James Roland 
How LEDs Work 

Have you ever wondered how the lights in your alarm clock work? Or have you ever considered how that tiny red light in your TV remote control sends a signal that helps you find your favorite show? What these and countless other bright devices have in common is a light-emitting diode, or LED. But how does an LED work? How is it different from other lightbulbs? Explore the key concepts that make up an LED, including semiconductors, electrons, color, and more. Learn how LEDs are used in electronics, to light homes, and even to grow food for astronauts!