光電工程概論
Homework 3
96 年度第一學期
碩研光電ㄧ甲
1. Draw the wavefront of the following uniform plane waves:
(a)  ( x, t )  cos(x  t )

(b)  (r , t )  cos(x  y  t )
.
2.
(P4.25*) A coin is resting on the bottom of a tank of water (nw=1.33) 1.0m deep.
On top of the water floats a layer of benzene (nb=1.50), which is 20.0cm thick.
Looking down nearly perpendicularly, how far beneath the topmost surface does
the coin appear? Draw a ray diagram.
3.
A light bulb puts out 20W of radiant energy (most of it IR). Assume it to be a
point source and calculate the irradiance of 1.00m away.
4.
Suppose a lightwave that is linearly polarized in the plane-of-incidence impinges
at 30 on a crown-glass (ng = 1.52) plate in air. Compute the appropriate
amplitude reflection and transmission coefficients at the interface.
30
ni = 1
ng = 1.52
5. (P4.58) A glass block having an index of 1.55 is covered with a layer
of water of index 1.33. For light traveling in the glass, what is the
critical angle at the interface ?