Bruker Daltonik GmbH
Instrument Layout
For normal operations a bias of up to 1000 volts is applied across the microchannel.
This bias current flowing through the semi-conductive layer supplies the electrons
necessary for the avalanching multiplication process.
A further performance parameter is the time response of the detector, important to
prevent deterioration of the peak resolution. Microchannel plate detectors deliver an
output voltage with a rise time (< 1ns) up to ten times faster than other detector
configurations, such as channeltrons or discrete dynode multipliers.
Each detector of the
ultraflex III
contains two MCPs coupled in series. The linear
detector is equipped with the gating option to be used to avoid saturation effects, which
may be caused by the matrix material. Please refer to the flexControl manual. Gating
is an additional feature to detect only ions of interest. All the other ions are suppressed
inclusive neutrals to avoid saturation of the linear detector.
3.1.5.6 Digitizer
Beginning with the laser shot the digitizer records the incoming analog signals from the
detectors and converts them into digital information. The digitizer card is able to attain
a sample rate up to 2 GS/sec. This assembly is incorporated in the PC. Instrument
settings on the
Detector
page in
flexControl
control the digitizer.
3.1.5.7 Laser System
The laser system operates at a repetition rate of 50 Hz maximum (200 Hz optional). It
provides the pulsed laser light to a small spot on the target. The laser system consists
of a pulsed UV laser, an attenuator that allows fine adjustment of the laser fluence, a
lens system to focus the laser beam and a mirror system to direct the beam into the ion
source on the target plate. Standard is a N2 laser with 337 nm wavelength (pulse
energy of150
µ
J) and 3 ns pulse width for use with matrix components absorbing light of
this wavelength (class IV B product). Instrument setting are performed in
flexControl
.
3.1.5.8 Camera
The camera delivers an image of the sample spot to the
Target Manipulation
Segment
of the
Graphical User Interface
.
ultraflex III User Manual, Version 1.0
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