Thermo Finnigan SpectraSYSTEM UV6000LP, Справочное руководство

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January 2004 Thermo Electron 5-17
THE CALIBRATION
PAGE
Array Group
One of the two functions of the Calibration page (Figure 5.10) is to
measure and correct for dark current produced by the photodiode
array. Even when both lamps are turned off, the array still produces a
small amount of background signal that is referred to as dark current.
Typical dark current values range from 1,500 - 3,000 counts.
Before intensity values can be converted to absorbance units, the dark
current must be subtracted from the intensity measurements.
Following dark current calibration, light intensity values will be
automatically corrected for dark current. Remember that both lamps
must be turned on during calibration.
NOTE: Neither calibration program will run when data collection is
enabled on the Display page.
HINT: Be sure to check light intensities before performing the dark current
or wavelength calibration procedures to ensure that the array is not
saturated. Refer to the Operation Verification section on page 4-6.
Figure 5.10 The Calibration Page