, image clarity and color gamut. Not to mention the more uniform nature of such illumination, which is important when viewing dimly lit scenes with initially low contrast. In addition to this, it is also worth mentioning that the efficiency of LEDs and longer operating time without loss of performance can significantly reduce the power consumption of LED TV compared to conventional LCD TVs with CCFL LCD technology.

LED backlighting varies

To date, a number of different technologies for backlighting LCD screens using LEDs have been developed. As a rule, to create backlight modules (Back Light Unit, BLU), LED arrays composed of white or multi-colored RGB (Red, Green, Blue) LEDs are used. The backlight principle is also represented by two main options: direct (Direct) and edge (Edge). In the first case, it is an array of LEDs located behind the LCD panel. Another method that allows you to create ultra-thin displays is called Edge-LED and involves placing backlight LEDs around the perimeter of the inner frame of the panel, and uniform distribution of the backlight is carried out using a special diffuser panel located behind the LCD screen - as is done in mobile devices. Proponents of direct LED backlighting promise better results due to more LEDs and local dimming technology to reduce color casting. The reverse side of direct illumination - large quantity LEDs and the accompanying increase in energy consumption and price. In addition, you will have to forget about the ultra-thin design of the TV. Proponents of edge lighting, in addition to saving energy, promise no worse quality with a thinner design. Today, many global companies are producing LCD TVs with LED backlighting, including Samsung Electronics, Toshiba, Philips, LG Electronics, Sony and others. Each company uses variations of the above technologies in its LCD TVs and LED-backlit monitors. So, for example, in Sony TVs Edge LED technology is used, which has made it possible to significantly reduce the thickness of fairly large TVs.

However, further we will look at LED TV technology using the example of Samsung Electronics TVs - for the reason that currently in Russia Samsung’s share of the LED TV market reaches 98%.

Samsung LED backlighting: how it works

At its core, an LCD screen is a multilayer “pie” made up of color filters, liquid crystal arrays, backlight lamps, etc. The liquid crystal cells themselves do not glow, but, depending on the voltage level applied to them, they open to allow light to pass through fully, partially open, or simply closed when a dark area of ​​the picture is displayed.

The role of the backlight lamps in this whole story is to illuminate the slightly opened LCD cells so that the final picture appears on the screen. Despite such a simplified retelling of the operating principle of the LCD display, this is quite enough to understand the purpose of its main components. The thickness of the layers of the “pie” of different LCD screens is different. When using traditional fluorescent lamps, the backlight layer is so thick that it occupies more volume than all other layers combined.

Let's replace the fluorescent lamps backlighting the LCD cells with LEDs. The first obvious effect of such a replacement is a significant reduction in the overall thickness of the LCD panel. Moreover, in Samsung LED TVs, the LEDs are placed not behind the matrix, but along its edges, due to which the presence of such an end layer has practically no effect on the overall thickness, but the overall weight is significantly reduced.

The LED BLU light-directing layer ensures uniform illumination in all areas of the screen. Thanks to a special reflective grille, the light transmission efficiency of Samsung LED TVs is stated to be 20% higher than that of models with direct RGB LED backlighting. In addition, instead of the usual 10 or more centimeters in thickness, it turns out to be less than 3 cm - if you want, put such a TV on a shelf, or if you want, hang it like a picture on the wall using a specially designed lightweight mounting system. The thickness of Samsung LED TVs 8000 series in the thinnest part of the body is 11 mm, in the thickest part – 29.9 mm. In advertising, Samsung always indicates the value obtained by measuring the thickest part of the case.

For reference: Samsung 8000 series LED TVs use 324 LEDs for backlighting. Thanks to the complete abandonment fluorescent lamps LED TVs do not contain a single gram of mercury. IN Samsung technology In addition to this, it was also possible to completely get rid of soldering using lead compounds, and to practically reduce emissions of volatile organics and other harmful by-products by eliminating the use of sprayed powder paints - the thin, durable and attractive body of the new TVs is made using a special Crystal Design casting technology. Another significant advantage of LED TVs is the high level of image contrast, which significantly exceeds the best performance of traditional LCD matrices. The brightness of LEDs is so high that, for example, in LED TVs Samsung series 6000, 7000 and 8000 the contrast ratio reaches 1,000,000:1. In addition digital processing signal with Mega Dynamic Contrast technology provides a detailed image in low-contrast “twilight” areas of the picture.

Maximum possibilities new system The backlight is squeezed out using a multi-layer Ultra Clear Panel filter, which transmits light from inside the screen and does not reflect it from the outside, so it is possible to achieve better brightness and contrast with a minimum of glare, regardless of how the screen is illuminated from the outside - sunlight or artificial electric lighting. LED backlight allows you to achieve white illumination of LCD cells, as a result of which it is possible to display a wider and more natural range of color shades. The color palette of LED TVs is richer and richer; the greens and blues of bright areas no longer look faded and pale compared to conventional models. In Samsung LED TVs, color saturation is also additionally monitored by the Wide Color Enhancer Pro hardware technology. Often, the weak point of LCD screens is the blurred image with a long response time, which reduces the sharpness of the image and reduces the smooth movement of objects in dynamic scenes. In the new Samsung LED TVs, this is monitored by the Motion Plus interpolation system: models of the 6000 and 7000 series have double the 100-Hz scan, and the flagship 8000 series have quadruple the 200 Hz scan.

