1. A method of recording a surface relief microstructure in a record medium, the method comprising: i) causing a coherent reconstruction or replay beam to impinge on a holographic optical element assembly, the holographic optical element assembly including a holographic optical element (HOE), the assembly causing selected portions of the beam to interfere at a focal region after diffraction by the holographic optical element so as to reconstruct a real image of an aperture previously used to construct the HOE; ii) locating a record medium at the focal region so that the real image is recorded; and, iii) causing relative movement between the record medium and the interfering beam portions and repeating steps i) and ii) so that the real image is recorded at a plurality of locations or pixels on the record medium.