## 3 Results and Discussion
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{3}{*}{**Type**} & \multirow{3}{*}{**Tissues**} & \multicolumn{6}{c}{**Linear Retardance**} \\ \cline{3-8}  & & \multicolumn{3}{c}{\(R^{2}\)} & \multicolumn{3}{c}{\(p\)} \\ \cline{3-8}  & & \(\delta\)\(-\)\(t_{2434}\) & \(\delta\)\(-\)\(t_{243}\) & \(\delta\)\(-\)\(t_{qr}\) & \(\delta\)\(-\)\(t_{2434}\) & \(\delta\)\(-\)\(t_{2434}\) & \(\delta\)\(-\)\(t_{qr}\) \\ \hline \multirow{8}{*}{Forward} & colorectal & 0.97 & 0.94 & 0.99 & \(<\)0.01 & \(<\)0.01 & \(<\)0.01 \\  & ITB & 0.93 & 0.93 & 0.97 & \(<\)0.01 & \(<\)0.01 & \(<\)0.01 \\  & liver & 0.98 & 0.99 & 0.99 & \(<\)0.01 & \(<\)0.01 & \(<\)0.01 \\  & CD & 0.91 & 0.93 & 0.93 & \(<\)0.01 & \(<\)0.01 & \(<\)0.01 \\  & bladder & 0.99 & 0.99 & 0.99 & \(<\)0.01 & \(<\)0.01 & \(<\)0.01 \\  & breast & 0.90 & 0.91 & 0.99 & \(<\)0.01 & \(<\)0.01 & \(<\)0.01 \\  & adenoma & 0.97 & 0.94 & 0.99 & \(<\)0.01 & \(<\)0.01 & \(<\)0.01 \\  & Total & 0.98 & 0.98 & 0.99 & \(<\)0.01 & \(<\)0.01 & \(<\)0.01 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Correlation and statistical analysis comparison results between forward measured MMT and MMPD linear retardance parameters for each kind of thin tissue sample. Figure 3: Comparison of MMT and MMPD linear retardance parameters of thin tissue samples. (**a**) Linear retardance MMPD parameter \(\delta\) plotted against its counterpart MMT parameter \(t_{2434}\) for correlation analysis with all seven kinds of thin tissue samples. (**b**) Statistical analysis bar chart of linear retardance MMPD parameter \(\delta\) and MMT parameter \(t_{2434}\) for each kind of thin tissue samples. (**c**) Linear retardance MMPD parameter \(\delta\) plotted against its counterpart MMT parameter \(t_{24243}\) for correlation analysis with all seven kinds of thin tissue samples. (**d**) Statistical analysis bar chart of linear retardance MMPD parameter \(\delta\) and MMT parameter \(t_{4243}\) for each kind of thin tissue samples. (**e**) Linear retardance MMPD parameter \(\delta\) plotted against its counterpart MMT parameter \(t_{qr}\) for correlation analysis with all seven kinds of thin tissue samples. (**f**) Statistical analysis bar chart of linear retardance MMPD parameter \(\delta\) and MMT parameter \(t_{qr}\) for each kind of thin tissue sample. Quantitative Comparison of Linear Retardance Related MMPD and MMT Parameters for Backscattering Imaging of Bulk Tissue Samples  
As shown in Table 5, for the backscattering measurement results of bulk tissue samples, the linear retardance related parameters derived from MMT and MMPD methods do not show a good correlation. The correlation coefficient values of each kind of bulk tissue samples for parameter groups (\(\delta\), \(t_{2434}\)), (\(\delta\), \(t_{4243}\)) and (\(\delta\), \(t_{qr}\)) are between 0.16 and 0.89, and we can also see the data points of the tissue samples distribute randomly in Figure 4a,c,e. Besides, Figure 4b,d,f show that the MMPD linear retardance parameters are larger than the MMT linear retardance parameters, and they all have statistically significant differences with the \(p\)-value smaller than 0.05. Therefore, it is worth mentioning that when we try to measure linear retardance property of bulk tissues sample using backscattering polarimetry, the MMPD parameter \(\delta\) will provide the information more accurately, while the MMT linear retardance parameters can be suitable for quickly evaluating the existence and location of birefringent structures. Quantitative Comparison of Linear Birefringence Orientation Related MMPD and MMT Parameters for Transmission Imaging of Thin Tissue Samples  
Besides the linear retardance value, the fast axis orientation of linear birefringence is another important indicator to reveal the structural features of tissue, such as the distribution behaviors of collagen and elastic fibers in pathological tissue samples, which is helpful for clinical diagnosis.