Each week, we spotlight a cool innovation recommended by some of the industry's top tech writers. This week's pick is a flexible membrane laser that can attach to contact lenses.

Superman's laser vision just moved a step closer to reality, said Neil Savage at IEEE Spectrum. Researchers at the University of St. Andrews in Scotland have developed an ultra-thin, laser-emitting membrane, made from an organic semiconducting polymer, that can be attached to contact lenses. The team tested the membranes and contacts on cow eyeballs, but don't worry: They aren't planning to build an army of bovines "with laser-beam eyes."

Instead, the lasers would produce a unique digital bar code when illuminated with another laser, allowing it to serve as a kind of identification for the contact lens wearer, possibly adding a second layer of authentication to an iris scan. The same could be done for fingerprint scans; the team has attached a membrane to a person's thumbnail. And several such lasers could be affixed to a banknote, giving it a unique "spectral" signature to guard against counterfeiting.