Direct measurement of the scattering coefficient
Martin Hohmann, Benjamin Lengenfelder, Daniel Muhr, Moritz Späth, Maximilian Hauptkorn, Florian Klämpfl, Michael Schmidt
Abstract
In general, the measurement of the main three optical properties ( µ a , µ s and g ) in turbid media requires a very precise measurement of the total transmission (TT), the total reflection (TR) and the collimated transmission (CT). Furthermore, an inverse algorithm such as inverse adding doubling or inverse Monte-Carlo-simulations is required for the reconstruction of the optical properties. Despite many available methods, the error free measurement of the scattering coefficient or the g-factor still remains challenging. In this study, we present a way to directly calculate the scattering coefficient from the total and collimated transmission. To allow this, it can be shown that <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mfrac> <mml:mrow> <mml:mi>T</mml:mi> <mml:mi>T</mml:mi> </mml:mrow> <mml:mrow> <mml:mi>C</mml:mi> <mml:mi>T</mml:mi> </mml:mrow> </mml:mfrac> </mml:math> is proportional to <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:msup> <mml:mi>e</mml:mi> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:msub> <mml:mi>μ</mml:mi> <mml:mi>s</mml:mi> </mml:msub> <mml:mo>⋅</mml:mo> <mml:mi>d</mml:mi> </mml:mrow> </mml:msup> </mml:math> for a wide range of optical properties if the sample is thick enough. Moreover, a set-up is developed and validated to measure the collimated transmission precisely.