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LAMPS vs. LIBS Technology
Current LIBS technology permits
qualitative analysis of a solid or
liquid sample by ablating a minute
portion of it, then analyzing the
resulting plasma. LAMPS takes this a
step further by employing a special
microwave cavity. The plasma is injected
into this cavity where it reacts with
free electrons, greatly increasing
sensitivity and producing better line
stability and reproducibility. A lower
power 50 mJ laser is used in the LAMPS,
resulting in less ablation imprint to the
sample and greater sensitivity.
LAMPS
Components
Spectrometers -- The key to LIBS and
LAMPS measurements is the ability to
acquire high resolution spectra over a
broad wavelength range of a transient
event. This is accomplished by coupling
7 HR2000+ spectrometers into one system.
Each spectrometer covers ~100-140 nm
typically starting at 200nm for Channel
A and ending with 980nm for Channel G.
Systems may be configured to start below
200 nm and with fewer channels for
element-specific applications. Optical
resolution is ~ 0.1nm FWHM. Pixel
resolution is ~ 0.05 nm/pixel. In a
7-channel system, there are 14,336
pixels acquiring synchronous spectra.
The detector integration time can be as
low as 1 ms, and the maximum data
transfer rate to the PC is about 500
spectra (14,336 values) per second over
the USB 2.0 port.
Sample Chamber -- Provides
critical eye safety by using laser
safety shielding and safety interlocks
on the door. The sample stage is a
manual x, y and z positioner, with
internal LED illumination for sample
positioning. A fiber bundle, inserted
inside the microwave cavity, is
constructed with a special dielectric
tip so that no metals are introduced
into the cavity.
The next release will feature a redesign
of the power supply so that it will be
housed inside the sample chamber, weigh
less, and will sustain plasmas greater
than 2 ms. CE certification is pending
the release of this next generation
power supply.
Laser
-- We provide Quantel's 50 mJ CFR Pulsed
Nd:YAG Laser with our LAMPS system. The
CFR design is especially rugged as both
resonator mirrors are on the same rigid
metal plate. The laser is mounted to the
sample chamber and aligned to the
focusing optics. A 100 mm lens with
manual z-axis control permits focusing
or allows defocusing of the laser for
better plasma uniformity.
Software – OOILIBS operating software
provides control of the lasers; has
user-programmable delay for the Q
switch; acquires, plots and saves
spectra; and provides a spectral line
library and correlation function for
identification of peaks.
Spectra can be exported to Excel.
Application-specific libraries of peaks
can be loaded. You can zoom into a
wavelength range to look for a peak in
the library by double-clicking on the
line in the table. Or, the correlation
routine will match peaks to wavelengths
in the library and rank the elements by
how many of the emission lines it found.
The user can set baseline and peak width
filters for the search.
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