Back to results
US 4,837,434 AGranted
Mass spectrometry system and method employing measurement/survey scan strategy
AssigneeHewlett-Packard Company
InventorCraig A. James
Life of this patent
Estimating the term…
Abstract
A gas chromatography plus mass spectrometry system implements a scan strategy in which each full range scan alternates between a normal measurement mode and a survey mode based on a block/gap map made during the previous scan. Survey mode is used within regions that were determined in the previous scan to lack signal above a predetermined threshold. Spectral data is generated during measurement mode operation. Each scan serves both measurement and mapping functions in a way that avoids mass filter jumps, since each scan is monotonic over the entire scanning range.
Claims8
A system comprising:
- means for receiving a sample;
- scanning means for repeatedly monotonically scanning said sample over a predetermined scanning range so as to obtain a series of spectra, said scanning means having alternate survey and measurement modes, said survey mode being characterized by a faster scanning rate than said measurement mode;
- output means for indicating spectral data gathered during the measurement mode for each scan taken by said scanning means;
- map means for generating a map during a scan by said scanning means so that said predetermined scanning range is divided into signal and blank regions according to a predetermined threshold criterion;
- and
- mode means for switching between said survey mode and said measurement mode during a monotonic scan over said predetermined scanning range by said scanning means at least in part as a function of the map generated by said map means during a preceding scan over said predetermined scanning range;
- wherein a spectral chromatogram can be obtained using a series of monotonic scans, said series including at least some scans serving the dual functions of measuring in accordance with a map generated by a preceding scan and of surveying to generate a map to be used by a succeeding scan.
4 more elements
A method comprising:
- introducing a sample into a spectrometer;
- scanning said sample repeatedly and monotonically over a predetermined spectral range;
- during each of several successive scans, generating a map indicating signal and blank regions according to a predetermined threshold criterion;
- during the succeeding scan, switching between survey and measurement mode as determined at least in part by the map generated during the preceding scan;
- and
- outputting as data measurements taken during measurement mode operation within each scan.
3 more elements
Dependencies are inferred from the claim text.