An important factor is electricity consumption. Traditional LCD TVs are, of course, more economical old models with cathode-ray picture tubes, but do not forget that the diagonals are no longer the same, so with large LCD TVs, electricity meters still spin quite quickly. As for the new LED models, LED backlighting can significantly reduce energy consumption without sacrificing image brightness.

In addition to significant energy savings - up to 40% compared to traditional LCD models with the same diagonal, Samsung LED TVs can also boast certification to one of the most stringent environmental standards, Energy Star 3.0.

LED TV Samsung: it's not just a TV...

Everything on a TV should be perfect - both characteristics and appearance, and a set of functions. Since we are talking today about specific Samsung LED TVs produced today in Kaluga, it would be an omission not to mention their main characteristics. This is only indirectly related to the topic of today’s article; however, I believe a few lines of details about the potential item of purchase will not be superfluous.

First of all, Samsung LED TVs of the 6000, 7000 and 8000 series, along with the reception of traditional analog channels ready to work with digital TV thanks to the presence of built-in DVB-T/C tuners. Whenever the era of ubiquity arrives digital television in Russia, you are already ready for this. In addition, the LNA plus tuner used in these models was created specifically taking into account Russian specifics - interference, vast open spaces and not the first freshness of television repeaters. In addition to this, thanks to the presence of two ports USB new TVs can be used as a photo frame for viewing photos from a flash drive, watching multimedia videos in DivX/Xvid formats, for example, from an external USB hard drive, but it won’t be enough - there is a built-in 2 GB of flash memory with pre-loaded content. The TV can be "registered" in home network with access to laptops, desktops and external data storage, and the TV remote control turns into a wireless keyboard for navigating through folders and displaying content from different places networks. For Internet access there is a LAN connector and support for Internet@TV with access to YouTube. The sound system in ultra-thin LED TVs is at the same level best models Samsung. A unique flat subwoofer was created especially for ultra-thin LED TVs, plus well-proven hidden speakers are used.

Finally, communication with consumer electronics (DVD player, Blu-ray player, AV receiver, cinema, HD video camera, game console) can be carried out using an HDMI connection, of which in the LED design Samsung models Four pieces are provided.

LED TV: are there any disadvantages?

Yes, but what about: this is the price. So far, LED TVs are much more expensive than their traditionally backlit counterparts. However, the way out of such a price situation will be traditional: lower prices as demand grows and mass production increases. So far, the size of the LED TV market is small, but the interest in such models due to their outstanding characteristics is enormous all over the world. According to Display Search analysts, next year every fifth TV sold will be made using LED TV technology, and in a couple of years – every second. By this time, we can expect prices to decline.

What is LED TV?

Every year more and more new terms appear, it is impossible to keep up with it all and know everything. Technology is developing at a rapid pace these days. And the Internet will always come to our aid and tell us about any innovations. Buyers now face a particularly difficult task when choosing a TV.

What is LED TV

It would be logical to start by deciphering the abbreviation LED, which in English sounds like this: light-emitting diode. And the translation into Russian is much simpler - “LED”. But you cannot call an LED TV an LED TV. What could all this mean?

Roughly speaking, an LED TV is an LCD TV. To understand the difference between one and the other, let’s look at the features of LCD TVs. Their main part is a matrix with pixels (luminous dots). By the way, the number of these same pixels determines the screen resolution (for example, 640x480 = 307,200 pixels). So, in LCD TVs, the matrix is ​​illuminated by cold cathode fluorescent lamps. LED TVs use LEDs as light sources. This is considered a big plus modern technology, because the use of LEDs makes it possible to produce LED TVs that are very thin. Their thickness is approximately 2.5 cm. LED TVs will practically fit into any interior. Thus, we get lower power consumption (40% lower compared to LCD TVs of the same size), longer service life and best level contrast ratio, which is not so far from the well-known competitor of LCD TVs - plasma panels. Just imagine what a natural and deep black color it will be led tv ah, if their contrast level reaches 1,000,000:1.

Now remember the big disadvantage of LCD TVs - distortion when moving objects are displayed... There will be no such drawback in LED TVs, thanks to a frame refresh rate of up to 200 Hz. You probably immediately understood what an LED TV is and imagined the perfect video game or long-awaited sports match. Undoubtedly, this technology The use of LED backlighting will sooner or later become a standard and displace traditional technology from the market. LED TVs should not be perceived as a new type, it is simply a technical development of LCD TVs.

To understand what an LED TV is, let’s take a closer look at its LED backlighting. There are two types:

1. White LED - LED elements are located around the perimeter of the matrix, that is, the light is distributed evenly, thanks to a special light-conducting panel.

RGB LED - LED elements are located throughout the backlighting area, and the light elements have different colors, that is, different areas of the screen are illuminated in different colors, and this improves the quality of color rendering. Of course, this type of LED backlight will be more expensive, but its advantages can be found everywhere. Because of this high cost, many companies, for example, Samsung, have to abandon this RGB LED and continue to work with side lighting.

Judging the benefits of backlights became more difficult when, in 2009, Toshiba announced that the “white” backlight was even more effective than a second RGB LED.

We would like to draw your attention to one more advantage of LED TVs. They can be considered more environmentally friendly than conventional LCDs. CCFL lamps (which are used for backlighting in LCD TVs) contain mercury, but LEDs do not. Not that this is a breakthrough in technology, but a big step forward. Experts recommend choosing LED TVs, despite the fact that they are twice as expensive as LCD TVs. But you now know what an LED TV is, and you understand that it will gradually become a standard in TV production.