X-Git-Url: http://git.kpe.io/?a=blobdiff_plain;f=doc%2Fctsim-concepts.tex;h=21f94ddec9e999d3d39ea3f09613f51bbf824f0d;hb=464c5028a9dd12b75fc05ea80fdf124af2bcbb01;hp=9653a120ead80b7343711c9699b6a87b9dc600f9;hpb=dc60803b173bcf8719862fbed7e8652883e23f96;p=ctsim.git diff --git a/doc/ctsim-concepts.tex b/doc/ctsim-concepts.tex index 9653a12..21f94dd 100644 --- a/doc/ctsim-concepts.tex +++ b/doc/ctsim-concepts.tex @@ -39,7 +39,7 @@ phantom. Each line contains seven entries, in the following form: element-type cx cy dx dy r a \end{verbatim} The first entry defines the type of the element, either -\rtfsp\texttt{rectangle}, \texttt{}, \texttt{triangle}, +\rtfsp\texttt{rectangle}, \texttt{ellipse}, \texttt{triangle}, \rtfsp\texttt{sector}, or \texttt{segment}. \texttt{cx}, \rtfsp\texttt{cy}, \texttt{dx} and \texttt{dy} have different meanings depending on the element type. @@ -114,10 +114,10 @@ variable is the diameter of the circle surround the phantom, or the \emph{phantom diameter}. Remember, as mentioned above, the phantom dimensions are also padded by 1\%. -The other important geometry variables for scanning objects are the -\emph{view ratio}, \emph{scan ratio}, and \emph{focal length ratio}. -These variables are all input into \ctsim\ in terms of ratios rather -than absolute values. +The other important geometry variables for scanning phantoms are +the \emph{view diameter}, \emph{scan diameter}, and \emph{focal +length}. These variables are all input into \ctsim\ in terms of +ratios rather than absolute values. \subsubsection{Phantom Diameter} \begin{figure} @@ -165,7 +165,7 @@ By default, the entire \emph{view diameter} is scanned. For experimental purposes, it may be desirable to scan an area either larger or smaller than the \emph{view diameter}. Thus, the concept of \emph{scan ratio}, \latexonly{$s_r$,}\latexignore{\emph{SR},} -is born. The scan diameter +is arises. The scan diameter \latexonly{$s_d$}\latexignore{\emph{Sd}} is the diameter over which x-rays are collected and is defined as \latexonly{$$s_d = v_d s_r$$}\latexignore{\\$$\emph{Sd = Vd x SR}$$\\} By default and @@ -260,9 +260,9 @@ Since in normal scanning $s_r$ = 1, $\alpha$ depends only upon the \subsubsection{Detector Array Size} In general, you do not need to be concerned with the detector -array size. It is automatically calculated by \ctsim. For those -interested, this section explains how the detector array size is -calculated. +array size. It is automatically calculated by \ctsim. For the +particularly interested, this section explains how the detector +array size is calculated. For parallel geometry, the detector length is equal to the scan diameter.