Patent · US Expired

Microwave plasma source

US7030979B2 · kind B2 · utility

10Cited by
4References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 23, 2002
Grant dateApr 18, 2006
Priority date
Expiry dateOct 26, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05H1/30
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A plasma source for a spectrometer includes a plasma torch (10) located within a waveguide or resonant cavity (40) for both the electric and the magnetic field components of a microwave electromagnetic field to excite a plasma (54). This produces a plasma (54) having a generally elliptical cross section into which sample is relatively easily injected but which still provides good thermal coupling between the plasma and the sample. The invention gives significantly improved limits of detection compared to prior art microwave induced plasma systems. The torch is preferably axially aligned with the direction of the magnetic field component and may be located within a resonant iris (32) within the waveguide or cavity (40).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.