Device with a beam of charged particles

A device having a charged particle beam that is used for measuring the dimensions, etc. of fine circuit patterns in a semiconductor manufacturing process, at which the defocus and astigmatism, during changes in operating conditions of a as a deflection direction of the secondary signals such as secondary electrons acting Wien filter are generated, corrections are made and wherein the display dimensions obtained images are kept constant. In the apparatus, a beam of charged particles, the Wien filter (23) is arranged between a detector and a lower two stages of lenses on the side of the test sample lens (11), for converging a charged particle beam, arranged and is a computer apparatus (93) for the locked control of the Wien filter (23) and, arranged under the two stages of lenses on the side of the source of charged particles lens (12).