[" The box of a pin hole camera,of length "L," has a "],[" hole of radius a.It is assumed that when the hole "],[" is illuminated by a parallel beam of light of "],[" wavelength "lambda" the spread of the spot (obtained on "],[" the opposite wall of the camera) is the sum of its "],[" geometrical spread and the spread due to "],[" diffraction.The spot would then have its minimum "],[" size (say b "b_(min)" ) when "quad " [JEE (Main)-2016] "]