PHYSICS · Multi-part · Fermi University Physics · Optics & Photonics · Interference and diffraction · Interference and diffraction
Optics and Photonics, Ch Multiple-beam interference: thin films, multilayers and the Fabry-Perot etalon
Problem
A camera lens is made of crown glass with ns=1.52. It is to be coated with a single quarter-wave antireflection layer for sodium light, λ=589 nm, at normal incidence in air (n0=1.00).
((a)) Find the ideal (zero-reflectance) coating index nf.
((b)) The nearest durable coating material is magnesium fluoride, nf=1.38. Find the thickness of a quarter-wave layer of this material at 589 nm.