The reason it doesn't burn up is because the dust particles in the air break it up and deplete it. And yeah, he didn't have a lot of light in one spot for a long time.
That is pretty bad ass and would make an awesome flashlight. But I do have 2 questions. 1 how much does one cost, and 2. what would it do to human skin?
These things are dangerous and should only be used in controlled enviroment. Why are these for sale to everybody? You could use it as weapon for god's sake.