%!
(lenses.inc) run


48 24 scale
1 48 div  setlinewidth
4 3 translate
90 rotate
%show axis
gsave
2 2 translate
-3.5 0 moveto
6 0 lineto
stroke
newpath
0 -3 moveto
0 3 lineto
stroke
grestore

newpath
0.8 0.8 1 setrgbcolor
2 2 1 0 360 arc
fill
0 0 0 setrgbcolor
2 2 1 0 360 arc

stroke


gsave
newpath
0.8 0.8 1 setrgbcolor
11.5 2 1.5 290 70 arc 
fill
0 0 0 setrgbcolor
11.5 2 1.5 290 70 arc 
stroke
grestore

gsave
newpath
0.8 0.8 1 setrgbcolor
12.5 2 1.5 110 250 arc 
fill
0 0 0 setrgbcolor
12.5 2 1.5 110 250 arc 
stroke
grestore


gsave
newpath
0.8 0.8 1 setrgbcolor
17 2 1.5 290 70 arc 
fill
0 0 0 setrgbcolor
17 2 1.5 290 70 arc 
stroke
grestore

gsave
newpath
0.8 0.8 1 setrgbcolor
18 2 1.5 110 250 arc 
fill
0 0 0 setrgbcolor
18 2 1.5 110 250 arc 
stroke
grestore


% red ray
gsave
1 0 0 setrgbcolor
/x 2.9 def
/Po [0 x] def
/Vo [1 0] def 
/P1 Po Vo [2 2] 1 hit def 
0 x moveto
P1 0 get P1 1 get lineto

/n [2 2] P1 gradient normalized def
/v1 n [1 0] 1.05 refraction def
/P2 P1 v1 [2 2] 1 hit def
P2 0 get P2 1 get lineto

/v2 [1 0] v1 .45 refraction def
/p3 P2 v2 [1 0 -12] line-intersection def
p3 0 get p3 1 get lineto

/v3 [1 0] v2 -.6 refraction def
/p4 p3 v3 [1 0 -17.5] line-intersection def
p4 0 get p4 1 get lineto

/v4 [1 0] v2 1 refraction def
/p5 p4 v4 [1 0 -24] line-intersection def
p5 0 get p5 1 get lineto

stroke
grestore

gsave
1 0 0 setrgbcolor
/x 1.1 def
/Po [0 x] def
/Vo [1 0] def 
/P1 Po Vo [2 2] 1 hit def 
0 x moveto
P1 0 get P1 1 get lineto

/n [2 2] P1 gradient normalized def
/v1 n [1 0] 1.05 refraction def
/P2 P1 v1 [2 2] 1 hit def
P2 0 get P2 1 get lineto

/v2 [1 0] v1 .45 refraction def
/p3 P2 v2 [1 0 -12] line-intersection def
p3 0 get p3 1 get lineto

/v3 [1 0] v2 -.6 refraction def
/p4 p3 v3 [1 0 -17.5] line-intersection def
p4 0 get p4 1 get lineto

/v4 [1 0] v2 1 refraction def
/p5 p4 v4 [1 0 -24] line-intersection def
p5 0 get p5 1 get lineto

stroke
grestore