Pen with silver ink draws circuits on the fly

Their pen dispenses a silver solution that allows the user to draw functioning electrical circuits on a wide variety of surfaces. Here a flexible array of LEDs was mounted on paper, and then interconnected by hand-drawn silver ink lines.

"Pen-based printing allows one to construct electronic devices 'on-the-fly', using very low cost, ubiquitous printing tools," said Jennifer Lewis, one of the lead researchers and director of the Frederick Seitz Materials Research Laboratory at the University of Illinois.