Key Stage 5
Meaning
Two sources of waves are coherent if they emit waves with a constant phase difference.
About Coherence
- Coherent sources produce waves that are in sync, having a constant phase relationship.
- Necessary for producing clear interference patterns.
- Coherent waves are typically monochromatic and have the same frequency.
- Essential in applications like lasers, holography, and interferometry.
- Coherence can be temporal (constant phase difference over time) or spatial (constant phase difference
across space).
- The degree of coherence affects the visibility and contrast of interference fringes.
- Achieving coherence often involves stabilizing the frequency and phase of the wave sources.
Examples
Laser light is coherent and can produce clear interference and diffraction patterns.
In a double-slit experiment, coherent light sources create distinct and stable interference fringes.