Jérémy Vizet

Demonstration of full 4×4 Mueller polarimetry through an optical fiber for endoscopic applications.

A novel technique to measure the full 4 × 4 Mueller matrix of a sample through an optical fiber is proposed, opening the way for endoscopic applications of Mueller polarimetry for biomedical diagnosis. The technique is based on two subsequent Mueller matrices measurements: one for characterizing the fiber only, and another for the assembly of fiber and sample. From this differential measurement, we proved theoretically that the polarimetric properties of the sample can be deduced. The proof of principle was experimentally validated by measuring various polarimetric parameters of known optical components. Images of manufactured and biological samples acquired by using this approach are also presented.

Optical fiber-based full Mueller polarimeter for endoscopic imaging using a two-wavelength simultaneous measurement method

Abstract. This paper reports a technique based on spectrally differential measurement for determining the full Mueller matrix of a biological sample through an optical fiber. In this technique, two close wavelengths were used simultaneously, one for characterizing the fiber and the other for characterizing the assembly of fiber and sample. The characteristics of the fiber measured at one wavelength were used to decouple its contribution from the measurement on the assembly of fiber and sample and then to extract sample Mueller matrix at the second wavelength. The proof of concept was experimentally validated by measuring polarimetric parameters of various calibrated optical components through the optical fiber. Then, polarimetric images of histological cuts of human colon tissues were measured, and retardance, diattenuation, and orientation of the main axes of fibrillar regions were displayed. Finally, these images were successfully compared with images obtained by a free space Mueller microscope. As the reported method does not use any moving component, it offers attractive integration possibilities with an endoscopic probe.

One shot endoscopic polarization measurement device based on a spectrally encoded polarization states generator

We report a novel technique for polarimetric characterization of samples through a flexible fiber endoscope, with a single shot measurement per pixel. The sample is simultaneously probed with a large diversity of polarization states, and both degree of polarization and linear retardance are determined thanks to specific processing of data. The probe polarization states are spectrally encoded on the 10 nm bandwidth of the source. The key component of the endoscope is a 3 m long specially designed optical fiber which consists of the optimized concatenation of highly birefringent fiber pieces. For a proof of principle, different calibrated or manufactured samples were successfully characterized. The proposed technique is attractive in view of reducing the measurement time of polarimetric images, in endoscopic applications.

Demonstration of Mueller polarimetry through an optical fiber for endoscopic applications

We present very first measurements of Mueller matrices of samples through an optical fiber, opening the way to endoscopic applications for early detection of diseases. The technique is based on measurements of both the single fiber and the assembly fiber+sample Mueller matrices. The 2m optical guide is made of two identical pieces of PM fiber spliced with crossed fast and slow axes in order to (i) minimize residual phase retardance at the output, (ii) and precisely know the eigen axes orientations. Mueller matrices of different calibrated samples are measured, leading to accurate and reliable determination of combined birefringence, diattenuation and depolarization of these samples.

Special Section Guest Editorial:Antonello De Martino (1954–2014): in memoriam

This PDF file contains the editorial “Special Section Guest Editorial:Antonello De Martino (1954–2014): in memoriam” for JBO Vol. 21 Issue 07

Polar decompositions of negative-determinant Mueller matrices featuring nondiagonal depolarizers

We generalize an existing algebraic procedure for the polar decomposition of Mueller matrices with negative determinants [Opt. Commun.281, 2406 (2008)OPCOB80030-401810.1016/j.optcom.2007.12.076] to the case of nondiagonal depolarizer matrix factors. The generalized procedure is applied to experimental Mueller matrices illustrating its potential for the phenomenological interpretation of complex polarimetric data.