72 



AN ELEMENTARY THEORY OF PHASE MICROSCOPY 



B 



Fig. n.22. The effect of the choice of widtfi of the :unml;ir conjugate area of a 

 0.35A±x/-i diffraction plate upon the primary diffraction image. The location of 

 the first minimum is displaced towards larger values of r/tn as the width of the con- 

 jugate area is reduced, h'^ = 0.35 in A and B. 



