How a 1962 GE Lab Experiment Gave the World Its First Visible LED

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On October 9, 1962, Nick Holonyak Jr., an engineer at General Electric's Syracuse lab, demonstrated the first visible-spectrum light-emitting diode, emitting red light at room temperature. Unlike contemporaries who worked with infrared-emitting diodes, Holonyak used a gallium arsenide phosphide alloy to produce light the human eye could actually see. He boldly predicted that LEDs would eventually replace incandescent bulbs — a claim that seemed far-fetched at the time but has since proven accurate. LEDs operate by converting electrical current directly into photons at a semiconductor junction, making them far more efficient and durable than filament-based bulbs. Today, Holonyak's invention underpins everything from status indicator lights and remote controls to medical sensors, factory cameras, and full-color displays.

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