Xylem photoLab 6600 UV-VIS - Manual (Page 59)

photoLab
®
6600 UV-VIS Operation
59 ba75848e01 08/2009
Line types The dependency between the nominal value and absorbance is often linear
in a wide range as shown in the following example:
Bild 4-2 Example of a linear calibration function after a 10-point calibration
In the case of a linear dependency, the calibration function is determined by
means of linear regression. The slope and axis intercept (E0) are the
characteristics of the calibration line.
In the case of a nonlinear dependency, the points of the measuring ranges
can be connected to each other as a polygon line or approximated as a
parabola:
Bild 4-3 Example of a polygon line calibration function after a 10-point calibration
Bild 4-4 Example of a parabola calibration function after a 10-point calibration
0
0
Nominal value (e. g. concentration)
Absorbance
0
0
Nominal value (e. g. concentration)
Absorbance
0
0
Nominal value (e. g. concentration)
Absorbance