Optics > Polarization > Polarization by Double Refraction
DCS# 6H35.51
QUARTZ WEDGE
APPARATUS
quartz wedge
105-23-E6
two polarizers
105-23-E6
overhead projector
105
DESCRIPTION
Place quartz wedge between crossed polarizers
on the overhead projector. The color of the light that makes it through
the analyzer varies with the thickness of the quartz.
NOTES
Quartz is birefringent and so perpendicular
components of linearly polarized light travel at different speeds through
the material, emerging with a phase difference that depends on the thickness
of the material and the wavelength of the light (since n is wavelength-dependent).
In general the light emerges elliptically polarized.
