Fibered NIR spectrometer with a spectral range from 900 to 2500 nm
If you are looking for a high performance, compact and affordable NIR spectrometer, the ARCoptix
FT-NIR Rocket is the instrument that you need. Thanks to its permanently aligned interferometer
and
solid-state reference laser, the FT-NIR Rocket offers excellent stability in both intensity and
wavelength scales. The FT-NIR Rocket is compatible with light sources and sampling accessories
(like
fibers, cuvette folder, ...) typically used with array-detector based NIR spectrometers.
The FT-NIR Rocket is a high-performance system combining high resolution, broad wavelength range
and excellent sensitivity. The FT-NIR functioning principle permits to measure over a much broader
range than grating spectrometers that are limited to 2100nm.
Its outstanding stability in both wavelength and intensity scales makes it an ideal tool for
highly reproducible chemometric
analysis.In comparison to array-photodiode NIR spectrometers, the single photodiode operation of the
FT-NIR ensures no defect pixels, no gain variation among pixels and no dark-current drifts.
Also, the device does not suffer from stray-light as grating spectrometers.
Example of application using the
ARCoptix FT-NIR spectrometer with the ARCoptix ARCSPHERE (diffuse reflection accessory)
Characteristics
Wide wavelength range 0.9-2.5 µm
High resolution 2cm-1
(equivalent to <0.25nm@1um and <1.25nm@2.5um)
Excellent stability in intensity & wavelength scale
(no dark current-induced drift, internal reference laser)
Very good sensitivity (2TE cooled InGaAs)
Compact and rugger, easy-to-use fiber input system
Cost effective (single NIR photodiode)
How does it work?
Permanentely aligned interferometer
The heart of the FT-Rocket is dual corner-cube (retro-reflector) interferometer. The
two corner-cubes are fixed to a common swinging arm, which rotates to create an optical path
difference (with respect to the beam splitter) in the two arms of the interferometer.
This type of design is called a permanently aligned interferometer. This particular
arrangement of the interfeormeter is known to be the most robust against vibrations and temperature
drifts. It never has to be realigned. The swinging arm of the interferometer rotates on wear-free
flexure system, making
this mechanical system extremely robust and durable.
Solid-state reference laser
For measuring the movement of the mirrors, a solid-state reference laser is coupled into the
interferometer. Compared to classic HeNe lasers, the solid-state lasers that we use are more compact
and have a much longer life-time. They have a very low temperature-induced wavelegnth drift and, when
kept at constant temperature with a Peltier element, their wavelength can be stabilized to a few PPM,
thus providing a very accurate and reproducible wavelength scale. This is crucial for ensuring a
day-to-day and unit-to-unit consistency..
Windows 7, 10 & 11
API for controlling the instrument via our DLL
Dimensions
180mm x 160mm x 80mm
Weight
1700g
Frequently Asked Questions
What is the resolution of the FT-NIR Rocket in
nm (wavelengths)?
The resolution of Fourier-transform spectrometers is usually expressed in wave-numbers (ν), which
are simply the inverse of wavelength (ν=1/λ). The conversion betwen wave-number resolution
and wavelength resolution is Δλ = λ2 · Δν. The the
graph below shows this conversion for the situations where Δν = 2cm-1,
4cm-1 or 8cm-1.
Can I use the FT-NIR Rocket with standard
fiber-optics accessories?
Yes. Although the ARCoptix FT-NIR is not a dispersive but a Fourier-transform spectrometer, accessories
normally used with dispersive spectrometer are compatible. The spectrometer has a SMA-905 input fiber
connector. One just has to take care that accessories are NIR compatible. For example, optical fibers
must be rated "low-OH content" to avoid too high absorption in the NIR.
What is the temperature-stabilized internal
reference laser?
The precision of the wavelength scale in Fourier-transform spectrometers relies on its internal
reference laser.
In our compact FT spectrometers, the reference laser is a solid-state type whose central wavelength has
a naturally low temperature-induced drift, ~70 ppm/ºC.
In some applications, this is sufficient. But in other applications, a more reproducible wavelength
scale must be achieved by the spectrometer.
With the temperature-stabilization of the laser (via a thermoelectric element) a wavelength
reproducibility < 10 ppm can be guaranteed all over the instrument operational temperature range
(5-40 ºC). To give an example, at 1000nm wavelength, a shift of 10 ppm means 10E-6 * 1000nm =
0.01nm. This is especially important for applications such as laser characterization or chemometric
analysis.
