A method and apparatus is provided for writing a code on an optical element, wherein the code is written on the optical element in the form of a holographic image of an n-dimensional code generated by an interference pattern between a reference beam and a signal beam reflected off a spatial light modulation device having the n-dimensional code configured thereon. The method includes steps of generating the interference pattern between the reference beam and the signal beam reflected off the spatial light modulation device having the n-dimensional code thereon; as well as writing the interference pattern on the optical element as a holographic image of the n-dimensional code.