Edexcel A Level Physics:复习笔记5.15 Total Internal Reflection

• Total internal reflection (TIR) occurs when:

The angle of incidence is greater than the critical angle and the incident refractive index n1 is greater than the refractive index of the material at the boundary n2

• Therefore, the two conditions for total internal reflection are:
  • The angle of incidence, θ1 > the critical angle, C
  • Refractive index n1 > refractive index n2 (air)

Diagram showing refraction, the critical angle and total internal reflection

• Two conditions are necessary for total internal reflection to occur:
  • The light must be going from a more dense medium into a less dense one
  • The angle of incidence must be greater than the critical angle