What is LED TV? LED TV technology - how it works

In this article we will look at what LED technology is and where it is used. I’ll say right away that not only the matrices of monitors and televisions (), but also anything from the bottom of a car to tap water are illuminated. Now let's talk about this in more detail.

Generally speaking, an LCD monitor is a device that consists of just a few basic components. This is a pixel matrix, backlight and top protective layer. In this case, the image itself is generated by a matrix of pixels, but since it does not emit light at all, it has to be illuminated from behind. You can shine a flashlight from the front, but it’s unlikely that anyone will sit and shine it into the monitor while working;) A backlight is used for this.

Previously, in older models of LCD monitors, it was electroluminescent, that is, a tube with gas, as in lamps for lighting schools, offices, and so on. It is clear that in monitors and televisions such lamps are much smaller, and the gas is different, but the main operating principle is the same. Now, in most new models, it is used LED backlight, that is, LED (light emitting diodes).

When using lamps, they are installed around the perimeter of the screen, and to distribute the light evenly from the perimeter to the center, reflectors and light-diffusing filters are used.

When using LED backlighting, two options are possible. The first is traditional, cheap and practical - the same installation around the perimeter. In this case, everything is done in the same way as with lamps - diodes are installed around the perimeter and their light is carried to the center by reflectors and various filters. But, naturally, there will be no improvement in the quality (uniformity) of illumination compared to electroluminescent lamps. But, however, there are advantages! Reducing energy consumption when using LED backlighting is reduced several times. As, in fact, the release of heat.

All of the above applies to the budget - white backlight (although it is actually blue, additional yellow filters are simply used). It is installed on the sides for the same purpose - saving money. Such monitors sell out faster because they do not scare away consumers with their prices. But there is another option for installing the backlight - over the entire surface of the matrix. It is much more uniform and of better quality, and besides, it is also colored. Yes, this is the so-called RGB LED backlight. It consists of RGB LEDs in three colors: red, green and blue. Located over the entire area of the matrix, such a backlight can be turned off to obtain an absolutely black color on the screen, or can be illuminated with a certain color, giving the picture brightness and color saturation.

However, since the cells can be quite large, if part of the backlight is completely turned off to obtain black, part of the image that should be bright may also be affected. But, most likely, this will all be solved simply by increasing the number of LED cells or even controlling individual diodes yourself, it will just require more computing power central processor at the monitor.

LED lighting throughout

In fact, backlighting can be used anywhere. For example, I have selected for you some successful, in my opinion, pictures with diodes.

LED bike lighting

Sofa with lighting

As you can see, everything depends only on imagination. LED lighting is perfect for cars, bicycles, furniture and even showers or faucets. Quite interesting effects are obtained and your hands begin to itch to do something similar, well, go ahead! Don't hold back :)

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 an 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 are publishing a brief overview of the 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 introduced by Samsung Electronics and used by a number of companies, and various variations of 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 backlight – LED. 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. A 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 to 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, currently OLED technology mainly used 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, in everyday life, Samsung has nevertheless adopted a shorter and, apparently, more convenient option in marketing terms - LED TV. Or LED-backlit LCD in other versions.

LED TV vs CCFL LCD TV

Everything is learned by comparison. 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, fluorescent lamps. The production of screens using CCFL LCD technology has been “tested” on many generations of such devices and is now relatively inexpensive, and the advantages compared to the previous generation of cathode ray tube displays, mainly such as lower weight and lower power consumption, have led to widespread (although and not final) displacement of the latter from everyday life. 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, according to the idea, should be dark at the moment. 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. It can improve at least four key factors of image quality: brightness, contrast, image clarity and color scheme. 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 TVs 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. Reverse side direct illumination – more 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. For example, Sony TVs use Edge technology LED, which 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 8000 series LED TVs is 11 mm in the thinnest part of the body, and 29.9 mm in the thickest part. 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 elimination of fluorescent lamps, LED TVs do not contain a single gram of mercury. In addition to this, Samsung technology has also managed to completely get rid of soldering using lead compounds, and practically reduce emissions of volatile organics and other harmful by-products to zero by eliminating the use of sprayed powder paints - the thin, durable and attractive body of the new TVs is made using a special casting technology Crystal Design. Another significant advantage of LED TVs is high level image contrast, significantly exceeding 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 smoothness of the 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 than previous models with cathode ray picture tubes, but don’t 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 according to one of the most stringent environmental standards. Energy standards Star 3.0.

