Optimisation du couplage optique par modification des bouts des fibres optiques

Abstract

Several techniques of centring a microlens onto the fibre optic end face are studied. In most of them, microsphere lenses are centred with the aid of high-accuracy micro-positioners. This process is complicated with regard to the difficulty in manipulating microsphere lenses. In this thesis, a simple and accurate self-centring method for mounting microsphere lenses using a concave cone etched fibre is described. This technique allows the centring of a wide variety of microlens radii, typically 7 μm to over 24 μm. The proposed process, however, is not affected by any spatial positioning control of microspheres. In over 85% of the attempts, the microsphere lenses were centred on the fibre axis to within 0.12 μm. Since the residual intrinsic eccentricity are minimized, the coupling effciency increase and would be over 74%.