Method and apparatus for spectrochemical analysis

US6813019B2 · kind B2 · utility

Assignee

• Varian Australia Pty Ltd · AU

Inventors

• Michael Ron Hammer · Sassafras, AU
• Philip Valmont Wilson · Camerons Flat, AU
• Mark Williams · San Jose, US
• Dower C. Bricker · Cockatoo, AU
• Martin K. Masters · Cockatoo, AU
• Stewart R. Campbell · Forest Hill, AU
• Peter Layton · Forbes, AU

Key dates

• Filing date: Oct 5, 2001
• Grant date: Nov 2, 2004
• Expiry date: Aug 2, 2022

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N21/31
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method and apparatus for the spectrochemical analysis of a sample in which a solid state array detector (82) is used to detect radiation (62) of spectrochemical interest. The invention involves the use of a shutter (72) adjacent the entrance aperture (70) of a polychromator (74-80) to expose the detector (82) to the radiation (62) for varying lengths of time whereby for short duration exposure times charge accumulation in elements (i.e. pixels) of the detector (82) due to high intensity components of the radiation is limited and for longer exposure times charge accumulation in elements (pixels) of the detector (82) due to feeble intesity components of radiation (62) is increased. This ensures that each reading of the detector (82) includes at least one exposure in which the amount of charge accumulated at each wavelength of interest is neither too little or too great. The problems of feeble radiation components not being accurately measurable and of high intensity radiation components exceeding the charge carrying capacity of elements (pixels) of the detector (82) are thereby able to be avoided. An attenuator (90) may be placed between the radiation source (60) and the detector (…