Question 1 A thin film of polystyrene is used as an antirefl

Question 1 A thin film of polystyrene is used as an antireflective coating for fabulite (known as the substrate). The index of refraction of the polystyrene is 1.49, and the index of refraction of the fabulite is 2.409. (Figure 1) Figure 1 1of1 Light rays Polystyrene n:1.49 Fabulite 2.409

Solution

the minimum thickness is calculated as follows:

     t = wavelength/4n = 500x10^-9 / 4*1.49 = 83.89 nm = 83.9 nm