User guide

6200T Total Sulfur Analyzer Principles of Operation
Teledyen Analytical Instruments 291
LAMP OUTPUT
(Arbitrary Untis)
10
5
10
4
10
2
202.5
307.6
481.1
10
3
10
1
1
100 200 300 400 500
WAVELENGTH (nm)
0
213.9
330.3
275.6
SO
2
*
Fluorescent
Spectrum
LAMP OUTPUT
(Arbitrary Untis)
10
5
10
4
10
2
10
3
10
1
1
100 200 300 400 500
WAVELENGTH (nm)
0
213.9
330.3
SO
2
* FLUORESCENT
SPECTRUM
UV SOURCE OPTICAL FILTER
BANDWIDTH
BEFORE AFTER
Figure 13-4: Excitation Lamp UV Spectrum Before/After Filtration
To solve this problem, the light emitted by the excitation UV lamp passes through a
band pass filter that screens out photons with wavelengths outside the spectrum required
to excite SO
2
into SO
2
* (refer to
Figure 13-4).