Our beam expanders with fixed expansion factor offer certain advantages compared to systems consisting of only two single lenses. For collimation, we use either an air spaced two lens system or an achromat in order to minimize chromatic and spherical aberrations and reach diffraction limited performance. In addition, the divergence of the expanded beam can be easily adjusted. The design is Galilean type, i.e. there is no internal focus and the system length is short compared to a Kepler type system.