This 3-D printer can fit in the palm of your hand

In a few years, you might be able to 3-D print right in the palm of your hand.

A new 3-D printer that’s mere millimeters in size could offer a new way to produce customizable objects, scientists report June 6 in Light: Science & Applications. Rather than relying on a symphony of moving parts — like a bulky tabletop 3-D printer — the device uses antennas on a tiny chip to guide a light beam into a well of specialized resin above the chip. When exposed to the visible light, the resin cures into hard, customizable shapes in just seconds.

“This system is completely rethinking what a 3-D printer is,” says study coauthor Jelena Notaros, an electrical engineer at MIT. “It is no longer a big box sitting on a bench in a lab creating objects, but something that is handheld and portable.”

The proof-of-concept device, which combines silicon photonics and photochemistry, has so far printed flat objects, including the MIT logo. Eventually, researchers hope the printer can produce bike parts, medical device components and other objects useful for daily life.

Miniaturizing 3-D printing has other interesting potential applications, from printing in space to inside the human body, says engineer Sourabh Saha of Georgia Tech in Atlanta. But the road ahead is long. For instance, the researchers may encounter challenges in using light beams to print independent resin layers. “It’s not quite there,” Saha says. “It’s very early-stage work.”