After years of development, the LED display industry has gradually matured and is expanding in the application field. From the statistics of recent years, the annual output value of the domestic LED industry has exceeded 140, and the number of LED display screens has been fully proved. From a market perspective, LED backlight technology does have its advantages.
With its unique and overwhelming advantages, LED backlight technology has gradually shown a strong application prospect. So, today, Nan Nan will give you an in-depth analysis of LED backlight technology compared with CCFL backlight technology. What are the advantages of LED backlight technology, why is it particularly popular in the display market?
LED backlight technology: Ten leading LEDs as the backlight of LCD, compared with the traditional backlight technology, in addition to the advantages in the color gamut range, there are many unique advantages, summarized into ten aspects:
1) LED backlights have a better color gamut. Its color expression is stronger than CCFL backlight, which can make a good complement to the liquid crystal technology with insufficient display color, and the color reproduction effect is better.
2) LEDs can last up to 100,000 hours. Even if it is used continuously for 10 hours every day, it can be used continuously for 27 years, which greatly prolongs the service life of LCD TVs, and has the advantage of overwhelming plasma technology.
3) The brightness adjustment range is large. It is easy to achieve LED power control, unlike the minimum brightness of CCFL. Therefore, it is easy for the user to adjust the brightness of the display device to the most pleasing state, whether in a bright outdoor or a black room.
4) Perfect motion picture. The flashing illuminating frequency of the conventional CCFL lamp is low, and the dynamic scene may cause the picture to jump. The LED backlight can flexibly adjust the lighting frequency, and the frequency is much higher than the CCFL, so it can perfectly display the moving picture.
5) Real-time color management. Since the red, green and blue colors are independent of each other, it is easy to precisely control the current display color characteristics.
6) The white balance of the backlight can be adjusted while ensuring the overall contrast. When the user's video source is switched between the computer and the DVD player, the white balance can be easily adjusted between 9600K and 6500K without sacrificing brightness and contrast.
7) A continuous array of light sources can be provided for large screen sizes. LED is a kind of planar light source. The most basic light-emitting unit is a square package with a length of 3~5mm. It is easy to combine into a surface light source with a certain area. It has good brightness uniformity. If it is used as backlight of LCD TV. The source, the required auxiliary optics can be made very simple, and the screen brightness uniformity is even better.
8) Security. The LED uses a low voltage power supply of 5~24V, which is very safe and the design of the power supply module is quite simple.
9) Environmental protection. LED light source does not produce any radiation, and there is no toxic substance such as mercury. It can be said to be a green light source.
10) Earthquake resistance. The planar structure gives the LED a solid internal structure and excellent shock resistance.
Advantages of LED backlight technology: Energy-saving and environmentally-friendly LED backlight is the abbreviation of Light Emitting Diode, which can directly convert electrical energy into light-emitting device. As a new generation of LCD backlight panels, it has outstanding features of low power consumption, high brightness and long life.
As the LCD backlight, CCLF (Cold Cathode Lamp) is the main element that cannot be lacking. This is the mercury that everyone is familiar with, and this element is undoubtedly a substance harmful to the human body.
Compared with the traditional CCFL backlight, the LED backlight can save more than 40% energy compared with the general-grade CCFL backlight civilian-grade products, and has a substantial improvement in energy saving. In addition, mercury in CCFL backlights is a substance that is quite harmful to the environment, but LED backlights do not contain such harmful substances, which is more environmentally friendly.
The second advantage of LED backlight technology: thin and elegant LED backlight is composed of a large number of grid-like semiconductors, each with an LED semiconductor in the "grid", so that the planarization of the light source can be successfully achieved. Its planarized light source not only has excellent brightness uniformity, but also does not require complicated optical path design. In this way, the thickness of the LCD can be made thinner and lighter, while still having higher reliability and stability.
Conventional CCFLs are tubular light sources, and the uniform distribution of the light they emit to each area of â€‹â€‹the panel requires relatively complex auxiliary components. The thickness of the screen is also difficult to control, and as the panel increases, multiple light sources must be used, which further exacerbates the complexity and cost of the design, which is more sensitive to large-screen LCD TVs. For example, for LCD or TV products above 50 inches, the cost of direct-lit CCFL backlight modules may account for more than half of the panel cost.
