×

Arrangement and process for adjusting imaging systems

  • US 4,486,664 A
  • Filed: 07/26/1982
  • Issued: 12/04/1984
  • Est. Priority Date: 07/31/1981
  • Status: Expired due to Fees
First Claim
Patent Images

1. Arrangement for adjusting an imaging system for bundles of charged particles, or for adjusting a spectrometer for bundles of charged particles, by means of one or more electrostatic correcting elements, characterised in that each of these correcting elements possesses a large number (N) of electrodes, which are arranged, symmetrically or asymmetrically, around the optical axis (Z) of the particle bundle, and are at potentials such that the resulting potential (V(r,Φ

  • )) at an azimuth angle (Φ

    ) relative to a cylindrical surface at a specified radius (r) around a straight optical axis (Z) or, as the case may be, relative to a corresponding toroidal surface around a curved axis, can be represented as the sum of
    
    
    space="preserve" listing-type="equation">V.sub.1 =V.sub.11 sin Φ

    +V.sub.12 sin 2Φ

    +V.sub.13 sin 3Φ

    +V.sub.14 sin 4Φ

    +V.sub.15 sin 5Φ

    +V.sub.16 sin 6Φ

    and
    
    
    space="preserve" listing-type="equation">V.sub.2 =V.sub.21 cos Φ

    +V.sub.22 cos 2Φ

    +V.sub.23 cos 3Φ

    +V.sub.24 cos Φ

    +V.sub.24 cos 4Φ

    +V.sub.25 cos 5Φ

    +V.sub.26 cos 6Φ

    it being possible to set the coefficients V1k and V2k, as desired, by selecting values for k from k=1 to 6, so that the potentials represent a superposition of an electric dipole, of a quadrupole, of a hexapole, of an octapole, of a decapole, and/or of a duodecapole, the orientation and strength of each individual multipole, relative to the angle Φ

    =0, being in every case adjustable as desired.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×