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Physics

Laser Operation Principles

Quick fact

The first working laser, built by Theodore Maiman in 1960, used a ruby crystal and produced pulses of red light; today lasers can create beams powerful enough to cut steel or gentle enough for eye surgery.

Why this is interesting

You shine a flashlight and get a diffuse, spread-out beam. But a laser pointer shoots a pencil-thin ray that can travel miles. What makes laser light so different?