Task id15510

The figure shows the wave fronts at normal incidence of the beam (i = 0) on a birefringent crystal at different directions of the main axis 1 of the crystal. Give a qualitative description of what will happen to rays o and e if a light ray falls on the crystal at an angle i = / = 0. Assume that in any of the cases under consideration the incident ray remains in the plane of the drawing.