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

Everything on a TV should be perfect - characteristics, appearance, and 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, connection with consumer electronics DVD player, Blu-ray player, AV receiver, cinema, HD video camera, game console, can be done using a connection via HDMI interface, of which four are provided in the design of Samsung LED models.

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.

TV models with LED backlighting dominate the market and deservedly so. In this article we will look at the types of LED backlights on modern TVs and evaluate their effectiveness.

LED TVs

Let's start with the fact that LED TV is not a new type of HDTV. . Unlike plasma and OLED TVs, which are made on the basis of emitting technologies, where each pixel is a separate light source, in liquid crystal models, each pixel of the LCD matrix requires lighting (from behind or from the side through a lens system). So LED HDTV models are the same liquid crystal (LCD or LCD) TVs, but they have a built-in light-emitting diode (LED) backlight, which replaces the standard cold cathode fluorescent lamp (abbreviated CCFL).

2 types of LED backlight according to design: matrix and side

LED backlighting with local dimming. First, televisions with LED backlight, used to illuminate the cells of the LCD matrix " full array"(full array) of LEDs, similar to standard TVs based on backlight using CCFL lamps. But to change the thickness of TVs downward, the developers abandoned the use of a full array LED LEDs behind the screen, installing the light source lines on the side of the LCD panel. Thus, the distribution of light from LED sources over the entire screen area is carried out using LEDs special form. Model data LCD TV ov is called TV with side or regional LED backlight, which still dominate today.

LED lighting with local dimming system allows you to automatically reduce the brightness or completely turn off individual groups of backlight sources. Most modern LCD TVs with LED backlighting are equipped with a full array of LED sources placed behind the LCD panel. dynamic backlight technology also called local or local dimming. Using local dimming, specific areas of the overall backlight LED array become darker or lighter depending on the brightness and color of the corresponding part of the image on the screen.

The ability to darken a specific area of the screen can reduce the amount of light that passes through the closed pixels of the LCD panel, which has a positive effect on the rendering of blacks, which become darker and more realistic. Because black levels are critical to contrast, the perception of depth on black surfaces, full-color images become more vibrant and clear. Local dimming technology has the only drawback - the effect of local dimming, which is formed when part of the light from brighter zones leaks into neighboring darker ones, which subsequently brightens at the border dark color. It is quite difficult to notice the clouding effect on most models, since the disadvantage is directly related to the number of local dimming zones behind the screen, and manufacturers do not always provide such information.

When using standard backlighting using CCFL lamps and in most LCD TVs with edge LED backlighting, all backlight sources brighten or dim simultaneously (the so-called " global dimming"), but among Samsung and LG TV models there are rarely displays with side LED backlighting, which can also work on the principle of local dimming (“precision dimming” for Samsung and “LED Plus” for LG). To put it simply, this is a local dimming sham.

Thin models with side LED backlight Of course, they suffer from uneven screen illumination, but not everyone. Main feature of TVs with side LED backlighting– thin body, therefore it is difficult to ensure uniform distribution luminous flux across the entire screen plane. When purchasing a TV, play an image of the white surface on the edge-lit LED display screen to check that there are no brighter areas around the edges of the screen. Likewise, when the screen is filled with a black field, the edges should not appear lighter (gray).

It is also worth noting that LED backlighting, regardless of the type, does not improve the viewing angles of the LCD panel. Black level in use LED backlight and a possible shift in the angle of view by 1-2 meters to the left or right falls.

We must not forget about the energy efficiency of LED backlighting. Of course, the consumption of any model is significantly affected by the size of the screen and the brightness of the backlight sources. LCD TV models of both types of LED backlighting are much more energy efficient compared to plasma models.

LED backlights for LCD displays are divided into categories according to the following criteria:

glow color: white or RGB;
lighting uniformity: static or dynamic;
design: matrix or side (this is described in more detail above)

RGB backlighting is used to fine-tune the light spectrum. In addition, additional compensation for changes in the emission spectrum of LEDs over time is often used. LED TVs with RGB LED backlighting light up different areas of the screen depending on the color of the image. Colored backlighting provides enhanced contrast and deep blacks, as demonstrated by many Sony LED TVs.

Edge LED: Better Color Rendering

Sony in its new flagship TV models - for example, the W905 line - uses Triluminos technology. The LED backlight (Edge LED) built into the frame of the TV on all sides of the screen is complemented by so-called quantum dots - fragments of a semiconductor several hundred atoms in size that emit light in a strictly specified range. Triluminos technology is designed to minimize color distortion and provide enhanced red and green tones. This will allow you to achieve an extremely uniform and natural image with a significantly wider color gamut. Tests of the first devices with Triluminos support did not disappoint us: the color gamut of the Sony KDL-46W905A model is comparable to that of organic light-emitting diode (OLED) solutions and is unattainable for LED-backlit LCD TVs. The W805 and W605 series devices, which also went on sale this year, do not use Triluminos, making their cost significantly lower. In the future, manufacturers will be able to completely abandon LED backlighting in favor of quantum dots.

