As I began research on an invention that has, needless to say, revolutionized traffic safety, I wondered how often any of us thinks about how common, everyday items came into our lives. On my desk right now I have a paper weight, a coffee cup, a notepad, an ink pen, and facial tis...
his colleagues thought he was unrealistic. Today, his discovery of light-emitting diodes,or LEDs, is used in everything from DVDs to alarm clocks to airports. Dozens of his students have continued his work, developing lighting used in traffic lights and other everyday ...