Educational Objectives

  • He-Ne Laser
  • Contrast Function
  • Coherence Length
  • Two Beam Interference
  • Homodyne Interferometer
  • Fringe Detection, Counting and Interpolation
  • Definition of Length

The basic version of a Michelson interferometer is used to teach the handling, alignment, and measurement of a homodyne interferometer system. By interfering two laser beams, fundamental properties of Gaussian beams as well as wave fronts and interference patterns are demonstrated and investigated. With one interferometer mirror on a mechanical rack and pinion drive the beam path difference can be varied and hence the interferometer contrast function can be probed. The measurement of coherence length of the He-Ne laser introduces the student to the spectral emission bandwidth of the laser source.

Order No. 4900-9-1300