Total Internal Reflection
Interactive simulation — adjust parameters and watch the visualization update in real time.
How it works
For n₁ > n₂, there is a critical angle θ_crit = arcsin(n₂/n₁). Rays incident from the denser side at θᵢ > θ_crit undergo total internal reflection instead of refracting out. Optical fibers trap light by TIR at the core–cladding interface.
Key equations
n₁ sin θᵢ = n₂ sin θₜ (Snell)
θ_crit = arcsin(n₂/n₁) when n₁ > n₂