PHY2061 R. D. Field Department of Physics chp42_1.doc University of Florida Narrow Slit Diffraction Consider a plane wave with wavelength λincident on a narrow slit of width W. Case 1(λ<< W) corresponds to little or no diffraction with a bright spot on the screen of width not much larger than W. Case 2(W << λ) corresponds to a lot of diffraction resulting in the spreading out of the light across the screen in the form of a &diffraction pattern± with a central bright spot and a series of dark and light fringes similar to the two-slit interference pattern. Actually diffraction is a form of interference in which each of the infinite number of points along the wavefront acts as a point source of secondary spherical wavelets (Huygen&s Principle). Each of these waves has a different path length to the
This is the end of the preview. Sign up
access the rest of the document.
This note was uploaded on 05/31/2011 for the course PHY 2061 taught by Professor Fry during the Spring '08 term at University of Florida.