TV manufacturers regularly acquaint users with new technologies that improve picture quality. Approaches to combining TV screens and LED elements have long been mastered by the largest companies. Recently, the source of a bright and soft glow is also moving to the displays of mobile devices. Users of traditional lighting based on LEDs can also appreciate the advantages of such a solution, but, of course, the backlighting of LED screens in TVs looks the most attractive. Moreover, it is complemented by other high-tech inclusions used by the developers of this technique.
Illumination device
In the creation of modules for the implementation of illumination, LED-arrays are used, which can consist of white elements of the LED glow or multi-colored, such as RGB. The design of the board for equipping the matrix is specially designed to integrate a specific media model into the device. As a rule, on the left side of the board there are contact connectors, one of which provides power to the LED backlight, while the others are designed to control its operating settings. Also, a special driver is used for LED modules, the function of which is associated withcontroller.
When finished, the LED strip is a row of miniature lamps that are connected in groups of 3. Of course, manufacturers do not recommend interfering with the device of such tapes, but if desired, you can physically shorten or, on the contrary, make the device longer. The standard LED screen backlighting is also dimmable, supports soft start and is supplied with voltage protection.
Classification of backlight by installation type
There are two ways to integrate LED lighting - straight and edge. The first configuration assumes that the array will be located behind the liquid crystal panel. The second option allows you to create very thin screen panels and is called Edge-LED. In this case, the tapes are placed around the perimeter of the inner side of the display. In this case, the uniform distribution of LEDs is carried out using a separate panel, which is located behind the liquid crystal display - usually this type of LED screen backlighting is used in the development of mobile devices. Adherents of direct backlight point to the quality of the result of the glow, which is achieved due to more LEDs, as well as local dimming to reduce color streaks.
Using LED backlight
The average consumer can find this technology on Sony, LG and Samsung TVs, as well as Kodak and Nokia products. Of course,LEDs have become more widespread, but it is in the models of these manufacturers that qualitative changes are observed towards improving the consumer qualities of this solution. One of the main tasks facing the designers was to maintain the screen performance with optimal performance in direct sunlight. Also, LED backlighting has recently improved in terms of increased contrast. If we talk about advances in the direction of the screen design, then there are noticeable reductions in the thickness of the panels, as well as compatibility with a large diagonal. But unresolved issues remain. LEDs are not able to fully reveal their capabilities in the process of displaying information. However, this did not prevent LED technology from replacing CCFL lamps and successfully competing with the new generation of plasma screens.
Stereoscopic effects
Modules based on LEDs have a lot of ability to provide various effects. At this stage of technology development, manufacturers are actively using two stereoscopic solutions. The first one provides for the angular deviation of radiation fluxes with the support of the diffraction effect. The user can perceive this effect while viewing with or without glasses, that is, in the holographic mode. The second effect provides for a shift in the light flux, which is emitted by the backlight of the LED screen in the direction of a given trajectory in the liquid crystal layers. This technology can be used in combination with 2D and3D formats after appropriate conversion or re-encoding. However, with regard to the possibilities of combination with three-dimensional images, LED backlights are not going well.
Compatible with 3D technology
This is not to say that LED-backlit screens have serious interaction problems with 3D format, but special glasses are required for the optimal perception of such a “picture” by the viewer. One of the most promising areas of this development are stereo glasses. For example, nVidia engineers released 3D shutter glasses with liquid crystal glasses a few years ago. To deflect light streams, the LED backlight of the LCD screen uses polarization filters. In this case, glasses are made without a special frame, in the form of a ribbon. The built-in lens consists of a wide array of translucent LED arrays that receive information from the control device.
Backlight Benefits
Compared to other backlight options, LEDs significantly improve the consumer qualities of television screens. First of all, the immediate characteristics of the image are improved - this is expressed in an increase in contrast and color reproduction. The RGB matrix provides the highest quality of color spectrum processing. In addition, the backlight of the LED screen is characterized by low power consumption. Moreover, in some cases, a reduction in electricity consumption of up to 40% is achieved. It is also worth noting the possibility of producing ultra-thin screens, which at the same time have a smallweight.
Flaws
Users of LED TVs have been criticized for the harmful effects of blue-violet radiation on the eyes. Also, bluishness is observed in the “picture” itself, which distorts the natural color reproduction. True, in the latest versions of high-resolution TVs, the LED backlight of the screen has practically no such defects. But there are problems with brightness control, which involves pulse-width modulation. You may notice screen flicker during these settings.
Conclusion
Today, the segment of TV models with LED technology is in its infancy. The consumer is still evaluating the possibilities and advantages that an innovative solution can provide. It should be noted that the operational disadvantages of LED backlighting do not confuse users as much as the high cost. Many experts consider this factor to be the main barrier to the wide popularization of the technology. However, the outlook for LEDs is still promising, as their cost will decline as demand increases. At the same time, other lighting qualities are being improved, which further increases the attractiveness of this offer.
