Question

Vertically polarized light of intensity I0 is incident on a polarizer with axis oriented vertically, it then goes to an anaylzer with axis oriented horizontally. If a third polarizer is placed between the two with the axis at your choice, what is the maximum intensity that will come through all 3 polarizers?

Please show work andexplain. thank you.

Answer 1

Intensity of light from first polarizer is I_)/2 Let theta is angle between first and second polarizer is I_0/2 cos^2 theta angle between second and third polarizer is 90 - theta intensity of light from third polarizer is I = I_0/2 cos^3 theta cos^2 (90 - theta) I = I_0/2 cos^2 theta sin^2 theta I = I_0/8 (2 cos theta sin theta)^2 I = I_0/8 (sin 2 theta)^2 for maximum intensity sin 2 Theta = 1 I_max = I_0/8