Simple ballpoint pen can write custom LEDs

Researchers working with Chuan Wang, an associate professor of electrical and systems engineering at the McKelvey School of Engineering at Washington University in St. Louis, have developed ink pens that allow individuals to handwrite flexible, stretchable optoelectronic devices on everyday materials including paper, textiles, rubber, plastics and 3D objects.

LED Material Shines Under Strain

A team led by researchers at Lawrence Berkeley National Laboratory (Berkeley Lab) and UC Berkeley has demonstrated an approach for achieving LEDs with near 100% light-emission efficiency at all brightness levels.