Why did quantum dots, which can solve the weakness of LCD picture quality, wait until this year to appear?

A new term for LCD TVs has entered the vision of many people - "quantum dot TV". At the exhibition, a few manufacturers also displayed their own quantum dot TVs. According to the American technology news website TheVerge, the research and development of quantum dot technology actually began two years ago. This is also a technology aimed at improving the weak points of LCD TVs such as "black is not black". It can achieve high-quality images similar to OLED at one-third of the cost.

Quantum dots are tiny crystals that are invisible to the naked eye and can improve the picture quality of liquid crystal televisions. Sony adopted quantum dot technology in some high-end TVs two years ago, and now manufacturers such as Samsung, LG and TCL have followed suit.

TV manufacturers hope to use the improved picture quality brought by quantum dot technology to encourage people to replace their existing LCD TVs in their homes in a few years. In addition, the advancement of quantum dot technology can also allow manufacturers to abandon the research and development of other more expensive TV technologies.

Although it has only recently been mentioned in the popular media, quantum dot technology is not a new invention. It was discovered 33 years ago by Russian scientists Alexander Efros and Aleksey Ekimov, along with Bruce, who was working on another transistor project at Bell Labs.

Bruce discovered that chemical reactions in solvents can produce tiny particles of different sizes, and through particles of different sizes, any color in the spectrum can be obtained. By adjusting the chemical equation, particles that emit colorful light such as blue, red, and green can be obtained.

In fact, in the manufacturing process of solar panels, different particles have been used to emit different colors of light. Quantum dots can improve the absorption of solar energy. In the field of medical imaging, the combination of quantum dots can also improve the effect of electron microscopy.

Quantum dot technology can solve a fundamental problem of modern LCD TVs - the color and picture quality of backlit LCD TVs are not as good as plasma technology or OLED (organic light-emitting diode technology).

The black of LCD TV is not a wonderful "inky black" and the colors are not bright. This defect of LCD TV is related to the process of how the backlight system lights up the pixels.

This was not a problem if CCFL (cold cathode fluorescent tube) was used as the backlight source. However, when the entire LCD TV industry switched to LED as the backlight source, black and picture quality problems began to arise. Since LED light sources can make TVs thinner and more energy-efficient, it is actually worthwhile to switch to LED backlight sources.

TV manufacturers have come up with various ways to solve the problem of LCD TVs' dark blacks and dull colors, such as reducing the backlight intensity for the black part of the screen, which can improve the picture quality contrast and make black no longer look gray.

The biggest highlight of quantum dot technology is that it can be used as an additional layer of film on the LED backlight to adjust the light passing through. Quantum dots can greatly improve the color gamut, and the cost of improving picture quality is only one-third of that of OLED TVs.

Some manufacturers researching quantum dot technology (including QDVision, which is working with Sony) have said that integrating quantum dot technology into existing LCD TVs will not incur excessive additional costs in the manufacturing process.

Quantum dot technology has entered small consumer electronic devices, including Amazon's Kindle Fire HDX, the world's first tablet to use quantum dots. In addition, Asus's laptop (Zenboox NX500) released last month also uses quantum dot film made by 3M.

There were rumors in the industry that the iPhone 6, released in 2014, would use quantum dot displays, but this did not become a reality. At this year's Consumer Electronics Show, people saw LG's quantum dot TV, and Samsung Electronics will also launch a number of quantum dot TVs later. However, the two companies had not yet started mass production of quantum dot TVs before the show.

Cannon, a TV industry analyst at technology market research firm IHS DisplaySearch, said that there is still a problem in promoting quantum dot technology, that is, it is difficult to manufacture quantum dot films for large-screen TVs. "The weakness of quantum dot technology is large size, which is why people have not seen a large number of quantum dot TVs on the market."

Quantum dot technology can improve the picture quality of LCD TVs, but why has it only been integrated into products today? This is not so much a technical problem as it is a problem of the technology route chosen by TV manufacturers. Before this, TV manufacturers targeted OLED TVs as an alternative technology to LCD TVs. OLED can greatly improve picture quality, but its high cost has not been reduced.

Analyst Cannon said that OLED TVs can bring a huge improvement in picture quality, but the efforts of manufacturers such as Samsung and LG have not been successful. For example, LG Electronics, which has been promoting the advantages of OLED before, also launched its own quantum dot TV at this year's Consumer Electronics Show. At least for now, quantum dot TVs will coexist with OLED.

In addition to the evolution of television technology, the emergence of quantum dot technology is also related to its production. In the first half of this year, Dow Chemical will open a new factory in South Korea to produce quantum dot films for LG Electronics or other companies.

It should be noted that Dow Chemical does not use cadmium materials. This material has been banned in many countries due to its toxicity. In the past, cadmium was a key material in the manufacturing process of quantum dot films. However, Dow Chemical and its partner Nanoco have developed a new process to eliminate cadmium in quantum dot products.

Another unavoidable question is the cost price of quantum dot TVs and how they compete with existing LCD TVs. When Sony launched its first quantum dot TV, the entry-level model was priced at $4,999. In fact, this entry-level model integrates quantum dot technology into Sony's high-end 4K LCD TVs.

Cannon analysts said that this year other manufacturers will follow Sony's lead and integrate quantum dot technology into ultra-high-definition TVs, and the price will increase by 30% to 50% compared with existing LED-backlit LCD TVs. For consumers who are waiting for holiday discounts to buy large-screen LCD TVs, quantum dot TVs are still a bit highbrow, but quantum dot technology means that people will be able to get TV high-definition quality close to OLED for less than the price of a car.

As a winner of Toutiao's Qingyun Plan and Baijiahao's Bai+ Plan, the 2019 Baidu Digital Author of the Year, the Baijiahao's Most Popular Author in the Technology Field, the 2019 Sogou Technology and Culture Author, and the 2021 Baijiahao Quarterly Influential Creator, he has won many awards, including the 2013 Sohu Best Industry Media Person, the 2015 China New Media Entrepreneurship Competition Beijing Third Place, the 2015 Guangmang Experience Award, the 2015 China New Media Entrepreneurship Competition Finals Third Place, and the 2018 Baidu Dynamic Annual Powerful Celebrity.