Wave Optics

Description:

Observe diffraction around a straight edge, opaque disk, single slit, double slit, and diffraction grating. Calculate slit width and laser wavelength.

Equipment:

  • Optical bench, Q6
  • Single slit wheel, Q2
  • Double slit wheel, Q2
  • 100 mm lens, Q2
  • Slide holder, R2
  • Diode laser, R4
  • Diffraction grating, B3
  • Opaque point / edge slide, B3
  • Ruler, I4
  • Meter stick, I4

Setup Procedure:

Place optical components on the optical bench as in the picture.

Concept:

When light bends around a straight edge, secondary wavelets emerge as circular waves. When light bends around an opaque disk, a bright spot is observed in the center of the diffraction pattern due to superposition. Locations of minimas and maximas can be calculated using geometry.