Self-aligned setup for laser optical feedback imaging insensitive to parasitic optical feedback

Abstract

In this paper we propose a new optical architecture for the laser optical feedback imaging (LOFI) technique which makes it possible to avoid the adverse effect of the optical parasitic backscattering introduced by all the optical interfaces located between the laser source and the studied object. This proposed setup need no specific or complex alignment, that why we can consider the proposed setup as self aligned. We describe the principle used to avoid the parasitic backscattering contributions which deteriorate dramatically amplitude and phase information contained in the LOFI images. Finally, we give successful demonstration of amplitude and phase images obtained with this self aligned setup in presence of a parasitic reflection.