Modal dispersion
What Modal dispersion means in Physics A-Level, as defined for AQA.
Definitions of Modal dispersion
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Reference: AQA
Arises because rays taking different paths through a step-index core have different path lengths, so they arrive at different times even at the same wavelength.
Arises because rays travelling different paths in a multimode fibre have different path lengths and therefore different transit times.
Topics that use Modal dispersion
- Refraction at a plane surface (AQA A-Level)
Related terms
- Absorption
- Acceptance angle
- Critical angle
- Material dispersion
- Pulse broadening
- Step-index optical fibre
- Total internal reflection
Using Modal dispersion in the exam
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