horiba FluoroMax-3, Operation Manual

Page: 123 / 220

FluoroMax-3 v. 3.1 (6 Mar 2006) FluoroMax
®
-P Phosphorimeter Operation
9-3
Sample window
t
= 0
Initial
delay
Time per flash
Lamp
pulse Lamp
pulse
Parameters involved in
phosphorimetry
This sequence of excitation, delay, and sampling, is repeated for each lamp flash. The
signal is accumulated for a predetermined number of excitation pulses, then FluorEs-
sence™ collects the total signal. After collection, FluorEssence™ displays the intensity
of the luminescence as a function of time or wavelength. The
x
-axis is based on one of
the four scan options:
•
Excitation
•
Emission
•
Synchronous
•
Phosphorescence delay
Phosphorimeter parameters
Four FluorEssence™ parameters govern the sequence in a phosphorimeter experiment.
These parameters automatically appear on the phosphorimeter experiment-acquisition
dialog box.
Initial Delay
Sets the time, in ms, between the start of the lamp flash and the on-
set of data-acquisition (opening of the
Sample Window
).
Initial
Delay
can range from 0–10 000 ms, in increments of 0.001 ms.
Accuracy of
Initial Delay
is better than ± 0.001 ms.
Set
Initial Delay
long enough so that fluorescence emission and
lamp decay are complete, so that the resulting spectrum represents
phosphorescence only. The full-width at half-maximum lamp-pulse
width is 3 µs, but there is a long decay time for the light output.
Lamp intensity falls to less than 1% of peak output after 45 µs. Set-
ting the delay to > 50 µs effectively removes any interference from
the lamp.