District Judge William Ashworth, sitting at Thames Magistrates’ Court, told Gill-Webb: “Your intention was to target the highest-profile event at the London Olympic and put off Usain Bolt.

“The potential harm of triggering a false start was significant. By good fortune, you failed.

“You did, however, spoil the occasion for some spectators and tarnish the spirit of the Games.”

Gill-Webb will be electronically-monitored and be subject to a 7pm to 7am curfew. He was also ordered to pay a £1,500 contribution to costs.

The judge said: ``You suffer from bipolar disorder. At the time of the offence, you were in the throes of a manic episode. This made you over-confident and your behaviour risky.

“I have reduced your punishment to take account of the effects of your illness.”

Gill-Webb used an old ticket to get into the Olympic Park and then the stadium on August 5.

He hurled abuse at athletes, including Jamaican sprint star Bolt, and then threw a bottle on to the track as the final began.

It landed behind the lane markers and the world’s top sprinters as they exploded out of their blocks in the showpiece race.

Bolt, the world record holder and defending champion, won in 9.63 seconds, ahead of Jamaican team-mate and 2011 world champion Yohan Blake. The US’s Justin Gatlin, the 2004 100m Olympic champion, won bronze.

Gill-Webb was found guilty of intending to cause 100m finalists harassment, alarm or distress by using threatening, abusive or disorderly behaviour, contrary to Section 4 of the Public Order Act.

The judge said Gill-Webb's behaviour was ``serious'' enough to demand punishment but he thought he was unlikely to offend again.

The high profile nature of the incident and the fact that the world was watching were aggravating factors, along with the location from which the bottle was hurled, according to prosecutor Helen Shaw.

It was a “once-in-a-four-year event watched by millions of people around the world”, she said.

“Some of the people who were in that area missed the event and had paid up to £4,000 a ticket.”

Tom Barley, defending, said Gill-Webb risked inflicting “massive embarrassment on the country” by his behaviour.

He has since lost his job through the bad publicity triggered by the case and has two young children to look after, the court heard.

Mr Barley said: “He would have looked like a drunken yob on that occasion.”

Noting that alcohol did not have any influence, Mr Barley suggested that for someone dealing with a mental illness on a day-to-day basis, “it must have been the worst day for it to happen, in the 100m final”.

Gill-Webb is being treated for his illness.

The court heard that Gill-Webb pushed his way to the front of an exclusive seating area at the stadium and started shouting: “Usain, I want you to lose. Usain, you are bad, you are an arsehole”.

He then threw the plastic beer bottle as the race started.

Dutch judo champion and London 2012 70kg bronze medallist Edith Bosch who confronted him about the bottle throwing said the incident made her miss the race.

Gill-Webb was escorted from the stadium and arrested.

The court heard he used an old ticket to get into the Olympic Park, and then the stadium.

Police never found a ticket on him.

Witnesses saw Gill-Webb shouting at the finalists.

Student Farzin Mirshahi heard him yell: “Believe in Blake, no Usain”.

Her brother, Kiya Mirshahi, heard: “Usain, no, Justin, you are a druggie, believe in Blake, no Usain, no.”

Bolt and Blake, who won gold and silver in the race, said they had been unaware of the incident.

In interviews bronze medallist Gatlin said: “It was a little distraction and I didn’t know what it was.

“But when you’re in those blocks and the whole stadium’s quiet, you can hear a pin drop.”

He said the incident had not affected the race: “You just have to block it out and go out there and do what you got to do.”

Gill-Webb, who did not give evidence during his trial, originally denied throwing the bottle, but his DNA was later found on it.

He later said he could not remember the incident.