A manufacturer wishes to fabricate a single-layer antireflection coating for a glass window (nglass=1.50) that will suppress reflected orange light of wavelength λ0=600nm in air when the light arrives at 40∘ to the normal in air. The coating material has index nc=1.30 and is surrounded by air.
(a) Derive an expression for the optical path difference between the two reflected rays in terms of the coating thickness t, the index nc, and the angle the light makes inside the coating.
(b) Using the indices involved, determine whether each of the first two reflections introduces a 180∘ phase shift. State the net additional half-wave (if any) that must be taken into account.
(c) Calculate the smallest coating thickness that will suppress the reflection of the orange light at the specified angle.
(a) Derive the optical path-difference expression for the two reflected rays.
(b) Determine the phase shifts at the two reflections and state the net half-wave factor.
(c) Calculate the least physical thickness that eliminates reflection of λ0=600nm light at 40∘ incidence.