510 



BELL SYSTEM TECHNICAL JOURNAL 



> 



-0.1 



-^ -2.0 -1.8 -1.6 -1.4 -1.2 -1.0 -0.8 -0.6 -0.4 -0.2 0.2 0.4 0.6 



IL'_ Jl_o 

 N -N "^ 



0.4 



-1.0 -0.8 -0.6 -0.4 -0.2 



0-2 0.4 -0.6 0.8 1.0 I. 



n'_n. i 



isr"N'^ 



I.O 



0.9 



0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 



Fig. 24 — Circular aperture with 25 per cent overlap. 



