HunterLab SpectraTrend HT, Руководство пользователя

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SpectraTrend HT User’s Guide 3.2
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OPERATION
Standardization Using the Front Panel Display
STANDARDIZATION sets the top and bottom of scale for the neutral axis. During
standardization, the BOTTOM-OF-SCALE (zero) is set first. For this, you simulate the case where
the source light is absorbed by the sample. This is done by sliding the black glass that is
contained in the calibration box in to place. The
TOP-OF-SCALE is then set by scaling the light
which is reflected from the calibrated white tile also in the calibration box. Messages on the
LCD screen prompt you through the standardization process as described below. The time
elapsed (in hours/days) since the last standardization is shown in the upper right corner of the
screen.
It is extremely important that the standard used for standardization be treated carefully. It
must be clean and in good condition if standardization is to be successful. If there is any doubt
about the standard being clean, clean it as described in the
MAINTENANCE AND
TROUBLESHOOTING chapter.
Standardization, when the system is referenced to a reading of the white tile in the slide-on
calibrator is performed as follows:
•
Check that the tiles are clean and free of dust and scratches. If they are dirty
(including marked with
fingerprints), clean them as described in “Maintaining and
Testing SpectraTrend HT .”
•
Select Standardize from the SpectraTrend HT’s main menu by moving the cursor
highlight to its position using the up and down arrow buttons and then pressing the
(Go) button.
•
Confirm the white tile values and green tile values by comparing to the values on the
calibration box.
Figure 73. Confirming the Values of the White and Green Tiles
•
The STANDARDIZATION screen appears, prompting you to place the black glass.