Could it be used to test if drugs are the genuine stuff?
I mean, really simple stuff for anyone to get hurt with chemically, things like this can help with. Maybe not the full functionality like we see on star trek. But, I'm sure people with allergies, ravers with molly, moms that want to know what is safe for their babies, etc can all have something that can help mitigate risk in some small way.
At best, this is an ersatz replacement for the tunable filter on a hyperspectral imaging system. There are some advantages (off hand, acquisition rate is a big one) to a more diverse mosaic filter, but other than in using QDs as the actual filter medium, this idea is not at all new.