To most people, Darth Vader is the tall, scary half-robot half-human dark lord from Star Wars.

But in one Tennessee hospital, Vader is a surgical technician, helping to keep people alive, unlike his namesake.

Darth Vader Williamson, 39, is a surgical technician at St Francis Hospital-Bartlett in suburban Memphis.

His parents gave the name to him after his birth in 1978, less than a year after the original Star Wars film was released.

"When I was born my mother wanted me to be named Junior, after my father. But my dad was a 'Star Wars' buff," Williamson said. "He was so enamoured with the character Darth Vader that he was like, 'This would be one bad (good) name for our son.'

"Under the effects of anaesthesia, (my mother) would have agreed to anything. She was like, 'Yeah, OK, fine.' And ... afterward, she was like, 'Uh, what have we done?'"

Williamson says he didn't like his unusual name as a child. Kids teased him on the playground. Teachers giggled while calling on him in class.

"At first I was like, 'Man, what have you all done to me?' he said. "But once I got through high school and the girls were digging it, I thought, 'I can use this to my advantage.'"

The name has brought some unexpected positives too, a state trooper pulled him over for speeding in 2016 and was left stunned by the name on Williamson's license that he let him go with just a warning.

"Some people go overboard," Williamson said. "I've been asked for autographs. I've been asked to take pictures. I've had people say, 'Hey, the opening for the new 'Star Wars' is coming out. Can you go with me?'"

Despite the name, Wiliamson isn't a massive fan of the Star Wars saga. He hasn't watched a Star Wars movie since 1983 when Return of the Jedi was released.

The biggest issue with his name is that Vader isn't his favourite character from Star Wars, he prefers bounty hunter Boba Fett.