To evaluate the severity of airway pathologies, quantitative dimensioning of airways is of utmost importance. Endoscopic vision gives a projective image and thus no true scaling information can be directly deduced from it. In this article, an approach based on an interferometric setup, a low-coherence laser source and a standard rigid endoscope is presented, and applied to hollow samples measurements. More generally, the use of the low-coherence interferometric setup detailed here could be extended to any other endoscopy-related field of interest, e.g., gastroscopy, arthroscopy and other medical or industrial applications where tri-dimensional topology is required. The setup design with a multiple fibers illumination system is presented. Demonstration of the method ability to operate on biological samples is assessed through measurements on ex vivo pig bronchi.
In this communication we introduce a low or reduced coherence interferometry technique that can be used to
retrieve surface topology on samples with high roughness. Moreover, we will show that the approach enables
surface topology measurement also at the interface of so-called turbid media, where multiple scattering inside
tissues can be a major issue, preventing accurate measurements.
We propose to use digital holographic microscopy (DHM) with an illumination in the near infrared spectrum
bandwidth, where the silicon is known to have small absorption. With such an illumination condition, it is possible
to observe a wider range of specimens than in the visible spectrum, providing a new metrology technique for
3D silicon micro-systems characterization. Suitability of DHM with near infrared illumination for micro-optical
elements and wafer inspection is demonstrated. The intrinsic robustness and speed of the method place DHM
as a valuable candidate for real-time quality check inside production chains, opening a wide field of applications
in quality control.
We introduce Endoscopic Low Coherence Interferometry to obtain topology of upper airways through commonly
used rigid endoscopes. Quantitative dimensioning of upper airways pathologies is crucial to provide maximum
health recovery chances, for example in order to choose the correct stent to treat endoluminal obstructing
pathologies. Our device is fully compatible with procedures used in day-to-day examinations and can potentially
be brought to bedside. Besides this, the approach described here can be almost straightforwardly adapted to
other endoscopy-related field of interest, such as gastroscopy and arthroscopy. The principle of the method is first
exposed, then filtering procedure used to extract the depth information is described. Finally, demonstration of
the method ability to operate on biological samples is assessed through measurements on ex-vivo pork bronchi.