Extended Depth Chromatic Confocal Tomography
Abstract
To study the internal luminal organs such as the GI tract, a flexible
endoscope with a few millimeters diameter is required. Several flexible
endoscopic confocal imaging systems have been demonstrated. Unfortunately,
such images are restricted to a single plane. A mechanism for depth scanning
(z-scan) is required to achieve three-dimensional images of the tissue. Recently,
endoscopic z-scanning was achieved using variable focus lenses. Incorporating
a mechanism for z-scanning into an endoscope increases the size and complexity
of the endoscope. Using the chromatic dispersion property of light, one may
achieve a multifocal confocal microscopy system. Chromatic confocal microscopy
has been achieved using chromatic dispersion of refractive and diffractive optical
elements. A maximum imaging range of 250 μm has been achieved using
chromatic aberration of multiple achromatic and diffractive lenses. The GI tract
tissue is very irregular however and thus requires an imaging range of much more
than 250 μm. In this project, we have developed an ultralong imaging range
(2 cm) chromatic confocal microscopy system with cellular-level spatial
resolution. We used the exceptional chromatic dispersion properties of Zinc
Selenide material to achieve the extension in the imaging range.
Short Biography
Kanwarpal Singh received his Ph.D. degree from INRS, Canada, in 2013. He was a Postdoctoral Fellow at Harvard Medical School, USA, until 2018, where he worked on the development of high-resolution optical coherence tomography systems. He is a Group Leader leading an independent research group (Microendoscopy), at the Max Planck Institute for the Science of Light, Germany. His research interest includes the development of miniaturized flexible endoscopic devices for imaging inside the body.
