Specimen holder for a corpuscular-beam apparatus

Abstract

A corpuscular-beam apparatus including a specimen holder having at least two degrees of freedom of translation and at least one degree of freedom of rotation, and control means for correcting the translational coordinates of the specimen holder automatically when the specimen holder is rotated and retaining a predetermined specimen point in its position in the apparatus. The improvement of the invention comprises the control means comprising means for controlling the rotational movement of the specimen holder stepwise in angular increments, the angular increments being chosen small so that the translational movement of the specimen point for each angular increment may be considered linear. The control means further comprises means for correcting the translational coordinates of the specimen holder stepwise in linear increments prior to each stepwise rotation of the specimen holder, each of the linear increments comprising a linear function of the instantaneous values of the translational coordinates and of the angular increments of the rotational movement of the specimen holder.

Dependencies are inferred from the claim text.