The effect of the fused cladding shape in the coupler performance, the fact of the fused cladding being elliptical rather than circular was investigated. The associated supermodes were computed using a scalar finite element formulation in conjunction with the efficient radiation boundary condition as well as the adaptive refinement approach. The symmetric 2×2 fused coupler was analyzed and the effect of the cladding shape in the design of this structure was identified. As numerical tool, finite element approach was used taking advantage of the matrices sparsity and refinement.