Page 662 - Introduction to Information Optics

11. Information Display with Optics

Polarization axis

Polarizer Polarizer
Fig. 11.22. Electro-optic intensity modulator.

and

0 0
(11.39)
0 1

respectively. The two polarizers, aligned in such a way that their polarization
axes are 90° with respect to each other, as shown in Fig. 11.22, are called
crossed polarizers.
The light that passes through the polarizer can be described by the product
of the Jones vector and the Jones matrix of the polarizer, while the rotation of
a coordinate system can be described by a rotation matrix. The rotation matrix
is given by

cos 6 sin 8
M rot(t?) = (11.40)
— sin $ cosf?/'

where 0 represents an anticlockwise rotation of the original axes so as to form
a new coordinate system. It can be shown that the Jones matrix of a polarizer
with a polarization axis making an angle a with the x-axis is

sin a cos a
(11.41)

The state of the output light through an optical system can be calculated by