field ion microscopy atom probe field ion microscopy AP field ionization microscopy AP field-ionization microscopy atom-probe field-ion microscopy atom probe field-ionisation microscopy AP field ionisation microscopy AP FIM AP field-ionisation microscopy atom probe field-ion microscopy atom probe field-ionization microscopy CHMO:0000099 Microscopy where atoms in the vicinty of the specimen (which is in the form of a very sharp tip <10 m diameter) are ionised by the application of a strong electric field to the tip and an image is produced by the projection of the ions onto a fluorescent screen. The image consists of a pattern of spots of light which correspond to individual atoms on the specimen surface. When a sudden voltage pulse is applied to the tip, atoms from the surface of the specimen itself are be ejected and travel down a drift tube where their arrival time (a measure of the mass of the atom) can be determined. This allows the atomic composition of the specimen to be determined. AP/FIM AP-FIM APFIM AP field-ion microscopy atom probe field ionization microscopy atom probe field ionisation microscopy