polarization1.tex

\documentclass{standalone}
%\pagenumbering{gobble}


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% schematic of light scattering off dust
% grain and becoming polarized
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


\usepackage{tikz,xcolor}
\usetikzlibrary{arrows,snakes}
\usetikzlibrary{arrows.meta}
\usetikzlibrary{shapes.geometric}
\usetikzlibrary{backgrounds}
\tikzset{
	partial ellipse/.style args={#1:#2:#3}{insert path={+ (#1:#3) arc (#1:#2:#3)}}
	}

\begin{document}

\tikzstyle{background grid}=[draw, black!30,step=.5cm]
%\begin{tikzpicture}[scale=1.0, font=\sffamily, show background grid]
\begin{tikzpicture}[scale=1.0, font=\sffamily]


	% grain
	\draw[color=white, fill=gray!30, rotate=0] (10,-3) ellipse (1 and 1);
	\node at (10,-1.3) {\large scattering};
	\node at (10,-1.7) {\large surface};

	% background star
	\node[star,star points=7,star point ratio=1.8, fill] at (0,3) {};

	% telescope
	\draw[very thick] (20,3) ellipse (0.1 and 0.5);
	\draw[very thick] (22,3) [partial ellipse=-90:90:0.1 and 0.5];
	\draw[very thick] (20,3.5) -- (22,3.5);
	\draw[very thick] (20,2.5) -- (22,2.5);
	\draw[white, fill=gray!70] (20.8,1.5) -- (21.3,2.5) -- (21.8,1.5) -- cycle;
	%\draw[ultra thick] (0.2,1.9) arc (5:55:-1.7);

	% lines of sight
	\draw[very thick, dotted, arrows={-Triangle[angle=60:10pt]}] (0,3) -- (10,-3);
	\draw[very thick, dotted, arrows={-Triangle[angle=60:10pt]}] (10,-3) -- (20,3);

	% draw electric field direction
	\draw[very thick, <->] (5,-0.75) -- (5,0.75);
	\draw[very thick, <->] (4.25,0) -- (5.75,0);
	\node at (3.6,-0.5) {\large unpolarized};
	\draw[very thick, <->] (15,-0.35) -- (15,0.35);
	\draw[very thick, <->] (14.25,0) -- (15.75,0);
	\node at (13.7,0.4) {\large polarized};

	% draw schematic of the polarization pattern
	\draw[color=black, fill=gray!10] (21.7,-0.3) -- (18.3,-0.3) -- (18.3,-3.7) -- (21.7,-3.7) -- cycle;
	\draw[fill] (20,-2) circle (0.1);
	\draw[very thick] (19,-2.3) -- (19,-1.7);
	\draw[very thick] (21,-2.3) -- (21,-1.7);
	\draw[very thick] (19.7,-1) -- (20.3,-1);
	\draw[very thick] (19.7,-3) -- (20.3,-3);
	\draw[very thick] (18.8,-1.2) -- (19.2,-0.8);
	\draw[very thick] (20.8,-0.8) -- (21.2,-1.2);
	\draw[very thick] (18.8,-2.8) -- (19.2,-3.2);
	\draw[very thick] (20.8,-3.2) -- (21.2,-2.8);
	\node at (20,-0.05) {\large polarization pattern};
	\node at (20,-3.9) {$\alpha$};
	\node at (18.1,-2) {$\delta$};

\end{tikzpicture}

\end{document}