An apparatus for directing light beams onto a target comprising a beam splitter for splitting a main beam into a first split beam and a second split beam; a first beam path for the first split beam, the first beam path including a first aperture, a first lens and a second lens; a second beam path for the second split beam, the second beam path including a second aperture, a third lens and a fourth lens; a plurality of mirrors arranged such that the first split beam and the second split beam intersect at the target. An apparatus can also include means for placing a target in the image plane of a first aperture and a second aperture.