Im set the first world record of the London Olympics on Friday, breaking his own mark in the 72-arrow event and helping South Korea set a team record in the opening round. He broke the record he set in Turkey in May by three points with a score of 699, hours before the opening ceremony of the 2012 Games.
"This is just the first round, so I will not get too excited by it," said Im, who has 10 per cent vision in his left eye and 20 per cent in his right.
He combined with Kim Bub-min and Oh Jin-hyek, breaking the record for 216 arrows with a score of 2,087. That was 18 better than the mark South Korea set in May.
The 26-year-old Im does not wear glasses in competition, saying he relies on distinguishing between the bright colours of the target. He won gold in the team event at the 2004 and 2008 Olympics.
South Korean coach Jang Young Sool also didn't seem too impressed by his team's accomplishment. He said his archers must get ready their next test.
"We will have a day of rest now and prepare for tomorrow," he said of the gold-medal match Saturday.
France finished second in the team event, followed by China and the U.S., which was ranked No. 1 coming into the event. The U.S. men beat South Korea last October in London.
Brady Ellison, world No. 1 individual archer, said the conditions were ideal Friday and he wasn't surprised the individual world record fell.
"I don't think you get those types of scores anywhere if the weather wasn't just perfect today," the American said. "Korea shoots good, and if you look at the scores, they're always top in the ranking round."
Also Friday, the American women's team scored a surprising second-place finish. Miranda Leek, Jennifer Nichols and Khatuna Lorig scored 1,979 points with 216 arrows. They were 14 points behind South Korea, which scored 1,993 points.
The U.S. team is ranked No. 6 in the world and qualified for London just last month in Utah.
Lorig, competing in her fifth Olympics, finished fourth in the individual event with 669 points on 72 arrows. She trailed archers from South Korea and Taiwan, all tied at 671 points.
"The ranking round is just a practice," she said. "As a team it is going really well. There is great team spirit and everybody is happy."
Lorig is a naturalized American who's represented the Unified Team of the former Soviet Union, the Republic of Georgia and the U.S. She coached archery to Jennifer Lawrence, star of "The Hunger Games."
Spectators hoping to catch a glimpse of the action Friday were turned away from Lord's cricket ground.
Preliminary rounds were listed as non-ticketed, so several thousand spectators showed up at the venue expecting to get in for free.
A spokeswoman for the London Games organizing committee said tickets were not advertised or sold for the qualifying events and "we have always made it clear" that the early competitions were not open for spectators.