2500*10^-9; k = 2*Pi/lambda; d = 0.1*10^-3; path1[x_, y_] := Sqrt[y^2 + (x + d/2)^2]; path2[x_, y_] := Sqrt[y^2 + (x - d/2)^2]; phasediff[x_, y_] := (2*Pi/lambda...
