Question

(a) Compute the far-field (Fraunhofer) diffraction pattern on a screen at location z due to a rectangular
aperture of width b at z = 0. Assume the aperture is uniformly illuminated by a plane wave at normal
incidence to the aperture. You may restrict your calculation to one dimension.
(b) Write down the far-field diffraction pattern if the aperture is instead a pair of narrow slits separated
by a distance a.
(c) Use the convolution theorem to write down the far-field diffraction of an aperture consisting of two
parallel slits of width b with centers separated by distance a.

As long as diffraction is a Fourier transform, make use of the convolution theorem
to get composite patterns.

Answer 1