Transcript Elliptical polarization

Elliptical polarization
Linear polarization

the two orthogonal components are in phase
Circular polarization

the two orthogonal components have same amplitude and are
+/-90 degrees out of phase.
Elliptical polarization

the two components are not in phase and either do not have
the same amplitude and/or are not 90 degrees out of phase
Wave plate

Optical device : a birefringent crystal with a chosen thickness

Light polarized along the extraordinary/fast axis propagates
faster than the ordinary/slow axis.

Phase shift
Δn : birefringence
L : thickness of the crystal
Wave plate (cont.)


half-wave plate : retards 180
degrees, rotates the
polarization direction of
linear polarized light
quarter-wave plate : retards
90 degrees, changes linearly
polarized light to circular.
Jones calculus

Polarized light is represented by a Jones vector, and linear optical
elements are represented by Jones matrices.
Example:
A half-wave plate:
A HWP
1 0 


0 1
1 0  1  1 
0 1 1   1

   
A quarter-wave plate:
1 0 
AQWP  

 0 i 
1 0  1  1 
0 i  1   i 

   