OLED TVs: brightness and color at their best

TVs with OLED screens have already reached stores, and developers have rushed to release new models with concave displays. Last year, LG planned to introduce a 55-inch OLED TV to the market, but it only went on sale this summer. In Russia, the 55EM9600 model and its improved analogue 55EM9700 will cost the buyer 500,000 rubles. In addition, the device is sold in Europe, the USA and some other countries.

Advantages of OLED TVs: it is not a type of backlight, but a different technology

accurate color reproduction
greater brightness margin compared to other technologies
high contrast compared to LCD models (another imaging technology).
absence of an LCD matrix and LED backlight - their place was taken by a matrix made of light-emitting organic diodes.

Samsung and LG independently developed OLED TVs with concave screens (Curved OLED). This design is designed to minimize distortion at the edges of the image and increase detail. New items are still available in limited quantities in South Korea, USA and some European countries. 55-inch Samsung model KN55S9C is priced by the manufacturer at $9,000 (300,000 rubles).

Of particular interest is also Multi-View technology, implemented in many models of OLED TVs, both flat and concave screens. Due to the extremely short response time similar devices allow you to simultaneously demonstrate two or four programs in high definition format (Full HD) or two different films in 3D format. Shutter glasses are used to separate the image. Each viewer can use the controls located on the glasses to select an individual program for viewing. At the same time, thanks to the built-in headphones, playback of the soundtrack corresponding to the film is ensured.

Choosing suitable model TV, many consumers are faced with new terms and modern technologies. For example, not everyone knows what a TV with LED technology is and what principle its operation is based on. Despite this, today this type of flat devices is most popular among buyers, so they are considered a completely common attribute in the home. Before you do it, you should still figure out what the abbreviation LED means, how such TVs differ, and what advantages they have over other types of TV.

If translated literally, then LED – light emitting diode. However, it is advisable to believe that it cannot serve as a complete definition. In fact, modern led tv is a representative of long-known liquid crystal panels. The main component is an LCD matrix with many luminous dots - pixels. But if the usual LCD devices used fluorescent lamps as backlight, then the devices in question use LEDs, that is, TVs with such backlighting are more advanced options LCD-models.

Samsung developers were the first to use this technology. As a marketing ploy, the new TVs were given the name LED TV, which is still used today.

LEDs here act as light sources, and are not the actual unit of the image being formed. Therefore, it would be more correct to call such panels LCD TV with modern LED backlighting.

Types of LED backlight

In order to understand what the fundamental feature of such equipment is, you need to understand the types of TV backlighting. Today, several systems are used; they differ in color and arrangement.

By color of light sources

White led or single color system(white LEDs). It is considered a budget solution, but still outperforms fluorescent lamps. LEDs are more energy efficient and do not contain mercury. As for color rendering and coverage depth, LED TVs with this type of backlight are not much different from LCDs; the difference is more significant in the next option.
RGB or multi-color system. Their color palette is much wider. Due to this, color rendition improves. But it is worth noting that models with a similar backlight option are more expensive, which is not commensurate with the achieved effect. Such models require a powerful graphics processor, and they consume more electricity. Since such HDTVs are not affordable for every group of consumers, leading companies decide to abandon RGB backlighting and continue to search for analog technology.
QD Vision or mixed backlight option. Based on LEDs purely blue and a special film with quantum dots that have green and red colors. This technology makes it possible to emit a strictly limited and tuned spectrum of optical waves. Due to this, the color palette and intensity of colors expands, at the same time, technology, unlike RGB LEDs more energy efficient. A striking example of a mixed backlight option is the line of Bravia television panels, the leading manufacturer of Triluminos Sony.

In fact, the question of using the first and second backlight options continues to find many controversial opinions. For example, the famous digital technology developer Toshiba claims that white TV backlighting is much more effective than RGB. So why spend a ton of money when you can save millions?

According to the lighting placement option

There are 2 options here.

