Abstract: A beam splitter includes first and second prisms. The first prism includes first, second, and third optical surfaces. The second prism includes three surfaces, one of which faces the second surface of the first prism and both transmit and reflect light. The first surface of the first prism is curved and forms a lens for focusing light either transmitted or reflected by the common interface between the two prisms. The first prism is from a single piece of material. Fabrication includes making two cuts through a lens to cut-out an intermediate section. A portion of the intermediate section is cut-off to form the third surface of the first prism. The first surface of the first prism corresponds to the curved top surface of the lens. The second surface of the first prism corresponds to the bottom plano surface of the lens. The first and second prisms are then combined.