d = 5;
h = 3.6;
l = 22;
R = 50;
n = 2.44;
λ = 2.4 × 10-3 ;
MS =  1 d . 1 h / n .
0 1
0
1
AS [F_] = Part[MS , 1, 1];
BS [F_] = Part[MS , 1, 2];
CS [F_] = Part[MS , 2, 1];
DS [F_] = Part[MS , 2, 2];
1
-1
F
0
. 1 l .
1
0 1
1
-2
R
0
. 1 l .
1
0 1
1
-1
F
0
. 1 h / n . 1 d ;
1
0
1
0 1
2
лаба радиус пучка.nb
λ
W[F_] =
Norm[BS [F]]
π
1
;
2
-  AS [F]+DS [F] 
2
Plot[W[F], {F, 30, 1000}, PlotRange → Full]
1+
w[z_, F_] = W[F]
2
λz
π (W[F])2
;
Plot[{w[z, 10 000], w[z, 100], w[z, 500], w[z, 30]},
{z, 400, 700}, PlotRange → Full, PlotLegends → Automatic]
0.142
0.140
0.138
0.136
0.134
0.132
400
600
800
1000
4.0
3.5
1
2
3.0
3
4
2.5
450
500
550
600
650
700