%% 
%%  Ein Beispiel der DANTE-Edition
%%  
%%  2. Auflage
%% 
%%  Beispiel 15-03-38 auf Seite 762.
%% 
%%  Copyright (C) 2016 Herbert Voss
%% 
%%  It may be distributed and/or modified under the conditions
%%  of the LaTeX Project Public License, either version 1.3
%%  of this license or (at your option) any later version.
%% 
%%  See http://www.latex-project.org/lppl.txt for details.
%% 
%% 
%% ==== 
% Show page(s) 1
%% 
%% 
\documentclass[]{exaarticle}
\pagestyle{empty}
\setlength\textwidth{145.16928pt}
\setlength\parindent{0pt}
\usepackage[utf8]{inputenc}
%StartShownPreambleCommands
\usepackage{pst-optexp, nicefrac}
%StopShownPreambleCommands
\begin{document}
\begin{pspicture}(-4.2,-1)(3,3)
\pnode(-2,0){LOut}\pnode(0,0){Grat}
\pnode(4;45){Out}\pnode(2.5;70){Mvar}
\newpsstyle{Beam}{linewidth=2\pslinewidth,
                  linecolor=red!90!black}
\begin{optexp}
 \optbox[optboxwidth=2.2, labeloffset=0,
         position=start](LOut)(Grat){diode laser}
 \mirror[variable,label=0.5]%
        (Grat)(Mvar)(Grat){M$_\mathrm{var}$}
 \optretplate[position=0.3]%
        (LOut)(Grat){$\nicefrac{\lambda}{4}$}
 \optgrating(LOut)(Grat)(Out){grating}
 \drawbeam[arrows=->]{1}{3}{4}(Out)
 \drawbeam{2}{4}
\end{optexp}
\rput[l](-3,2){Littman setup}
\end{pspicture}
\end{document}