Billie Jean LED stairs

Each stair had an infrared emitter on one side sending a “beam” of infrared light across the stair. At the other side, an infrared photo-detector detected the infrared beam. When the beam was broken by someone stepping anywhere on the step, a transistor connected to the detector switched on a set of high power white LEDs to illuminate the entire step. The video only pics up the LED source, however the entire step was light up even with ambient lighting.

Parts Available:, Jameco