The third advantage of LED backlight technology: ultra-wide color gamut LED backlight has more uniform illumination, and is far superior to CCFL backlight in color expression. It can make a good complement to the liquid crystal technology with insufficient display color, and easily realize the wide color gamut of NTSC 118% or higher, so that the liquid crystal display can truly restore the vivid colors in the colorful nature.
The traditional CCFL backlight technology, due to the limitation of the fluorescent material, the red light of the lamp is weak, and the color filter of the matched color filter is also poor. It can only achieve NTSC 65-75% NTSC color area, even if By adopting the improved CCFL light source, it can only achieve a color gamut range of about 90% of NTSC, which affects the image quality.
The fourth advantage of LED backlight technology: the long life LED backlight can last up to 100,000 hours, even if it is used continuously for 10 hours every day, it can be used continuously for 27 years. Therefore, after using the LCD backlight or the LCD TV for a long time, the brightness of the backlight is attenuated better than the CCFL backlight.
The service life of ordinary CCFL backlights is about 25,000 hours. The luminous life of the latest top CCFL backlights is only 60,000 hours. At the end of the service life, the brightness of LCDs will drop significantly, and the CCFL backlight modules of LCDs have to be replaced. The LED backlight has no such problem at all. At present, the actual life of the white LED backlight is 50,000 to 100,000 hours, which is basically consistent with the service life of the LCD display, and there is potential for further improvement. Even if it is used 24 hours a day, it is enough to use for 5 years. As a result, LED backlights have a much longer luminosity than CCFL backlights.
The fifth advantage of LED backlight technology: the high brightness LED backlight has a large brightness adjustment range, which can flexibly adjust the illumination frequency, and the frequency is much higher than the CCFL backlight, so it can perfectly display the motion picture. However, the flashing light emission frequency of the conventional CCFL backlight tube is low, and when a dynamic scene is displayed, a jump picture may be generated.
As a passive display device, the liquid crystal display does not emit light by itself. It relies on a backlight to display light through the display panel to display a graphic image. Therefore, the backlight technology directly affects the picture quality of the LCD TV. Conventional liquid crystal displays usually use cold cathode fluorescent lamps (CCFL) as a light source, and it is CCFL that causes the liquid crystal display to be not rich in color and poor in color reproduction.
The LED backlight technology has six advantages: the adjustable white balance LED backlight can adjust the backlight white balance while ensuring the overall contrast. When the user's video source is switched between the computer and the DVD player, the white balance can be easily adjusted between 9600K and 6500K without sacrificing brightness and contrast.
A white balance adjustment method based on RGB three-color LED backlights, comprising: when the display is independently operated, when the backlight is adjusted to a new brightness level, the value of the temperature sensor on the backlight board is read, if the actual value of the current color sensor Larger than the standard value, the current duty cycle of this lamp is reduced a little. Conversely, the current duty cycle of such a lamp is increased a little. In order to obtain the drive current duty cycle and the standard value of the color sensor, a particle swarm algorithm is used. The advantage is that the white balance adjustment at a wide temperature is automatically performed, the response speed is improved, the labor intensity is reduced, and the efficiency is improved.
The advantages of LED backlight technology: ultra-high contrast LED backlight can further improve the uniformity of illumination compared with traditional CCFL fluorescent backlight. With LED support for multi-point control, the contrast of LED backlight display can be greatly increased to 1 million: 1 height. .
In simple terms, the contrast is the same as the full-on/full-off contrast, which is also the ratio of the brightness displayed by the test monitor to the all-white signal to the brightness of the all-black signal display. Unlike the full-on/full-off contrast, the display adjusts the brightness of the backlight so that the brightness displayed when receiving an all-white signal is higher, and the brightness of the receiving all-black signal display is lower, which in turn leads to a larger Value.
In summary, the cost of LED backlights and traditional CCFL backlights, in the LED backlight technology has become mainstream today, with the advantages of mercury-free, low energy consumption, good color, long life and many other consumers have been Recognition. At the same time, the cost of small-size LED backlights has gradually dropped to a price very close to CCFL backlights. For consumers, having an energy-saving, environmentally-friendly and affordable product will naturally be sought after by consumers.
With the pull of the liquid crystal display market, the LED backlight industry has presented a booming scene. With continuous improvement in display technology, the huge LED market is destined to develop into a huge industry.