Coherent Source

Definition

A coherent source refers to a source that emits waves with a constant phase relationship. In other words, the crests and troughs of the waves are aligned and maintain their positions over time.

Analogy

Think of a synchronized swimming team performing perfectly choreographed routines. Each swimmer moves in harmony with others, maintaining precise positions and timing. Similarly, waves from a coherent source move together in perfect alignment.

Related terms

Interference: The phenomenon that occurs when two or more waves overlap and combine either constructively (amplitude increases) or destructively (amplitude decreases).

Diffraction Grating: A device consisting of many closely spaced slits or grooves that can separate incoming light into its component wavelengths.

Huygens' Principle: A principle stating that every point on a wavefront acts as a source of secondary spherical wavelets that spread out in all directions.