PHYS 117 Chapter Notes - Chapter 24: Fraunhofer Diffraction, Diffraction Grating, Diffraction
Document Summary
Conditions for interference: the sources are coherent, which means that the waves they emit must maintain a constant phase with respect to one another, the waves have identical wavelengths. Ordinary light sources are said to be incoherent. The path difference determines whether the two waves are in phase when they arrive at p. Secondary maxima: a series of narrower, less intense secondary bands. Diffraction: the spreading out of light from its initial line of travel. Occurs when waves pass through small openings, around obstacles, or by sharp edges. Fraunhofer diffraction: occurs when the rays leave the diffracting object in parallel directions. A bright fringe is observed along the axis at =0, with alternating dark and bright fringes on each side of the central bright fringe. According to huygens" principle, each portion of the slit acts as a source of waves.
