Last year television’s buzzword was 4K, with the emphasis on ultra-high definition and crystal sharp pinpoint clarity. This year the emphasis is the same, but the buzzword has changed to quantum dots, and LG are leading the way by already announcing the first quantum dot TV to be manufactured.
What is Quantum Dot Technology?
Quantum dots is a complex nanotechnology that allows pictures to look even clearer and brighter than 4K, but this doesn’t mean that we’ve seen the last of 4K. What consumers are hoping for are more affordable 4K sets and content to watch on them, and they should get their wish, although probably not in the very immediate future.
As for the quantum dot technology, the way it works is by harnessing light-emitting nano crystals that are 100,000 times smaller than the width of a human hair. These crystals emit different colours depending on their size, which range from two to 10 nanometres. Once a film of quantum dots has been added in front of the LCD backlight on the TV, the reproduction rate of the picture increases by 30% and overall brightness is significantly improved.
“Quantum dot’s vibrant and vivid colour reproduction capabilities brings LG’s LCD TVs to the next level when it comes to picture quality,” said In-kyu Lee, senior vice president and head of the TV and monitor division at the LG Electronics Home Entertainment Company.
Who else uses it?
Quantum dot technology is not actually a new science, as there are already a products on the market that feature quantum dot displays. These include Amazon’s Kindle Fire HDX. However, the problem with using quantum dots is that you need cadmium, which is restricted in Europe as it is on the European Union’s Restriction of Hazardous Substances (RoHS) regulation list.
Is it environmentally friendly?
To eliminate this problem, LG has been working with researchers to come up with a cadmium-free TV that uses quantum dots. They also state that their 4K TVs will be manufactured to be environmentally friendly and not use any other heavy metals that are considered to be toxic or harmful.
However, not everyone is convinced that cadmium is the bad guy when it comes to the environment, and it is also the best compound for producing the colors and brightness of the picture.
“There are only a couple of materials that deliver on the promise of quantum dots,” says QD Vision’s Volkmann. “The other is based on indium. Cadmium is superior with respect to delivering higher-quality color, meaning a broader color gamut. But also much more energy-efficient at converting blue light to other forms of light that allow you to fill out that spectrum. Cadmium is under observation by different regulatory agencies around the world, but it turns out indium is too.”
“Cadmium-based materials have a narrower spectral width,” says Nanosys’s Hartlove. “More pure color. And what that means is the other things the system has to do in order to keep that color pure, the burden on the rest of the system is reduced.”
Cadmium could actually be a better choice than indium as it turns out the cad selenide crystal used in quantum dots isn’t as toxic as pure metallic cadmium, and they are more efficient at producing color.
“The type of power we generate in the US from coal-based power plants throws cadmium into the atmosphere,” says Hartlove. “That’s one of the byproducts of burning coal. And you look at the net cadmium content over this whole lifecycle, and it turns out that cadmium sequestration is actually net better for the environment.”
LG revealed two quantum dot TV’s at CES 2015, a 55-inch and 65-inch ultra-high definition, although it did not say how much it would cost.