| 摘要 |
PCT No. PCT/SU79/00098 Sec. 371 Date Jun. 16, 1981 Sec. 102(e) Date Jun. 16, 1981 PCT Filed Oct. 18, 1979 PCT Pub. No. WO81/01228 PCT Pub. Date Apr. 30, 1981.A device for scanning a beam of charged particles comprises longitudinal and cross-sectional scanning electromagnets (1,4) to deflect the beam, respectively, lengthwise and crosswise over the exit window (2), longitudinal and cross-sectional scanning current generators (5, 6) to energize the respective electromagnets (1, 4), and a variable delayer (7) connected between the longitudinal scanning current generator (5) and the synchronizing input of the cross-sectional scanning current generator (6) so that pulses arrive at the input of the variable delayer (7) at the moments when current in the windings of the electromagnet (1) reaches its peak. The variable delayer (7) provides N delay times different from each other by a value of DELTA t and set in succession as the pulses arrive at its input, the values N and DELTA t being determined from the following relationships: DELTA t</=d/2f1L; N>/=1/f2 DELTA t where d-diameter of the charged particle beam, f1-frequency of the longitudinal scanning, f2-frequency of the cross-sectional scanning, L-value of maximum deflection of the beam along the length of the exit window.
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