Irvine-based Vizio Inc. has regained the title as the top seller of liquid-crystal display TVs in the U.S.

Vizio sold 1.2 million LCD units in the first quarter for a market share of 18.7%, edging out Samsung Group, which had held the lead since the second quarter of 2011.

The South Korea-based consumer electronics maker sold 1.1 million LCD TVs in the quarter for a market share of 17.8%, according to Englewood, Colo.-based market tracker IHS Inc.

LG Electronics Inc. was a distant third, selling 657,000 TVs in the first quarter for 10.1% of the market.

Vizio has typically done well in the first quarter following the holiday shopping season as some cash-strapped consumers may have delayed TV purchases late last year, according to IHS TV systems and technology analyst Tom Morrod.

“This is at least a two-year trend Vizio peaked in the first quarter against Samsung,” said Morrod, a senior principal analyst in the company’s London office.

Flat-TV sales, made up mostly of LCDs, are expected to decline 5% to 37.1 million units in the U.S. this year. That would mark the first drop since flat TVs debuted more than a decade ago.

About 6.5 million LCD TVs were sold in the March quarter, down 14% from a year earlier.

Vizio has prepared for the downturn.

It debuted a new line of desktop computers and notebooks last week at a New York press event and entered the tablet market last year, though it’s too early to gauge the company’s success in that segment.