Rami Arieli: "The Laser Adventure"

Rami Arieli: "The Laser Adventure" Chapter 7 Section 5, page 20

Graph of Malus Law

Figure 7.33 describes I/I₀ as a function of the angle a.

Figure 7.33: Malus Law, I/I₀ as a function of the angle a.

Question:

What is the intensity of unpolarized light after passing through 3 polarizers. Each of the polarizers is placed at different angle to the previous polarizer?

Solution:

The angle between the first and the second polarizers is a, and the angle between the second and the third polarizers is b. Applying Malus law twice:

I = I₀*cos²a*cos²b