Imagine a runner who doesn't need to carry a stopwatch or cell phone to check her time: She could just gaze at the glowing stopwatch display on the back of her hand. Such human-machine interfaces are ...

In what may be either the most discreet or the most conspicuous of wearable electronics, a team of researchers led by Desheng Kong of Nanjing University has developed a prototype stretchable stopwatch ...

The exposure tester in thisDesign Idea measures the on timeof a light source, whether an LED, anincandescent lamp, a halogen lamp, oranother source. It can be made with anordinary stopwatch and a few ...