Abstract: Space savings are effected in the optical output system of a laser velocimeter. The output system comprises pairs of optical fibers having output ends from which a beam of laser light emerges, a transfer lens for each light beam, and at least one final (LV) lens for receiving the light passing through the transfer lenses and for focussing that light at a common crossing point or area. In order to closely couple the transfer lenses to the final lens, each transfer lens is positioned relative to the final lens receiving light therefrom such that the output waist of the corresponding beam received by the final lens from the transfer lens is a virtual waist located before the transfer lens.

Abstract: A beam focusing and positioning apparatus provides focusing and positioning the final waist of a gaussian beam at a desired location on a target such as an optical fiber. The apparatus includes a first lens, having a focal plane f.sub.1, disposed in the path of an incoming beam and a second lens, having a focal plane f.sub.2 and being spaced downstream from the first lens by a distance at least equal to f.sub.1 +10f.sub.2, which cooperates with the first lens to focus the final waist of the beam on the target. A rotatable optical device, disposed upstream of the first lens, adjusts the angular orientation of the final beam waist by a parallel displacement of the beam at said optical device.