The lense, though, not the interior-colored plastic bezel.
If you look real closely in the little crack between the lense and the bezel, you can see the two (per side, front and back, 4 total) little tabs that will disengage to let the lense pop out. They're closer together on one side than the other, but I can't recall which. Either way, if you pry first about 1/4 of the way in from an end, and then 1/4 of the way in from the other end, you're sure to get it done.