Polarization

  • Production of linearly polarized light by dichroism : verification of Malus's law with a polarized HeNe laser (or laser diode), polarizer and photodiode.
  • Rectilinear polarization by vitreous reflection at Brewster incidence on a parallel-sided plate (or partial polarization by transmission on a stack of glass plates). Index measurement. Observation of this phenomenon in nature.
  • Rectilinear polarization by light scattering (Rayleigh scattering by a milk suspension in water, "blue sky, sunset"). Observation of this phenomenon in nature.
  • Production of elliptical polarization by metallic reflection or birefringence. Analysis (degree of ellipticity, direction of rotation) using a polarizer and a quarter-wave plate.
  • Qualitative demonstration of the birefringence of a Spath plate (ordinary ray, extraordinary ray, neutral lines). Measure the birefringence of a quartz wedge using the Babinet compensator or by observing a spline spectrum (using miniature spectrometers with interfaced CCDs, or projection on a screen). Determine the angle of a quartz wedge in monochromatic light. Experiment with complementary colors.
  • Quarter-wave, half-wave and wave blades in monochromatic light (HeNe laser or white light + 560 nm filter).
  • Birefringence of scotch tape blades. Relationship between observed color and tape thickness. Measurement of birefringence using the spline spectrum method.
  • Birefringence of a Plexiglas rod. Observe the polarized state of light passing through the rod by scattering. Measure birefringence.
  • Visualization of stresses in a piece of compressed Plexiglas using induced birefringence.
  • Birefringence of liquid crystals placed between two glass slides. Observation of phase transition on heating.
  • Birefringence of liquid crystals: Conduct a quantitative experiment on liquid crystals, illustrating their application todisplays (application of an electric field).
  • Kerr effect: measurement of birefringence as a function of applied field strength. Application to optical modulators.
  • Qualitative demonstration of the rotatory power of a perpendicular quartz slide or a sugar water solution. Measurement of rotatory power as a function of various parameters (length of slide, concentration of solution: Biot's law). Study the abnormal dispersion obtained with Cotton's liquid. For a thick slide: grooved spectrum.
  • Pointing a rectilinear polarization using thepenumbra analyzer or the bi-quartz de Soleil.
  • Faraday effect (Flint bar in the air gap of an electromagnet): measurement of rotatory power as a function of the applied field. Application to optical modulators.
  • The polarizing and phase contrast microscope. Application to the study of crystals and low-contrast transparent objects.
Published on March 13, 2017
Updated on March 13, 2017