# Quiz 2 - reduce the reflection of normally incident light...

This preview shows page 1. Sign up to view the full content.

Quiz 2 May 5, 2008 1. (a) What is Brewster’s angle? (b) Calculate the Brewster angle for a plate of crown glass (n=1.52) in air. (Hint: use 2 1 1 2 2 1 1 2 // cos cos cos cos θθ θ n n n n r + = and Snell’s law). 2. (a) What is evanescent wave? (2) Prove that evanescent wave can be expressed as () y t n x k i E E t t t t α ω = exp sin exp 0 Hint: 3. (a) Describe the principle of anti-reflection coating to reduce the reflection from the air-glass interface. (b) At normal incident angle, show that the refractive index of the idea material for anti-reflection coating is glass n . (c) A glass microscope lens having an index of 1.55 is to be coated with a film to increase the transmission (or
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: reduce the reflection) of normally incident light at 550nm. What minimum thickness should be deposited on the lens? (Hint: 2 1 2 1 2 2 ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ + − = n n n n r at θ =0 ° ; phase difference between two light waves is the product of propagation number (k) and path difference.) 4. Explain the phenomenon of Newton’s ring and give two examples of practical applications of Newton’s rings. )] ( exp[ t r k i E E t t ot t − ⋅ = G G G G ) cos sin ( z t x t t t n n k k G G G − − =...
View Full Document

{[ snackBarMessage ]}

Ask a homework question - tutors are online