Analysis of diffraction efficiency of a holographic coupler with respect to angular divergence

摘要

We present a method to optimize the Coupling efficiency between twofibers using a Holographic Coupler taking diffraction effect into account. For thiswe obtain expressions for field distributions at the end facet of a fiber. Theresults obtained by using the expression is found to be in good agreement with thefinite element method in literature, the small deviation is attributed to thenegligence of field in the cladding. We then use the Kogelnik theory to obtainuseful formulae suitable for diffracted optical elements. The diffraction efficiencyexpressions are then used to predict the different parameters of Holograting so asto get maximum diffraction efficiency in a direction where the field distributionfrom the end facet is minimum thereby increasing the coupling efficiency.