A Young's double slit is illuminated by a single coherent laser beam
PHYSICS · Multi-part · Fermi University Physics · Optics & Photonics · Polarisation and anisotropic media · Interference and diffraction
Optics and Photonics, Ch Two-beam interference and interferometry
Problem
A Young's double slit is illuminated by a single coherent laser beam, but a polariser transmitting only the x (vertical) component is placed over slit 1 and a polariser transmitting only the y (horizontal) component is placed over slit 2, so the two beams reaching the screen have equal irradiance I0 each but are polarised at right angles.
((a)) Predict what is seen on the screen with no further polariser present, and justify it in terms of the two beams' Jones vectors.
((b)) A third polariser (an analyser), oriented at 45∘ to both slit polarisers, is now placed just in front of the screen. Predict whether fringes appear, and if so, state the mean irradiance on the screen relative to I0.