What is the divergence angle in relation to laser beams?

The divergence angle of a laser beam is indeed related to the rate at which the beam's diameter expands as it travels through space. This concept is crucial in understanding how laser beams behave over distance; even though lasers are designed to emit a highly collimated beam, some spreading occurs as the beam propagates. The divergence angle is a measure of how quickly this spreading occurs, typically expressed in milliradians.

A smaller divergence angle indicates a more focused beam that maintains its intensity over greater distances, while a larger angle signifies that the beam will spread out more rapidly, reducing intensity more quickly. Understanding the divergence of laser beams is important for applications in laser safety, optics, and various technological fields, where the beam’s performance and safety implications can depend significantly on this angle.