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Device Overview
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Fluorescence Detectors (VC-D50, VC-D51, VF-D50, VF-D51)
Operating Manual
Fluorescence is used, for example, in highlighters or in whitening agents
(optical brighteners). Fluorescent paint used in highlighters absorbs in
the blue and near, non-visible ultraviolet range of the daylight and emits
light at a longer wavelength (typically blue-green, yellow and red).
As shown in the following figure, the light beam from the xenon flash
lamp (no. 1) is focused by the lamp optics (no. 2) through the entrance
of the excitation monochromator (no. 3). The excitation monochromator
transmits only light of the user-selected wavelength to the sample inside
the flow cell (no. 4). Most of the light penetrates the sample, stimulating
the sample to emit fluorescence light. A reference sensor (no. 5) behind
the flow cell measures the intensity of the excitation light. The reference
signal is used to compensate fluctuations in lamp intensity and thus
improve sensitivity.
Upon exiting the flow cell, the emitted light is focused by the emission
optics (no. 6) through the emission monochromator (no. 8).
A cut-off filter, which lets only light above a certain wavelength pass, is
located before the emission monochromator. VF detectors have a filter
wheel (no. 7) installed, which can be moved to 5 different positions with
different cut-off wavelengths with the help of a motor. The selectable
filter helps to achieve an even better sensitivity and increases flexibility
during method development. With VC detectors, the filter has a fixed
cut-off wavelength of 280 nm.
The emission monochromator transmits only the light with the user-
selected emission wavelength to a photomultiplier tube (PMT) (no. 9),
where the light intensity is measured. A second (optional) red-sensitive
photomultiplier tube (no. 10) measures light in the near-infrared region
(up to 900 nm).
Содержание Vanquish VC-D50
Страница 4: ...Contacting Us Page 4 Fluorescence Detectors VC D50 VC D51 VF D50 VF D51 Operating Manual...
Страница 10: ...Contents Page 10 Fluorescence Detectors VC D50 VC D51 VF D50 VF D51 Operating Manual...
Страница 30: ...2 Safety Page 30 Fluorescence Detectors VC D50 VC D51 VF D50 VF D51 Operating Manual...
Страница 42: ...3 Device Overview Page 42 Fluorescence Detectors VC D50 VC D51 VF D50 VF D51 Operating Manual...
Страница 88: ...5 Installation Page 88 Fluorescence Detectors VC D50 VC D51 VF D50 VF D51 Operating Manual...
Страница 122: ...6 Operation Page 122 Fluorescence Detectors VC D50 VC D51 VF D50 VF D51 Operating Manual...
Страница 154: ...7 Maintenance and Service Page 154 Fluorescence Detectors VC D50 VC D51 VF D50 VF D51 Operating Manual...
Страница 170: ...9 Specifications Page 170 Fluorescence Detectors VC D50 VC D51 VF D50 VF D51 Operating Manual...
Страница 187: ...Index Fluorescence Detectors VC D50 VC D51 VF D50 VF D51 Operating Manual Page 187...
Страница 188: ...Thermo Fisher Scientific Inc 168 Third Avenue Waltham Massachusetts 02451 USA www thermofisher com...