\documentclass{standalone} \usepackage{xcolor} \definecolor{darkgreen}{HTML}{329D32} \usepackage{tikz} \begin{document} \begin{tikzpicture}[scale=2.5] \draw[color=blue](0,0)ellipse(1.5 and 1.0); % angle of L \def\tt{15} % foci ae=sqrt(1-b^2/a^2) \def\ae{1.118} % collision point \def\Px{0.5} % Py=sqrt(1-Px^2/a^2) \def\Py{0.943} % slope Px/(a^2*sqrt(1-Px^2/a^2)) \def\slope{0.236} % phi: atan(\Py/(\ae+\Px)) \def\ph{15.2} % phi': pi-atan(\Py/(\ae-\Px)) \def\php{108.2} % lambda: pi-atan(\slope) \def\lam{151.7} % psi: pi+phi-lambda \def\ps{43.5} % h=sin(\ph)*sqrt((\Px+\ae)^2+Py^2) \def\h{0.491} % foci \path(-\ae,0)coordinate(F1); \path(\ae,0)coordinate(F2); % collision point \path(\Px,\Py)coordinate(P); %Q \path(F1)++(90+\tt:\h)coordinate(Q); \draw[densely dotted](F1)++(\tt:3)--++(180+\tt:3.5); \draw[densely dotted](F2)++(\tt:0.7)--++(180+\tt:3.5); \draw[line width=1](P)++(\tt:1)--++(180+\tt:3.5); \draw[color=gray](F1)--(P)--(F2); \draw[color=darkgreen,dashed](P)--++(1,-\slope); \draw[color=darkgreen,dashed](P)--++(-1,\slope); \draw[rotate=\tt](F1)++(0.4,0)arc(0:\ph:0.4); \draw(F1)++(\tt+\ph/2:0.5)node{$\varphi$}; \draw[rotate=\tt](F2)++(0.15,0)arc(0:\php:0.15); \draw(F2)++(\tt+\php/2:0.25)node{$\varphi'$}; \draw[rotate=\tt](P)++(0.1,0)arc(0:\lam:0.1); \draw(P)++(\tt+\lam/2:0.2)node{$\lambda$}; \draw[rotate=\tt+\lam](P)++(0.2,0)arc(0:\ps:0.2); \draw(P)++(\tt+\lam+\ps/2-7:0.3)node{$\psi$}; \draw[rotate=180+\tt+\lam](P)++(0.2,0)arc(0:-\ps:0.2); \draw(P)++(\tt+180+\lam-\ps/2:0.3)node{$\psi$}; \fill[color=red](F1)circle(0.03); \draw(F1)++(0,-0.15)node{$O$}; \fill(F2)circle(0.03); \draw(F2)++(0,-0.15)node{$O'$}; \fill(P)circle(0.03); \draw(P)++(\lam+\ps+90-\ps:0.15)node{$P$}; \fill(0,0)circle(0.03); \draw(0,-0.15)node{$C$}; \fill(Q)circle(0.03); \draw(Q)++(0,-0.15)node{$Q$}; \draw[dotted,<->](F1)++(\tt:-0.5)--++(90+\tt:\h); \draw(F1)++(\tt:-0.6)++(90+\tt:\h/2)node{$h$}; \end{tikzpicture} \end{document}