Source
%% PhS
%%

50 setxunit
0 10  setxrange
-3.5 3.5 setyrange

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% definition des points
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

/H1 {0 0} def
/H2 {9 0} def
/V1 {2 -3.5} def
/V2 {2 3.5} def
/K {2 0} def
/F {5 0} def
/D {1.8 -3} def
/p {2} def
/e {0.7} def

/rhox {settvar t cos e mul neg 1 add 1 exch div p mul t cos mul} def
/rhoy {settvar t cos e mul neg 1 add 1 exch div p mul t sin mul} def

/Mx {60 rhox 5 add} def
/My {60 rhoy} def
/M {Mx My} def
M point

/H {M V1 V2 orthoproj} def
H point

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% definition d'une couleur
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

/coul1 {120 255 div 70 255 div 9 255 div setrgbcolor} def

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% tracés
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1.3 setlinewidth
continu
[K F] points
[H1 H2] ligne
[V1 V2] ligne
[M F] ligne
[M H] ligne

coul1
40 320 settrange

rouge
[F 6 0] ( ->) ligne
[F 5 1] ( ->) ligne
H2 F M 1.5 (->) tripointarc

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% texte
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

setTimesItalic
noir
(K) K [1.5 dup] dltext
(M) M [1.5 dup] uctext
rouge
(F) F [1.5 dup] dtext
bleu
(H) H [1.5 dup] cltext

noir
<latex>
$\mathcal{D}$
</latex>
D [1.5 dup] cctexlabel

<latex>
$\Delta$
</latex>
8.5 0 [1.5 dup] dctexlabel

rouge
<latex>
$\theta$
</latex>
6.6 0.7 [1.5 dup] uctexlabel

<latex>
$\vec{\imath}$
</latex>
5.8 -0.2 [1.5 dup] cctexlabel

<latex>
$\vec{\jmath}$
</latex>
4.8 0.7 [1.5 dup] cctexlabel