The multiplexer includes multi-mode waveguides positioned on a base such that a plurality of the waveguides serve as input waveguides and one or more of the waveguides serve as an output waveguide. The waveguides intersect one another such that light signals traveling along a plurality of the input waveguides are combined onto an output waveguide. At least a portion of the input waveguides including a taper configured to taper the width of a light signal traveling along the input waveguide toward the output waveguide.