Optical Filters; Figure 12-4: Excitation Lamp Uv Spectrum Before/After Filtration - Teledyne t100 Operation Manual

Teledyne API - T100 UV Fluorescence SO
12.1.7.

OPTICAL FILTERS

12.1.7.1. UV SOURCE OPTICAL FILTER
BEFORE
5
10
4
10
3
10
2
10
1
10
1
0
100 200
WAVELENGTH (nm)
Figure 12-4:
06807F DCN7335
Analyzer
2
•
The reference detector offset is stored as and viewable via the front panel as the test
function DRK LMP.
•
The PMT offset is stored as and viewable via the front panel as the test function
DRK PMT.
The T100 analyzer uses two stages of optical filters to enhance performance. The first
stage conditions the UV light used to excite the SO
that are not needed to produce SO
reacting to light not produced by the SO
Zinc-vapor lamps output light at other wavelengths beside the 214nm required for the
 SO
SO * transformation including a relatively bright light of the same wavelength at
2 2
which SO * fluoresces as it returns to its SO
2
intensity of light emitted by the UV lamp at 330nm is so bright, nearly five orders of
magnitude brighter than that resulting from the SO
SO * fluorescence.
2
SO *
2
Fluorescent
Spectrum
300 400
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 into SO * (refer to Figure 12-4).
2 2
*. The second stage protects the PMT detector from
2
* returning to its ground state.
2
UV SOURCE OPTICAL FILTER
5
10
4
10
3
10
2
10
1
10
1
0
500 100
Principles of Operation
by removing frequencies of light
2
ground state (330 nm). In fact, the
2
* decay, it would drown out the
2
AFTER
BANDWIDTH
SO
200 300 400
WAVELENGTH (nm)
* FLUORESCENT
2
SPECTRUM
500
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