Thermo Scientific Surveyor UV Plus, Руководство по оборудованию

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1
Introduction
Functional Description
2 Surveyor UV/Vis Plus Detector Hardware Manual Thermo Scientific
Functional Description
The Surveyor UV/Vis Plus Detector is a full-featured, time-programmable,
variable-wavelength UV/Vis (ultraviolet/visible) absorbance detector. It operates in either the
single or dual wavelength mode in the UV or visible ranges.
The UV/Vis detector is a benchtop unit for inclusion into the Surveyor Plus LC System. You
control the detector remotely over an Ethernet communications link from a Thermo
Scientific data system computer.
The UV/Vis detector consists of a dual light source, an optical bench (see Figure 2 ), dual
photodiode detectors, and several printed circuit boards (PCBs).
Figure 2. Surveyor UV/Vis Plus Detector optical bench
To provide a complete spectrum of ultraviolet (UV) and visible light, the detector uses a
deuterium lamp (D2) for the UV range (190 to 365 nm) and a tungsten lamp (W) for the
visible range (366 to 800 nm). The lamp cover has a safety interlock that reduces the
possibility of human exposure to harmful UV light. When you remove the cover, the lamps
automatically turn off. A computer-controlled shutter selects the deuterium lamp for sample
analyses in the UV range and the tungsten lamp for sample analyses in the visible range. The
light from the selected lamp goes to a holographic grating that disperses the light into a
spectrum. The grating turns to select the programmed wavelength. For precise wavelength
control, a stepper motor controls the alignment of the grating. A system of baffles that reduces
stray light in the optical bench increases the absorbance linearity.
Tungsten
lamp
Deuterium
lamp
Sample
photodiode
Reference
photodiode
Lens
Flow cell
Beamsplitter
Shutter
Grating