Can eliminate CCFL? Analysis of LED backlight LCD TV

From black and white to color, from flat to flat, the TV in the China short span of thirty years has been rapid development. Recently, there are color TV manufacturers called the LED, flat trend, the slogan, then LED will be a new big flat-panel TV upgrade it?

For LED, the author here is necessary to give you a brief introduction. LED is the abbreviation of light-emitting diode, the English name is Light Emitting Diode. In daily life, mainly used in a variety of household appliances, such as lights, car rear fog lights, etc.. In the flat-panel TV, appeared as a backlight upgrade, it usually refers to the LCD TV, because in the flat-panel TV, LCD TV only need backlight, and plasma TV is self luminous, if to the LED crown "flat trend" of the title, this stage is a bit too large, plasma may: dissatisfaction with the camp.

Challenges facing CCFL

At present, most of the LCD TV is the use of CCFL backlight, CCFL cold cathode fluorescent lamp is short, English called Cold Cathode Fluorescent Lamp, is the most mature in the back light at this stage, in addition to the use of the LCD TV, LCD, DVD is portable, aircraft, TV, GPS display, palm on the computer game machine and industrial instruments display backlight as above.

Most LCD monitors use CCFL backlight

With the rapid development of backlight technology, LCD cold cathode fluorescent lamp through the test of time (CCFL) backlight system also began to face many challenges, including LED (light emitting diode) is the most popular one, the current line of flat-panel TV brands have launched LED backlit LCD TV, such as SONY X4500 series, SHARP XS1A the latest series, Samsung will launch of the 9 series and so on. In addition to LED, CCFL backlight system, there are many other competitors, such as SONY's latest HCFL (Hot Cathode Fluorescent), can effectively reduce power.

The cause of the rise of LED backlight

An important factor in the rise of LED backlight and the end face of the European Union is the implementation of the RoHS directive. The Directive provides for the elimination of lead, cadmium, mercury, hexavalent chromium, polybrominated biphenyls and polybrominated diphenyl ethers (PBDEs) in electronic devices sold in EU Member States since July 1, 2006. Mercury is the main component of CCFL and other types of fluorescent lighting.

LED lights do not use mercury

In the CCFL lamp, the need for mercury vapor in the electric field of the lamp is excited to produce a luminescence effect, so green, environmental protection has become a major cause of the rise of LED backlight. However, the current CCFL lamp suppliers have reduced their mercury content in the fluorescent tube, and also the development of mercury free products.

LED advantage relative to CCFL backlight

The current LCD TV market, in addition to several high-end products, the mainstream of the backlight of LCD TV are used in CCFL, CCFL's advantage is very obvious, such as the application of mature, affordable, even if it is not good at color, can also be improved by coating CCFL to achieve wide gamut effect. So LED as a new generation of backlight system, relative to the CCFL backlight in the end what is the absolute advantage?

Advantage one: Environmental Health

In the CCLF cold cathode fluorescent lamp as a backlight source of LCD, one of the main elements can not be missing is mercury, which is familiar to the mercury, which is undoubtedly harmful to the human body. Although the manufacturers have been trying to reduce the mercury content in the fluorescent tube, but completely mercury free fluorescent tube will bring some new technical problems, temporarily not see the prospects for realization. The anti LED backlight, its advantage is completely free of mercury, in line with the green fashion.

Advantage two: saving energy

LED backlight very power-saving. Its power consumption is lower than the CCFL cold cathode backlight. LED internal driving voltage is much lower than that of CCFL, power consumption and safety were better than that of CCFL (CCFL AC voltage requirements are relatively high, when starting up to 1500 ~ 1600 Vac, and then to 700 or 800Vac), while LED only need 12 ~ 24Vdc or lower voltage can work.

The efficiency of LED combining light to the light guide plate is higher than that of CCFL

In addition, although the luminous efficiency of CCFL is not inferior to LED, but because CCFL is scattered light, in the light of the process of waste a lot of light, so that it appears to be more efficient LED light. Due to high efficiency, can reduce the number of the LED lamp, the design can be more reasonable, but also reduce the exposure.

Advantage three: longer service life

In general, the LED backlight source life longer than CCFL. Different CCFL rated service life (Ban Liang) in 8000 ~ 100000 hours, while the LED backlight can reach CCFL about two times. And in order to enhance the performance of the use of improved design of CCFL backlight life will be lower.

In addition, due to the reasons for the circuit design, the use of LED backlight LCD volume is expected to be more compact, and the cost of circuit design will be greatly reduced.

LED the problems faced in the process of popularization

Through the above analysis, we can see that compared to the CCFL backlight, LED backlight has superiority in environmental protection, There is nothing comparable to this gamut, energy saving, life and other aspects, so is LED is not able to quickly replace the CCFL backlight system, become the mainstream? I believe that, although the LED backlight technology has a lot of,