It's easier than ever to make big TVs. Each year brings a new record size and price tag for TVs that have stretched into triple-digit inch territory. There's been a simultaneous quest to be the thinnest TV, a metric that's great to chase on phones and tablets, but arguably less important for something most people set down and don't touch for years at a time. Not to be outdone, TV makers have added swooping curves to the screen, and crammed more pixels in the same amount of space — even if barely anyone is making movies or TV shows to view at that resolution

It's still hard to make a really good, really big TV that normal people can buy

With all these advances, it's still really hard to make really good, really big TVs that normal people can buy. To help solve that, another arms race quietly began almost two years ago and has become a battleground at this year's Consumer Electronics Show. It's still about size, just for something you can't see: quantum dots, extremely tiny crystals that promise to improve the color and efficiency of LCD TVs. Sony started including them in some of its high-end sets two years ago, and now others including Samsung, LG, and TCL are following suit. They hope the jump in quality will be big enough to get you to upgrade the set you bought just a few years ago. What's more, it could bail them out of investing in competing technologies that have proven difficult and expensive.

While they are a recent addition to TV sets, quantum dots are not a new invention. They were discovered 33 years ago by Russian scientists Alexander Efros and Aleksey Ekimov, as well as by Louis Brus, who was working on a completely separate project at Bell Labs to improve transistors. Brus discovered that a reaction in solvents created particles of different sizes, and that depending on the size, you could achieve any color in the light spectrum. By fine-tuning the formulation, it's possible to grow dots that glow blue, red, green, and more colors depending on their size. That color range has proven useful for the production of solar cells, where quantum dots have been used to increase energy absorption, as well as in medical imaging, where mixtures of quantum dots have helped improve electron microscopy.

Quantum dots promise to solve a fundamental problem with LCD TVs

Quantum dots promise to solve a very fundamental problem with modern LCD TVs, which is that the range of colors on LED-backlit sets are simply not as good as the ones on plasma and OLED TVs. Blacks don't quite possess that wonderful inkiness, and colors aren't as vivid. Much of this is due to the backlighting systems, and how they illuminate the pixels, a process that requires blue light to make it through filters to turn white (which results in undersaturated reds and greens). This wasn't a problem when LCD TVs were using CCFL lights to illuminate those pixels, but for nearly the entire industry, the jump to LEDs was worth it, allowing for TVs that were thinner and more energy efficient. TV makers have also tried to work around the black issue by dimming the backlight in dark areas of the screen, something that increases the contrast and makes blacks look less grayish.

The allure of quantum dots is that they can be added as a layer on top of an LCD TV's LED backlight to fine tune the light that makes it through. That can dramatically improve the color gamut, and do it at about a third of the cost of producing OLED displays. Makers of the technology, including QD Vision (which supplied Sony with quantum dots), also promise that this can be added to TVs without drastically changing how they're manufactured.

Quantum dots have already made their way into displays on smaller gadgets, including Amazon's Kindle Fire HDX, which was the first tablet to use the technology. They also ended up in Asus' Zenboox NX500 notebook, which was released last month and uses a quantum dot film made by 3M. There were even rumors of quantum dots arriving in Apple's iPhone 6 display last year, but that didn't pan out.

At this year's CES, we've already seen one quantum dot set from LG, which is set to be joined by a trio of TVs from rival Samsung. Neither company was making quantum dot TVs ahead of the show. One of the holdups, says Paul Gagnon, the director of TV research at IHS DisplaySearch, is that it hasn't been quite as easy to make the quantum dot film for big screens. "The one thing quantum dots don't do well is scale with size," he says. "It's why you haven't seen many quantum dot TVs yet."

"OLED was going to be this leap forward in color, and for Samsung that fell through."

Why quantum dots are only now starting to make their way into more and more TV sets has less to do with any technological breakthrough than being a Plan B. Many TV makers initially turned to OLED displays as a way to improve the way TVs looked, but ran into issues mass producing them, a problem that was compounded in the shift from 1080p to 2K, 4K, and beyond. "OLED was going to be this leap forward in color, and for Samsung that fell through. They backtracked into research and development," Gagnon says. The same goes for LG, which went from trumpeting the benefits of OLED to announcing its own quantum dot set for this year's CES, which will coexist with its OLED sets — at least for now.

Alongside these changes in TV manufacturing, there's also been a push to bolster quantum dot production. Dow Chemical plans to open up a new factory in South Korea in the first half of this year that will supply LG, and potentially others, with quantum dots that are made without cadmium. The metal, which is also used in some paints, faces bans in several countries due to its toxicity. Cadmium has long been crucial to the production of quantum dots, though Dow and its partner Nanoco say they have come up with a way to produce the dots without any traces of it in the final product.

Another lingering question is just how much this new crop of quantum dot TVs will cost versus existing sets. When Sony's first quantum dot set came out, the entry-level model was $4,999, but the technology was essentially bundled in with 4K TV as one of the company's higher-end models. Gagnon says the same thing is expected with sets from other manufacturers this year, with quantum dot sets running somewhere in the ballpark of a 30 to 50 percent increase over comparable LED-backlit LCD TVs. That may be hard to swallow for the crowd that buys their TVs from a Black Friday flyer, but could also mean getting close to OLED-like quality in a big set that doesn't cost as much as a car.

Correction: Nanoco's production process is cadmium-free. This article originally stated that there were traces of it left over.