If instead of one point source, suppose point sources are uniformly spaced and also arranged along a line segment of total length that is parallel to the -axis, as shown below.
Calculate the irradiance at the screen for the aperture of Exercise 1 if one source is on the symmetry axis, cm, and: (a) ; (b) ; (c) and . How many distinct shadow regions (areas characterized by different irradiance) appear in each case?