Since a sheet of Polaroid is not an ideal polarizer, not all the energy of the -vibrations...

Since a sheet of Polaroid is not an ideal polarizer, not all the energy of the -vibrations parallel to the TA are transmitted, nor are all -vibrations perpendicular to the TA absorbed. Suppose an energy fraction α is transmitted in the first case and a fraction β is transmitted in the second.

a. Extend Malus’ law by calculating the irradiance transmitted by a pair of such polarizers with angle θ between their TAs. Assume initially unpolarized light of irradiance I0. Show that Malus’ law follows in the ideal case.

---

b. Let α = 0.95 and β = 0.05 for a given sheet of Polaroid. Compare the irradiance with that of an ideal polarizer when unpolarized light is passed through two such sheets having a relative angle between TAs of 0°, 30°, 45°, and 90°.

Figure 1.