$//<![CDATA[ \begin{array}{l}\displaystyle \mu_{ob}(R_s) = 10^A \cdot \left( \mu_{od} \right)^B\end{array} //]]>$,  $//<![CDATA[ \begin{array}{l}A = R_s \cdot ( c_1 \, R_s + c_2 )\end{array} //]]>$, $//<![CDATA[ \begin{array}{l}B = c_3 \, D^{c_4} + c_5 \, D^{c_6} + c_7 \, D^{c_8}\end{array} //]]>$, $//<![CDATA[ \begin{array}{l}D = 10^{-R_s}\end{array} //]]>$

$//<![CDATA[ \begin{array}{l}c_1 = 2.2 \cdot 10^{-7}, \ c_2 = -7.4 \cdot 10^{-4}, \ c_3 =0.68, \ c_4 = 8.62 \cdot 10^{-5}, \ c_5 = 0.25, \ c_6 = 1.1 \cdot 10^{-3}, \ c_7 = 0.062, \ c_8 = 3.74 \cdot 10^{-3}\end{array} //]]>$