412 Diffraction Patterns and Polarization*P38.7The rectangular patch on the wall is wider than it is tall. The aperture will be taller than it is wide.For horizontal spreading we havetan...sin..θθλwidthwidthwidthwidthwidthm 2mm0.012 2m=====×=×−−yLaa0 1104 50 012 21632 8105 181095For vertical spreading, similarlytan...sin..θλθheightheightm 2mm0.000 667m====×=×−−0 0064 50 000 6671632 8109 491094ahP38.8Equation 38.1 states thatsinθλ=ma, where m= ±±±123,,,…. Therequirement for m=1 is from an analysis of the extra path distancetraveled by ray 1 compared to ray 3 in Figure 38.5. This extradistance must be equal to λ2for destructive interference. When thesource rays approach the slit at an angle β, there is a distance addedto the path difference (of ray 1 compared to ray 3) of
This is the end of the preview.
access the rest of the document.