Patent · US Expired

Method of gain regulation for downhole spectroscopy tools without using a calibration source

US5360975A · kind A · utility

31Cited by
12References
29Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 23, 1993
Grant dateNov 1, 1994
Priority date
Expiry dateApr 23, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01V5/04
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The present invention provides a method of stabilizing the gain of spectroscopy equipment using the actual measured spectrum of the formation of interest and thereby eliminating the need to use external radioactive calibration sources. The gain is measured and adjusted using spectral fitting techniques. In these techniques, an energy spectrum of the radiation from an earth formation is measured. The measured spectrum is compared to a standard spectrum or composite spectrum. As a result of the comparisons, deviations between corresponding features of the two spectra are determined. Gain correction signals are calculated based on the determined deviations. The gain of the spectroscopy equipment is adjusted based on these calculated correction signals.

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