which completely contains the phantom. Let $l_p$ be the width (or height)
of this square.
-\subsubsection{Focal Length & Field of View}
+\subsubsection{Focal Length \& Field of View}
The two other important variables are the field-of-view-ratio ($f_{vR}$)
and the focal-length-ratio ($f_{lR}$). These are used along with $l_p$ to
define the focal length and the field of view (not ratios) according to
transform of the projection data and multiply that by the absolute(x) filter and
then perform an inverse fourier transform.
-\item{Backprojection of filtered projections}
\ No newline at end of file
+\subsubsection{Backprojection of filtered projections}
\ No newline at end of file