Someone in the crowd at Wembley pointed the laser in Schmeichel’s face as he prepared for Harry Kane’s penalty attempt.
The Dane saved the England captain’s shot in overtime but Kane hit on the rebound to send the Three Lions to the final with a 2-1 victory.
Former England star Stan Collymore led the criticism on social media, writing: “If anyone has pointed a laser pen at Schmeichel, he wants to ban him for life. “
And several fans added to the post, one writing: “Whoever showed that laser in Schmeichel’s face deserves a permanent ban from Wembley and other games in England.” “
Another said: “Whoever made that laser pen shine on Kasper Schmeichel’s face wants to ban it for life. “
The laser was not the only controversy surrounding the sanction. Denmark did not believe Joakim Maehle’s tackle on Raheem Sterling was enough to warrant a penalty and another ball was on the pitch by the time it happened.
Danes manager Kasper Hjulmand expressed his frustration after the game.
He said: “It was a penalty that shouldn’t have been a penalty. This is something that annoys me at the moment. We are very disappointed.
“You can’t pass the ball on the pitch which has so much influence on the game.
“I know it sounds weird right now, but I can’t help but have these feelings. One thing is to lose a game, it happens, but losing that way is disappointing because these guys fought a lot.
“It’s bitter, but we have to digest it before we can discuss these feelings. It’s a bitter way out of the tournament.
“The way we lost makes it harder to understand why we lost. I have to be careful what I say. We have an amazing group and we can definitely do something great again. “
England face Italy in the final on Sunday.