Instruction manual

7.8 Reference Information
7-47
RF-20A/20Axs
7
7.8 Reference Information
Generally, the variations of this instrument conform to "7.5 Detector Validation" P.7-7.
This section explains the following points by providing reference information on these variations.
• Wavelength calibration and the wavelength accuracy automatic checking function
• The operating procedure for wavelength calibration
^ "8.7 Performing Wavelength Calibration" P.8-39
7.8.1 Automatic Wavelength Calibration Function
In order to lighten the burden on the analyst, this instrument performs wavelength calibration automatically
when [WAVE CALIB] in the VP functions is executed.
 Wavelength Calibration
The excitation wavelength and emission wavelength are calibrated using the zero line of the low-pressure Hg
(mercury) lamp, its emission line at 254 nm, its secondary line at 507 nm and its tertiary line at 761 nm. On
executing [WAVE CALIB] in the VP functions, wavelength calibration is performed according to the flow
shown below.
Wavelength calibration is executed after [CALIBRATING SPAN] has been displayed.
After wavelength calibration has finished, the wavelength accuracy is checked automatically.
1. Detection of grating home position The spectrophotometer decides the wavelength by
taking the home position of the grating as the reference.
At the outset the home positions of the excitation
grating and emission grating are automatically
detected.
2. Movement of the excitation grating to the
region of the 254 nm position
Scan the excitation side grating in the vicinity of the low-
pressure Hg (mercury) lamp's emission line wavelength
of 254 nm, and record the peak of light intensity with the
photosensor at the excitation side.
3. Movement of the emission grating to the
0nm position
The excitation grating is moved to the 254 nm position
found in step 2.
Next, scan the emission side grating in the vicinity of
0 nm, and record the peak of light intensity with the
photosensor at the emission side.