Reflectance Mueller matrix (MM) polarimetry is being used to characterize biological media in multiple clinical applications. The origin of the reflectance polarimetric data is often unclear due to the impact of multiple scattering and tissue heterogeneity. We have developed a new, to the best of our knowledge, multimodal imaging technique combining MM reflectance, MM digital confocal imaging, and co-registered nonlinear microscopy techniques. The instrument unveils the origin of reflectance polarimetric signature in terms of confocal reflectance data. The reconstructed reflected MM demonstrates the capability of our method to provide depth-resolved 3D polarization response from complex biological media in terms of depolarization, retardance, and orientation parameters.
Mueller matrix polarimetry (MMP) is a promising linear imaging modality that can enable visualization and measurement of the polarization properties of the cornea. Although the distribution of corneal birefringence has been reported, depth resolved MMP imaging of the cornea has not been archived and remains challenging. In this work, we perform depth-resolved imaging of the cornea using an improved system that combines Mueller matrix reflectance and transmission microscopy together with nonlinear microscopy utilizing second harmonic generation (SHG) and two photon excitation fluorescence (TPEF). We show that TPEF can reveal corneal epithelial cellular network while SHG can highlight the presence of corneal stromal lamellae. We then demonstrate that, in confocal reflectance measurement, as depth increases from 0 to 80
- NSF-PAR ID:
- 10195744
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Biomedical Optics Express
- Volume:
- 11
- Issue:
- 10
- ISSN:
- 2156-7085
- Page Range / eLocation ID:
- Article No. 5982
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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