Shenzhen Enrich Electronics Co., Ltd

Favorite  |  Set Home
skype: live:cassie_1191
QQ: 2850818618
Company News >> 20-year evolution of LCD backlight technology 12th,Nov,2018
                                            Around 1998, LCD display technology began to appear. Now in 2018, after 20 years, LCD display technology has become an inseparable part of people's daily life. The backlight technology of LCD has also been evolving. From CCFL backlight to current quantum dot backlight, to future Mini LED backlight, the change of technology makes the display effect of LCD continue to improve.

Nowadays, LCD technology faces many challenges. There are Micro LED display technology under AMOLED and laser large screen technology. Whether it is large screen market or small screen market, LCD is facing unprecedented pressure. However, it is too early to say that LCD loses its future. Today, we will take a look at the ins and outs of LCD backlight technology. We also look forward to how LCDs can continue to maintain their competitive edge in the future competition with the support of different backlight technologies.


CCFL cold cathode fluorescent lamp

First let's look at the CCFL backlight. CCFL is the abbreviation of cold cathode fluorescent lamp. Such a backlight is a light source that emits light by exciting a phosphor by a cold cathode gas discharge. A thin gas with a small amount of mercury will ionize at a high voltage, and a secondary electron emission by the ionized gas will bombard the mercury vapor, causing the mercury vapor to be excited, emitting ultraviolet rays, and the ultraviolet light excites the phosphor layer applied to the wall tube, so that It shines. Its biggest advantage is its high brightness. The disadvantage is that it consumes a lot of power and is bulky.


The display with CCFL backlight is larger in size and consumes more energy.

LCD monitors using CCFL backlights are relatively thick and relatively expensive. With the advent of LED backlights, CCFL backlights have gradually withdrawn from the historical arena, and it is now difficult to find such products. There are also such new products on the market.

LED backlight: replace the true power of CCFL

LED backlight technology is currently the most widely used technology. LEDs are light-emitting diodes, and much more are seen in the field of lighting. Power saving, small size, long life, and low cost, it can be said that this kind of light source is used in the field of LCD backlighting. It is a natural fit to defeat the CCFL backlight.


LED backlight strip

In particular, the "simplified" LED backlights used now further reduce the cost. LCD backlights require a white light system, while RGB LEDs can make up white light. Such a system is theoretically the best, because the system has three primary colors, so the display color gamut is more powerful. However, the RGB LED backlight system is complicated and costly, and is generally only used on high-end LCD displays.


LCD display structure The backlight is located behind the LCD panel

Now the low-end LCD display uses blue LED mixed yellow phosphor to form white light. This white light has more blue light and less performance for red and green. Therefore, the color gamut has not been very powerful. And this backlight system puts the LED light bar at one end of the display, and then uses the light guide plate to form a surface light source, which is a common WLED backlight.

At present, LCDs mostly use LEDs as backlights, high-end products use RGBLEDs, and low-end products often use WLED backlights. LED can replace CCFL successfully. Its long life is stable and its operating current is small, so the power consumption is lower than that of traditional light source. LED's energy-saving and durable features combined with its slim size meet the current concept of ultra-thin environmental protection for display users.

Quantum dot backlight upgraded color

Quantum dot technology has been heard by many people. In fact, quantum dots are a kind of nano-scale materials that can emit light. Under the excitation of blue LEDs, quantum dot particles of different diameters can emit different pure color lights. Therefore, these characteristics can be Application in the field of liquid crystal panels.


Blue light-excited quantum dot material emits purer three primary colors

There are already many quantum dot products, both in the display field and in the TV field. Quantum dot products have already appeared, and as technology advances, the cost is also reduced. The premium of LCD dot-backlit LCD display products compared to LED backlight products is not high.


Structure diagram of quantum dot backlight and comparison with OLED panel

Therefore, although the quantum dot propaganda is powerful, it is essentially LCD display technology, which is only an improvement of backlight technology. Just like the concept of "LED TV" used to say a lot, the essence is just to change the CCFL backlight into LED backlight.

Mini LED backlight Ultimate form?

Now there is a Mini LED backlight. This kind of backlight is not a new technology, it is still the category of LED backlight. Compared with the traditional blue LED light source mode, the size of the Mini LED backlight is very small, so it can directly RGB three-color LED module, thus achieving the effect that the RGB three primary colors are not missing.


Mini LED backlight can further enhance the display color effect

Why do you have to study Mini LED backlight technology with quantum dot technology? One is because the emergence of AMOLED technology makes the effect of quantum dot backlight technology unsatisfactory. One is because the development speed of LED technology has been rapid in recent years, the size of LED modules has been shrinking, and the cost has dropped rapidly. The popularity of Mini LED backlight technology has begun to have a timetable.


Display products with Mini LED backlight

In fact, fundamentally speaking, self-illumination technology is the ideal mode for display technology. Self-illumination naturally has no problem of viewing angle, and is more suitable for surface display and flexible display. However, from the beginning of plasma display, self-illumination technology has been facing two major problems, the first is life, and the second is cost. Because it is self-illuminating, the luminescent material is easily damaged, so that the life of the panel is problematic; and the self-illuminating material is expensive, resulting in an expensive overall price of the product, which is also an important reason why self-illuminating technology is difficult to popularize.

In fact, AMOLED display technology is still facing such technology and market dilemma. Although LCD technology is not an ideal model, it has improved speed, low cost, and the industry is very mature. Therefore, under the challenge of new technology, it will not be as fast as the CRT display technology. Perhaps with the addition of Mini LED backlight technology, LCD technology can also challenge the status of AMOLED technology and continue to be the leader in the big screen market.

Online service

Skype: live:cassie_1191 2850818618