Along the perimeter of the LCD matrix(Edge LED). This is a one-color system (White led), which can be located on one side (most often from the bottom), on parallel sides (on the sides) or along the entire perimeter. The method of organizing side lighting depends on the size of the screen diagonal. The disadvantages of such backlighting include “flares” at the edges of the TV screen and an insufficient level of contrast (compared to the second type). But this technology makes it possible to create panels only a few millimeters thick.
Directly behind the LCD matrix (Direct LED). It is based on the uniform distribution of diodes over the entire area. In terms of price, it is more expensive than edge lighting. The main advantage of such a system is the ability to use local black dimming technology. Both white and color LEDs can be used here; they significantly improve image quality.

If you already own such a TV and have problems with the image, you may find information about

Advantages of LED TVs

These panels have significant advantages, which is why they are popular among consumers. Of the main advantages, the following factors should be noted.

Case thickness. It is through the use of LEDs that the production of ultra-thin models has become possible. This TV can be easily mounted on the wall using a bracket;
Contrast and image clarity. LED TV is the main competitor to other types of TVs because it has excellent quality image reproduction, adjusting the contrast level. Remembering when problems with the perception of moving objects were observed, it can be noted that with modern ice screens such problems will not arise.
Energy efficiency. Energy savings are perhaps the main point that attracts many buyers. Compared to its predecessors, the LED device consumes 40% less resources.
Wide range of models not only in functionality, but also in appearance. Such a panel will decorate absolutely any interior without any problems. Leading manufacturers have a huge number of models, including both classic solutions and interesting shapes and colors.
Durability. Thanks to the use of fade-resistant LEDs, TVs have a longer service life.

But the improvement of such television panels does not end there. Already appearing on store shelves todayOLEDTV, the illumination of which is based on organic light-emitting diodes. They have an even thinner body, low weight (relative to their diagonal), wide angle visibility, absence of “lights” and glare, excellent color rendition. However, this does not mean that other lower class models will lose demand. Innovative technologies of this format are not cheap, and the financial capabilities of most consumers will not allow having such a widescreen panel at home. Therefore, the demand for simple models of modern LED TVs is unlikely to fall in the near future. Detailed comparative characteristics both types are given in the article

Every person, when choosing a TV for themselves, learns about the latest achievements of science, gets acquainted with new technologies and terms. One of modern technologies in the field of television is LED. In reality, an LED TV is an ordinary liquid crystal LCD TV. This means that the image in it is formed using a matrix consisting of pixels.

Features of the technology

If in older devices the backlight was a fluorescent lamp, then in LED models the backlight is a matrix consisting of a set of LEDs (Light Emitting Diode).

Light Emitting Diode is translated as “light emitting diode”. The scope of their application is extensive: these are car headlights, traffic lights, lamps, spotlights, street and home lamps. In a TV, light from LEDs is directed onto the LCD screen, illuminating the image.

Of course, it would be more logical to call these models LCD TVs with LED backlighting. However, Samsung, which is a pioneer in this field, called these models "LED TV". The term became popular and began to denote a class of new televisions. The LEDs in these TV receivers do not form a picture as a real unit (pixel). Therefore, LED TVs cannot be considered full-fledged LED models.

How LED lighting works

To understand the operating principles and features of this device, you need to become familiar with the types of backlighting on a TV. Currently, several lighting systems have been developed. They differ from each other in their location and color.

Color of glow sources

Single color system (White led) more energy efficient than fluorescent lamps, but is still considered a budget option. LEDs do not contain mercury, like lamps, but in terms of color rendering and coverage depth, LED TVs with this backlight are practically no different from LCDs.

Multi-color system (RGB) compares favorably with the previous version. TVs with this backlight have a wide color palette. Accordingly, very good color rendition. Unfortunately, this effect comes at a higher price. To operate such models, you need a modern, powerful GPU. These TVs consume more electricity and have a more bulky body, comparatively speaking, of course. The cost of these TVs limits demand, so leading companies are gradually abandoning RGB backlighting and are looking towards analog household appliances.

Mixed backlight option (QD VIsion) uses only blue LEDs and special films. The film is a collection of quantum dots that have red and green colors. This allows you to have a tuned spectrum of optical waves, limited in range. Due to this, the color palette expands, and the brightness and intensity improves. Unlike the RGB system, this technology is more energy efficient.

The answer to the question of which backlight option to use is ambiguous. There are still various controversial opinions and discussions on this matter. Toshiba believes that white backlighting, based on all its characteristics, is preferable to RGB.

Accommodation options

There are two options for placing the backlight:

General advantages of LED TVs

These devices are an undoubted step forward in the development of television. They enjoy deserved popularity in everyday life. There are several main advantages:

Manufacturers are constantly working to improve these panels. The new technology is called OLED TV. In these TVs, the backlight is organized using organic light-emitting diodes. They are characterized by an even thinner body and improved color rendering.

