Why aren't magnifying glasses used in conjunction with solar panels?

[BrownTown]

There is some talk about it, but I think one big reason it isn't done is that the silicon can't handle that much light all at the same time. Its likely as you add more and more light the efficiency drops off because you have saturated the panels ability to produce power. Also the problems of heat and such could be a problem, we all know what happens when you concentrate light on say an ant, and we also know how hte performance of semiconductors is adversely affected by heat, its possible that heating up the panel considerably could also reduce efficiency.