Nth Degree chief scientist William J. Ray doesn’t think compact fluorescent light bulbs are any kind of solution for cheap efficient lighting. “Do you know what’s in those things?” he asked me when I stopped by his booth at the ARPA-E Energy Innovation Summit last night. “Methyl mercury.” Poison, in other words.

He says he and his team at Tempe-based Nth Degree Technologies think they have a better idea: printable inorganic LEDs. Each one is a mere 24-microns across, about the size of a white blood cell, but can emit enough light to read by. No special manufacturing process required; just print them out in any desired pattern using conventional printing techniques.

Watch Ray demo a sheet of prototypes and hear his explanation in my video above.