An optical branching component particularly suitable for use as a tap device is described. The component has two optical waveguides coupled between two optical couplers which each include at least one MMI supporting at least two guided modes. There is an effective optical path length
A 1.times.2 splitter design having low loss is described. The splitter has a non-adiabatic tapered waveguide (22) connected between a substantially single-mode input waveguide (20) and two output waveguides (24, 26). The non-adiabatic tapered waveguide widens in width towards the output
