A
single slit, as shown on the right, also causes a
diffraction pattern. This results because the slit is of
finite width, and every point in the slit serves as a
source of a wave. Consider a slit of width a/2.
For light that travels in the direction q, the contribution from point
will cancel the contribution from the point 1
if the difference 2D is a
half-integral number of wavelengths. Thus, there is a xMINIMUM
for angles,For the first
maximum
for the two-slit problem, only that one is
refering to the slit width here,
whereas we refered to the slit separation a
in the two-slit problem.d |