ABSTRACT
Dual rotating-compensator Mueller matrix polarimetry (DRC-MMP) has achieved wide spread applications in material characterization, nano-scale measurement, and biomedical diagnostics. However, the traditional calibration method for DRC-MMP relies on establishing an accurate system model, making its implementation cumbersome, especially in the presence of polarizing components that are to complex to be modeled. We propose a novel, to the best of our knowledge, eigenvalue calibration method for DRC-MMP without system modeling. Two specific basis vectors are introduced in order to transform the continuously modulated light intensity in DRC-MMP into a 5×5 projection matrix. Eigenvalue analysis is then performed based on the light intensity projection matrix to obtain the modulation matrix and the analysis matrix associated with the polarization state generator and the polarization state analyzer, respectively. The method is applied for DRC-MMP in both single-pass and double-pass setups. The experimental results have verified the proposed calibration method.
ABSTRACT
The rigid registration is a key step of Image Guided Surgery (IGS), and the point-pair method is the main way used for registration. However the configuration of fiducial points has a great influence on the registration accuracy at the target point. Now almost all the optimization method of fiducial points configuration relies on the empirical simulation-based Fitzpatrick's target registration error (TRE). In this paper, a phantom and some markers were designed and some experiments were conducted to measure and compare the affecting factors on the registration. By the markers repeated selections, the fiducial location error (FLE) has a small deviation of maximum 0.4 mm, and the average of the Fitzpatrick's TRE (F-TRE) has almost 86% proportion to the average of the actual TRE (A-TRE), but the standard deviation (STD) just has 7% proportion. Also, the experiment result showed that six fiducial markers already had the 86% accuracy, and spreading the fiducial markers led to 30% reduction in mean of A-TRE and 40% reduction in STD of A-TRE comparing with the centralized. Overall, to find a strategy of optimization, reducing the TRE has the great meaning to support safer and more accurate minimally IGS procedures.
