Thermo Scientific Vanquish VH-D10 Operating Manual page 97

Diode Array Detectors (VH-D10)
Operating Manual
Parameters Description
Wavelength Set a wavelength for each UV_VIS_x signal channel individually,
in the range of 190 nm to 680 nm for up to 10 signal channels.
The wavelength defines the value at which the device measures
the absorbance of the analyte(s) in the sample. Observe the
following:
• Set the Wavelength to the wavelength with the absorbance
maxima for the analytes of interest.
• For best selectivity, select a specific wavelength for every
substance to be analyzed with a low optical bandwidth, for
example, by using a separate signal channel for each analyte.
• To obtain optimum linearity, set the Wavelength to a peak or a
valley in the absorption spectrum. A valley can provide best
linearity for high concentrations.
Data collection The data collection rate is the number of data points per second
rate (Hz) that Chromeleon collects from the device and stores as raw
data. Select a data collection rate up to 200 Hz.
Set the data collection rate, at which data is to be collected from
the device. The data collection rate applies for all signal channels
and the 3D field.
As a standard, when setting the Data Collection Rate parameter,
the response time and peak width are defined.
For guidelines on selecting the data collection rate, see
the Data Collection Rate
Bandwidth The bandwidth specifies the optical bandwidth (i.e. the ability of
the device to distinguish between single wavelengths), at which
the signal channel (UV_VIS) is recorded. In general, this
corresponds to the optical resolution of a device.
The standard Bandwidth is set to 4 nm. If required, you can set a
different value for the bandwidth.
For details on the bandwidth and setting it to a different value,
see Optimizing the Bandwidth and Slit Width Settings
(} page 102).
Slit width The slit width determines how much light passes through the
adjustable entrance slit and is available for measurement. As
more light is available for the measurement, the baseline noise is
minimized. However, the optical resolution diminishes.
The setting of the slit width affects all signal channels and the 3D
field.
The standard Slit Width is set to 4 nm. If required, you can set a
different value for the slit width.
For details on the slit width and selecting it individually, see
Optimizing the Bandwidth and Slit Width Settings
Response time The response time determines how quickly the device responds
to a change in signal.
As a standard, the Response Time setting is defined when the
data collection rate is set. If required, you can set a specific value
for the response time.
For details on the response time and selecting it individually, see
Selecting the Response Time and Peak Width
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Operation
Selecting
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