horiba FluoroMax-3, Operation Manual

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FluoroMax-3 v. 3.1 (6 Mar 2006) Glossary
13-3
filenames and
XCORRECT
.
SPC
and
MCORRECT
.
SPC
, respectively.
CTI card
This acquisition and control card, located in the rear of the Fluoro-
Max
®
-3, is the counter-timer-integrator board. It handles all spectro-
fluorometer control, timing, and data acquisition for measurements
on the system. The boards carry by default two acquisition channels,
and are linked to all monochromator and accessory control boards on
the underside of the instrument. The CTI card fits into a slot in the
motherboard on the rear of the FluoroMax
®
-3.
Current input module
(DM303)
The current input module collects the current signal from the refer-
ence photodiode, digitizes the data, and sends it to the CTI card for
data-processing. This module is located directly behind the reference
photodiode. It has linear response from 0–10
μ
A.
Dark counts
Inherent background signal measured in counts s
–1
(cps) observed on
the photomultiplier tube when high voltage is applied. Typically, the
R928P photomultiplier tube used for the FluoroMax
®
-3 system has
dark counts of < 1000 cps.
Dark offset
The software correction used to subtract dark counts (or dark signal)
on a detector from a spectral acquisition. This option appears as a
checkbox in the FluorEssence™ software. Use a corrected signal
channel for the acquisition (e.g.,
S
) in order to run the
Dark Offset
correction.
Datafile
A file used to store spectral data, constant-wavelength analysis data,
or other recorded data. In FluorEssence™, the most common datafile
is the spectral file (
.SPC
). This is the file-type that contains spectra
acquired from a scan run from the
Experiment Setup
menu (e.g.,
emission scan, time-base scan, single-point, etc.). Datafiles contain
all of the information regarding the instrument setup for a scan as
well as the spectra (see more information in the
FluorEssence™
User’s Guide and the on-line help files). Multifiles are three-
dimensional datafiles that contain an array of spectral files.
Dispersion
The range of wavelengths of light across the field of view of the en-
trance and exit apertures. Dispersion depends on the focal length of
the monochromator, the groove density of the optics, and the
f -
number (speed) of the monochromator. Dispersion is usually ex-
pressed in nanometers of spectral coverage per millimeters of slit
width (nm/mm).
Emission monochromator
The monochromator located after the sample compartment used to
isolate discrete wavelength components of the sample’s fluorescence,
and may be used to scan the emission from a sample. The emission
monochromator on the FluoroMax
®
-3 is an 0.18-m single mono-
chromator with a Czerny-Turner design: the monochromator includes
a collimating mirror, the reflection grating (blazed at 500 nm), and a
focusing mirror, with slit apertures at the entrance and exit. The
emission-photomultiplier detector is connected to the exit of this