Metalenses are a relatively fringe optical technology — at least, they were. Until now, it has been largely pursued by startups and scientists but that is changing as Canon has jumped into the fray and not only makes them but also produces the equipment necessary to manufacture them.
So basically nano-scale Fresnel lenses?
Those are beautiful. A couple years ago I went on a hunt trying to find one to hang up as wall art. They are pricey.