Detector for a spectrometer
Method and apparatus for comparing spectra
Grouping of spectral bands for data acquisition in a spectrophotometer Patent #: 5412468
ApplicationNo. 940575 filed on 09/30/1997
US Classes:702/22, Chemical analysis356/319, Utilizing a spectrophotometer (i.e., plural beam)356/326, Utilizing a spectrometer356/328Having diffraction grating means
ExaminersPrimary: Hoff, Marc S.
Assistant: Vo, Hieu T.
Attorney, Agent or Firm
Foreign Patent References
International ClassG01R 035/00
AbstractA spectrometric instrument includes a detector with detecting subarrays on small portions of the surface. Spectral data are acquired for selected subarrays at a first time for a drift standard, and compared to a zero position to obtain first offset data. Data are acquired similarly at a second time to obtain second offset data. The offset data are utilized to obtain a spectral shift for any subarray position at any selected time. The shift is applied to a matrix model used for converting test data to compositional information. Archive data for the model is obtained in the foregoing manner, using slit scanning in the instrument to achieve sub-increments smaller than the detector pixel size, with a procedure to assure that there is an integral number of scanning steps across one pixel. The drift standard may be chemical analytes, or an optical interference element producing fringes related to spectral positions in each subarray. A procedure is used to identify the fringe peaks to spectral position, with temperature correction.