US businessman Tom Petters has been sentenced by a federal judge to 50 years in prison for his role in a $3.7bn (£2.4bn) fraud.

美国商人汤姆·培特因一起37亿美元的诈骗案被某联邦法官判处有期徒刑50年。

Mr Petters' Petters Worldwide Group once owned Polaroid

The 52-year-old former owner of Polaroid was found guilty on multiple counts of fraud and money-laundering last December.

The case involved a so-called Ponzi scheme, the same fraud that Bernard Madoff was convicted of.

Mr Madoff was jailed for 150 years last summer for his role in a $65bn scheme.

"This was a massive fraud," said US District Judge Richard Kyle.

"Tom Petters was at the front and centre of every stage. [He] was captain of the ship. [The fraud] would not have happened without his direction."

A Ponzi scheme（庞氏骗局） is a fraudulent（不正的，欺骗性的） investment that pays out（付出，报复） to existing investors¹ money paid in by new investors, rather than real profits.

It is named after Charles Ponzi, who notoriously（恶名昭著地，声名狼藉地） used the technique in the US in the 1920s.