The feasibility of optical recording by irradiating diamond with energetic
ion beams has been investigated. The radiation damage in the exposed target
areas provides sufficient optical contrast to the unexposed parts as to di
stinguish analog or digital patterns by visible light. The physical propert
ies of the radiation effects have been studied by a variety of experimental
techniques, including optical transmission and luminescence, photo-thermal
deflection spectroscopy, infrared and Raman spectroscopy, and ion beam cha
nneling in conjunction with atomic force measurements. The important result
is that permanent data storage in diamond is possible with high pixel dens
ities. A unique feature of diamond, irradiated up to and beyond a critical
ion fluence, is the thermal phase transformation to its allotropic form of
graphite. This feature can be used to enhance optical contrast at sub-amorp
hization irradiation levels. Estimates on the pixel density of data recordi
ng in diamond are presented and the necessity of developing large-area diam
ond wafers of high optical quality is emphasized.