The term of art there is "concentrated PV solar". Big fresnel lenses concentrating light onto a postage stamp of photovoltaic material. Requires sun tracking to keep the light on the PV, so it's useless for rooftop solar.
If you look it up you'll notice all the citations are decades old. Designed for a world where PV was terribly expensive, so you'd trade a lot of mechanical and packaging complexity to use as little of it as possible.
Then silicon got 100x cheaper. Now every solar install uses fixed-angle racks or just plopping the panels flat on the ground. You lose some efficiency, but land is cheap, so who cares?