ARCoptix Digital Acquisition
Acquisition system: AoDAQ
The AoDAQ is a multi-threading, cross-platform and versatile software that simultaneously takes care
of:
1Handling communication with the FT-IR via USB
2Processing raw signals to deliver the spectrum
3Running a TCP ethernet server
The AoDAQ can be installed on all sorts of computers, from desktop machines to embedded, low-power
single board computers. Thanks to the hosting of a TCP server, the instrument data and parameters can
be accessed locally and/or remotely. All communication with the instrument eventually reduces to a set
of TCP/IP commands that allow to quickly acquire data, adjust parameters, monitor the instrument
status etc. using the programming environment of your choice.
Free GUI basic software
The FTIR Rocket is delivered with a free Windows 7 & Windows 10 compatible graphical user
interface (GUI) program.
The free basic software package allows the user to:
Configure hardware measurement parameters (amplifier gain, averaging, ...).
Display real-time spectral measurement results.
Set reference spectra (white, dark) and choose among raw spectra, transmission or reflection mode.
Perform usual operations such as save, open, zoom, rescale...
Select features specific to Fourier transform spectrometry: choose among spectrum or interferogram
averaging, apodization,
look and save the interferograms, etc.
Free API & Examples
The FTIR Rocket is also delivered with a free API that allows you to control the spectrometer with
custom code via our DLLs. Examples are available for the following languages:
C++
C#
Labview
Matlab
Advanced data processing & analysis
software
In collaboration with Labcognition
GmbH in Germany we also
offer additional Panorama software packages:
Math Add-on module
contains a set of standard manipulation operations used in spectroscopy, like normalization,
derivative, baseline correction, peak picking and more.
In addition some special operations are available, like multiplicative scatter correction,
thickness
correction or standard normal variate
correction and others.
Quantity Add-on module
is an expert in multivariate data analysis with quantitative methods like PLS and MLR. A
convenient
and intuitive wizard guides you through all
steps of calibration model development. Complex statistical methods become very easy to use even
for
non-experienced users.
Search Add-on module
is an ideal add-on to archive your spectroscopic data and related information. It includes
spectrum
and full text search functionality on spectral libraries of various different library formats or
directly on data in the file system.
IRAnalyze software package
is a highly sophisticated IR spectrum interpretation tool. Based on an IR spectrum, it provides
you
with automatic results for IR bands
to functional group correlations and their characteristic frequencies. Furthermore, it is a
comprehensive electronic dictionary to browse
frequiencies for correlated IR bands.
Accessories
Transmission measurement
The sketch below shows a typical configuration for using the FT-NIR Rocket for transmission
measurements. In addition to the spectrometer, you will need one NIR light source, a cuvette/sample
holder and 2 NIR optical fibers.
ArcLight NIR lamps
The ARCoptix ArcLight NIR is the version of our lamp optimized for the VIS-NIR (400 –
4,000nm) spectral range. It uses a high temperature (>2850 K), 20W QTH bulb. The lamp has a
removable fiber coupler SMA-905 connector that allows switching between free-space and fibered
optics.
The CUV-NIR is a cuvette holder ideal for the visible to near-infrared (0.4-2.6 microns). It
comes with 2 fiber collimators / fiber couplers with SMA-905 connectors. The sample slot is
12.5mm
wide, thus accepting glass cuvettes with an optical path of up to 10mm. The CUV-NIR has an
additional slot to hold a filter, e.g to reduce heating of the sample and shot noise due to
light
out of the spectral range of interest.
Diffuse reflection measurement
Another typical measurement configuration is diffuse reflectance. There are several possible
configurations, among which a very good one is to use our internally illuminated integrating sphere,
as shown in the video below.
Integrating sphere with internal light
source (ArcSphere-50-Hal)
The ArcSphere-50-Hal is an integrating
sphere with internal halogen light source for
diffuse reflection VIS/NIR measurements.
The ArcSphere-50-Hal has an internal
diameter of 50mm, a sample port diameter of 10mm,
and an SMA-905 fiber connector to connect to
the spectrometer.
The internally illuminated integrating sphere
provides a much stronger signal than
spheres illuminated via fiber optic coupled.
