%!
(lenses.inc) run

48 dup scale
0.01 setlinewidth
2 2.5 translate
0 0 0 setrgbcolor

%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

newpath
0.8 0.8 1 setrgbcolor
2 2 1.5 310 50 arc
3.7 3 lineto
3.7 1 lineto 
closepath
fill

gsave
0 setgray
2 2 1.5 310 50 arc
3.7 3 lineto
3.7 1 lineto 
closepath
stroke

% 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 0.326 refraction def
/p3 P2 v2 [2 2] 1.5 hit def
p3 0 get p3 1 get lineto

/v3 [1 0] v2 0.5 refraction def
/p4 p3 v3 [1 0 -3.7] line-intersection def
p4 0 get p4 1 get lineto

/v4 [1 0] v3 1.5 refraction def
/p5 p4 v4 [1 0 -16 3 div] line-intersection def
p5 0 get p5 1 get lineto
stroke
grestore

% Red Ray bottom
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 0.326 refraction def
/p3 P2 v2 [2 2] 1.5 hit def
p3 0 get p3 1 get lineto

/v3 [1 0] v2 0.5 refraction def
/p4 p3 v3 [1 0 -3.7] line-intersection def
p4 0 get p4 1 get lineto

/v4 [1 0] v3 1.5 refraction def
/p5 p4 v4 [1 0 -16 3 div] line-intersection def
p5 0 get p5 1 get lineto
stroke

grestore



% blue ray
gsave
0 0 1 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 0.215 refraction def
/p3 P2 v2 [2 2] 1.5 hit def
p3 0 get p3 1 get lineto

/v3 [1 0] v2 0.8 refraction def
/p4 p3 v3 [1 0 -3.7] line-intersection def
p4 0 get p4 1 get lineto

/v4 [1 0] v3 1.9 refraction def
/p5 p4 v4 [1 0 -16 3 div] line-intersection def
p5 0 get p5 1 get lineto
stroke
grestore

% blue ray bottom
gsave
0 0 1 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 0.215 refraction def
/p3 P2 v2 [2 2] 1.5 hit def
p3 0 get p3 1 get lineto

/v3 [1 0] v2 0.8 refraction def
/p4 p3 v3 [1 0 -3.7] line-intersection def
p4 0 get p4 1 get lineto

/v4 [1 0] v3 1.9 refraction def
/p5 p4 v4 [1 0 -16 3 div] line-intersection def
p5 0 get p5 1 get lineto
stroke
grestore

gsave
/Helvetica-Bold findfont
.3 scalefont
setfont
0 4 moveto
(Correction chormatic aberration ) show
grestore

gsave
/Helvetica findfont
.25 scalefont
setfont
0.5 2.2 moveto
(lens ) show
grestore