Total internal reflection
What Total internal reflection means in Physics A-Level, as defined for AQA, OCR.
Definitions of Total internal reflection
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Reference: OCR
Occurs when light travels towards a less optically dense medium and the angle of incidence exceeds C, so no light refracts out and all the light is reflected internally.
Occurs at the core–cladding boundary when light meets it at an angle of incidence greater than the critical angle, so light is repeatedly reflected along the core.
Occurs when light travels from a medium of higher refractive index to one of lower refractive index and the angle of incidence exceeds the critical angle.
Topics that use Total internal reflection
- Fibre optics and endoscopy (A-level only) (AQA A-Level)
- Refraction at a plane surface (AQA A-Level)
- Electromagnetic waves (OCR A-Level)
Related terms
- Critical angle
- Absorption
- Acceptance angle
- Coherent fibre bundle
- Internal imaging
- Material dispersion
- Medical imaging and endoscopy
- Modal dispersion
Using Total internal reflection in the exam
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