Abstract

Lensless endoscopes provide means for delivery and collection of light to and from tissue without any need for additional optical elements at the fibre distal end [1]. This requires a comprehensive investigation of the optical beam propagation through the fibre, since any focussing or scanning at the sample site requires the beam to be shaped at the fibre proximal end. The beam delivery and collection must be stable towards fibre bending for an accurate imaging system. In this context, the experimental acquisition of Transformation Matrix (TM) could lead to deterministic optical propagation even in non-ideal fibre structures [2,3], although one could only rely on this method after choosing the fibre for the current purpose. Even though this model has been used previously to experimentally predict the light propagation through a straight fibre [2] and then theoretically for significantly deformed segments of multimode fibres [3], an opportunity to choose a better-suited optical fibre for the specific application is not given by the TM method. We present a numerical tool to simulate various types of optical fibre under the realistic use case of bending deformations, which in turn allows the user to choose the best optical fibre with suitable parameters for the specific application before starting the experiment.

© 2019 IEEE