The 26-year-old graphic designer of Nevanthon Road, Leicester was sentenced to life at the Old Bailey after being found guilty of murdering telephone executive Phillip Sherriff, 37, of Preston, Lancashire.
Judge Paul Worsley said that Charles would serve a minimum of 14 years.
The court heard that the attack happened at the BlackBerry event after jostling at the bar, when Charles grabbed the bottle from Sherriff's hand and broke it before slashing his neck.
Charles had claimed he was acting in self-defence, but the court did not agree.
Judge Worsley said: "This is a tragic case. Mr Sherriff may have pushed you in a crowded bar and made inoffensive remarks to a girl talking to you.
"You clearly became annoyed at what you perceived was the conduct of Mr Sherriff and lost your temper when he may have pushed against you at the bar."
He added: "You did not deliberately smash the bottle you used. I am satisfied you did not intend to kill Mr Sherriff and you were immediately remorseful."
Sherriff died four days after the incident at London's Pulse nightclub, having been attacked after Jessie J's performance.
On hearing of Sherriff's death, Jessie J said that she was "lost for words".
"All I can say is my thoughts, love and respects are with the family and children of the man who attended the gig last week who sadly lost his life... so sad."