Speaking about LED technologies, we should not forget that in the manufacture of LED TVs they do not use, as before, harmful substances - mercury and aerosols.

Some LED-TV models use “local dimming” technology. It is designed for local dimming. The basic idea is to control groups of LEDs. Each group contains several elements. True, with such an approach separate areas bright spots sometimes appear on the screen in areas where the backlight is turned on full power. And where the backlight is not used, dark spots may appear.

Screen resolution. Determined by the number of pixels that form the image in width and height. The larger this parameter, the more clear image and more different details can be seen on the screen.

LED-TVs mainly have Full HD (1980×1920 pixels) and H.D. Ready (1366×768 pixels) resolution. These are the most popular video formats in present moment. Some premium models have 4K UHD resolution (3840x2160 pixels).

Almost all 4K UHD TVs support HDR. This is an extended dynamic range format that allows you to depict a picture as close to reality as possible.

Screen coating. There are matte and glossy. At matte finish the image is softer. The viewing angle is limited. There is no glare when exposed to sunlight. If the coating is glossy, then the picture on the screen is very bright and contrasting. Visibility becomes poorer in bright sunlight.

Functional connectors. Usually there are standard ones: HDMI output, Ethernet output and USB connector for watching video from a flash drive or hard drive. IN latest models there is a D-sub video port. It involves connecting a computer to a TV.

Sweep frequency. An indicator of how many frames of a film are shown per second. It is measured in Hertz and can reach values up to 960 Hz. For 3D TVs, the frequency can be even higher. The recommended range of values so that the image does not blur and pictures do not overlap one another is 100−200 Hz.

Additional features

DVB-T. Digital television standard. Allows, in addition to analog cable and terrestrial television, connect satellite.

Volumetric 3D image. Using this option, you can view 3D images with active or passive 3D. It is necessary to take care of special glasses.

Smart TV. Allows you to connect and use the Internet. Connection occurs via WiFi module. Connection via network cable is possible. Some TVs allow you to build in an additional router. With Smart T.V. you can play videos from the Internet, play, listen to music, and search for information.

LED devices have become popular. After all, LED TV - what does it mean? This is high quality, convenient and comfortable to use. The advantage of an LCD TV is LED backlighting; all LED models have it. But sometimes you have to pay extra for design features and additional features. What should you pay attention to when choosing an LED TV model?

First of all, you need to decide which diagonal is best to choose. The stores offer a huge selection different models from 19 to 58 inches. Sometimes it’s not very common to calculate in inches and you have to select the size in centimeters, that is, from 48 to 147 cm. The right choice diagonal depends on the size of the room where the TV will be installed.

There is an approximate table of the ratio of diagonal and distance to comfortable viewing.

These data are approximate and allow adjustments within half a meter.

14−17 inches - from 1.5 to 2 m.
21−25 inches - from 2 to 3 m.
26−32 inches - from 3 to 4 m.
34−37 inches - from 4 to 5 m.
42−55 inches - from 5 to 7 m.
61−80 inches - from 7 to 10 m.

So, when choosing a TV, you need to think about its location in the room in advance and select optimal model, based on the layout.

After choosing the TV diagonal, you need to consider the resolution. Here the criterion is the larger the better. Full HD will provide complete comfort and satisfaction from your TV.

The quality of the picture is assessed subjectively. If possible, colors should be natural, without overexposed areas or spots. The image during fast movement should not be jerky, but smooth. The black color must be free of impurities, as black as possible. You should check the transmission of halftones to see if the details are different. The color of the human body: hands, face should be pleasant, without yellow or red spots.

Manufacturers need to be well-known. In addition to the guarantee, this also includes service, as well as the availability of various additional parts and accessories in stores and service centers.

And of course you need to think about additional functions. Do you need Internet access or how important is it to connect your laptop to a large screen?

What is the difference between an LCD and an LED TV?

LED technologies are gradually replacing liquid crystal technologies, since the former are more efficient and economical. This is a serious energy saving and best picture on the screen. Although the differences between these LCD and LED approaches lie only in the way the screen itself is illuminated.

Everything is moving forward. Modern films are produced using the latest technology. Therefore, in order to fully immerse yourself in the atmosphere of the new film, it is better to watch it on LED-TV.

Today, devices with LED backlighting are the best solution in terms of image quality and equipment cost. Modern solutions in TVs of this type make it possible to compete with expensive plasmas (PDP), confidently displacing the latter from the market.

True OLED TVs are very promising. In these panels, LEDs are truly the imaging unit. But these models are still expensive and pay for themselves only with very large sizes screen.

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