Patent ID: 11965823
Assignee: FOSS ANALYTICAL A/S
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 6:
7. The method according to claim 2, wherein
the mathematical transform (Icorr) is calculated as a reciprocal of an inverse intensity correction (1/Icorr) that is calculated according to equation (1),

(1/Icorr)=c1·Δ(SBZ)/+c2+(corrhum)  (1)

wherein, in equation (1),
c1 is a first empirically-determined constant that is based solely on an absorption of water relative to air at a particular nominal optical path length L0,
c2 is a second empirically-determined constant that is based on a contribution to a background due to dry air, and
(corrhum) is calculated according to equation (2),, (
          
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wherein, in equation (2),
Peak1 and Peak2 are respective intensities of an adjacent valley and peak in a fringe pattern in an infrared region of the spectral data (SBZ) from the zero material sample that is associated with a presence of humidity in the light path,
c3 is a third empirically-determined constant that is based on an influence of humidity on the mathematical transform (Icorr), and
c4 is a fourth empirically-determined constant that indicates an offset between the intensities at Peak1 and Peak2 when no humidity is present in the light path.