EM Waves - Lecture 11 [Total Transmission & Total Reflection] -- (25-26)

Welcome to Lecture 11 of the Electromagnetic Waves course (2025/2026). In this lecture, we examine two critical phenomena occurring at dielectric interfaces under oblique incidence: total transmission via Brewster's angle and total internal reflection via the critical angle, deriving their mathematical formulations and exploring their key practical applications. Key Topics Covered: • Total Transmission & Brewster's Angle (Polarization Angle, θ_B): Condition for zero reflection (Γ_TM = 0) under parallel (TM) polarization Mathematical derivation: tan(θ_B) = sqrt(ε2 / ε1) for non-magnetic media Why Brewster's angle does not exist for TE polarization in non-magnetic materials Practical applications: Optical polarizing windows, Brewster windows in gas lasers, and glare reduction • Total Internal Reflection (TIR) & Critical Angle (θ_c): Practical applications: Dielectric waveguides, optical fibers, and prism couplers