A battle for the title of best new television opened Tuesday at the Consumer Electronics Show, with titans fielding new slim, smart, ultra high-definition models.

LG Electronics fired an opening salvo with a new OLED television no thicker than four stacked credit cards.

The South Korean consumer electronics colossus opened a packed day of press conferences at the annual tech extravaganza in Las Vegas with a line-up that included an OLED Signature panel touted as "quite literally, a picture on glass."

The television measures an unprecedented 2.57 mm, LG Electronics USA marketing vice president David VanderWaal said during an on-stage presentation.

"Our passion and commitment for OLED has never been stronger," VanderWaal said.

"OLED TV is already recognized as the best TV ever."

OLED displays have pixels that emit their own light, while pixels in LCD TVs are illuminated by backlights.

OLED screens boast deeper blacks, allowing for a wider range of color than LCD displays. They also tend to come with higher price tags.

LCD televisions remain "the king of screens" with sizes trending up, according to the Consumer Technology Association, the trade group behind CES.

One in every five televisions sold this year is expected to be 50 inches or more, measured diagonally, and feature ultra high-definition 4K resolution.

- 'Premium' certification -

LG was among the TV makers here introducing new models that will come with a freshly minted Ultra-High Definition Premium Certification signalling that they meet standards freshly established by an alliance representing manufacturers, technology companies and studios creating content.

"The criteria established by this broad cross-section of the Ultra HD ecosystem enables the delivery of a revolutionary in-home experience," UHD Alliance chairman Hanno Basse said in a release.

"And, the Ultra HD Premium logo gives consumers a single, identifying mark to seek out so they can purchase with confidence."

Analysts told AFP they expected adoption of 4K ultra-high definition televisions to pick up speed this year as prices get in reach of more consumers and the displays become marketplace norms.

LG built Dolby Vision technology into its new televisions.

"Dolby Vision creates a picture so lifelike you will forget you are looking at a TV screen," Dolby Labs senior vice president Giles Baker said during the presentation.

Dolby Vision has been used in major films including box-office record-breaker "Star Wars: The Force Awakens," according to Giles.

The LG television line-up included "Super UHD" LCD displays as slim as 6.6 mm and a new flagship 8K television measuring 98 inches diagonally.

- Samsung steps up game -

Later in the day, leading television maker Samsung unveiled a new line of ultra-high-definition LCD televisions capable of not only streaming games or shows from the Internet but able to serve as command centers for smart home devices, from locks and lights to thermostats and appliances.

Samsung Electronics visual display business president Hyun Suk Kim pulled back the curtain on new SUHD Quantum Dot televisions that he said marked the "start of a new era of TV."

"This year we are focused on bringing the television experience into the future," Samsung Electronics America executive Dave Das said.

"The new SUHD TV is a giant leap forward in time."

New models have software designed to better consolidate traditional and online content, and remote controls that automatically detect and command accessories with no set-up needed.

Samsung's new SUHD televisions will also allow people to play more than 500 video games, including blockbusters such as "Assassin's Creed" streamed online in partnership with Sony's PlayStation Now service, without needing consoles.

- Smart home hubs -

The TVs will also act as command centers in smart homes by incorporating technology from Silicon Valley start-up SmartThings, which Samsung bought in 2014, allowing them to control devices synched to the platform.

"I think this is really a big step forward for opening up the market," SmartThings founder and chief Alexander Hawkinson told AFP.

"You can have a smart home basically for free as a starting point; it is pretty amazing."

SmartThings is based on open standards, letting tens of thousands of developers tailor applications to work with the platform.

"In 2016, we're going beyond anything we've done before to offer a remarkable synergy of design, engineering and craftsmanship," said Hyun Suk Kim.

- Sony streaming service -

Sony unveiled a new flagship LCD televisions and boasted that it is ramping the quality of displays with "high dynamic range" technology that appeared to be a rage at CES.

The Japanese consumer electronics and entertainment colossus said it has also broadened its line of ultra-slim Bravia televisions.

Sony also introduced an Ultra 4K streaming service that taps into the company's film and television library and is optimized for Bravia models.