Question

A quartz plate cut parallel to the optical axis is placed between two crossed Nicol prisms. The angle between the principal directions of the Nicol prisms and the plate is equal to 45°. The thickness of the plate is d = 0.50 mm. At what wavelengths in the interval from 0.50 to 0.60 μm is the intensity of light which passed through that system independent of rotation of the rear prism? The difference of refractive indices for ordinary and extraordinary rays in that wavelength interval is assumed to be Δn = 0.0090.

Answer 1

As in the previous problem the quartz plate introduces a phase difference δ between the O & E components. When δ = π/2 (modulo π) the resultant wave is circularly polarized. In this case intensity is independent of the rotation of the rear prism. Now

These are the values of λ which lie between 0.50μm and 0.60μm .