An optical device includes an apparatus for laterally shifting an optical beam. The optical device may be used in a focusing apparatus coupling an optical beam from a source waveguide to a receiving waveguide. The device may be an optical isolator that is mounted on supports that are slidably engaged with one another. The engagement may be at curved surfaces, to allow one support to rotate relative to the other. By rotating the optical isolator, a beam from the source waveguide and focused through the isolator may be selectively steered to couple it into the second waveguide. Such beam steering may be useful where the second waveguide has been misaligned from its optimum location. The beam steering may also be used to correct for post-weld displacement, where a lens of the focusing apparatus or other optical component has been misaligned during assembly. By using a rotating isolator, instead of the common multi-lens focusing apparatus, the coupling between source and receiving waveguides is far less susceptible to device alignment shifts.