Global Patent Index - EP 1649488 A2

EP 1649488 A2 20060426 - QUADRUPOLE MASS FILTER

Title (en)

QUADRUPOLE MASS FILTER

Title (de)

QUADRUPOL-MASSENFILTER

Title (fr)

FILTRE DE MASSE QUADRIPOLAIRE

Publication

EP 1649488 A2 20060426 (EN)

Application

EP 04767964 A 20040730

Priority

  • GB 2004003340 W 20040730
  • GB 0317953 A 20030731

Abstract (en)

[origin: GB2390222A] Apparatus and method to improve the filtering action of a quadrupole mass filter by reducing a precursor fault caused by asymmetric electrical field between a pair of opposing electrode rods 13 in a y-axis of the quadrupole mass filter. Processing means for processing detector data determine the filtering action of the quadrupole mass filter by checking for a precursor fault. If a precursor fault in detected the power supply control means 10 introduce an AC potential difference across the electrode rods 13 in the y-axis in order to reduce asymmetry in the electric field in the y-axis. Depending on the success of the provided potential difference, additionally a DC potential difference may also be provided. Such precursor faults may be caused by misalignment of the electrode rods 13 at assembly or during use, or surface charge or contamination of the electrode rods.

IPC 1-7

H01J 49/42

IPC 8 full level

H01J 49/42 (2006.01)

CPC (source: EP)

H01J 49/0031 (2013.01); H01J 49/4215 (2013.01)

Citation (search report)

See references of WO 2005013312A2

Designated contracting state (EPC)

AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PL PT RO SE SI SK TR

DOCDB simple family (publication)

GB 0317953 D0 20030903; GB 2390222 A 20031231; GB 2390222 B 20040519; EP 1649488 A2 20060426; WO 2005013312 A2 20050210; WO 2005013312 A3 20060105

DOCDB simple family (application)

GB 0317953 A 20030731; EP 04767964 A 20040730; GB 2004003340 W 20040730