Configurable gas analysis system

Rack 19" unit

The ARCoptix GASEX MODULAR is a fully configurable solution for gas spectroscopy applications. Besides our GASEX OEM module, the system can offer a large variety of standard components and accessories as requested by the end user application. Typical examples of accessories are heated sample lines, single board computers (SBC) for on-board processing, membrane gas pumps and so on. The GASEX MODULAR is available in a 19" rackable chassis (4U) for smooth integration in a more complex system.

The corrosion resistant gas cell can be heated up to 190 °C, which ensures that the sample remains in gaseous phase (and avoid condensation) even with high concentrations of H2O or corrosive gases. Many gases can be measured simultaneously such as CO2, H2O, CO, NH3,NO, NO2, N2O, SO2, CH4, HF, HCl, and VOC´s. Limits of detection are typically around 1ppm and absolute precision of measured concentration is around a few percent (depending also of the quality of the calibrations and measurement conditions).


  • Optimized Gas cell and FTIR Assembly
  • Rohdium Chemical resitance Coatings
  • Resolution of 2 cm-1 (1 or 0.5 cm-1 on demand)
  • MCT Detector with high detectivity TE-cooled MCT detector 5000-830 cm-1 (2-12μm)
  • 5m heated gas cell with small volume (0.2L)
  • Relatively compact (compared to other products on the market)
  • USB connectivity and SDK available
  • Cost effective

Presentation of the ARCoptix GASEX MODULAR
Optical design of the system
Interferometer coupled to a white cell

The Gasex system consist of an interferometer module including also the MCT detector and an IR light source and a Multi-reflection gas cell. The light is produced by a black body radiation module and modulated by a dual corner cube interferometer.The light is then coupled into the Gas cell (where the gas to be analysed is injected) where it is relfected back and forth 32 times. Finally the light focused on the MCT detector.

How does the interferometer 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..

GASEX MODULAR Specifications
Product code GASEX-MODULAR-RCK19

Dimensions [mm]

489 x 428 x 127 
Weight [kg] 15 (typical)
Typical accessories Single-board computer for onboard processing, Auxiliary controller board for parameters monitoring, Membrane pump, Flow-meter, Muffler/cooler (combined unit), Scrubber, Heated line
Product code GASEX-OEM-060-4TE GASEX-OEM-085-4TE GASEX-OEM-120-4TE
Beamsplitter material CaF2 ZnSe
Spectral range [cm-1] 5'000-1'660 6'600-1'200 5'000-830
Spectral range [μ m] 2.0-6.0 1.5-8.5 2.0-12.0
D* [cm Hz1/2W-1] >1x10E11 >8x10E9 >4x10E9
Signal-to-noise ratio (0.5cm-1, 1 min scan) >55'000:1 >35'000:1 >35'000:1
Detector type MCT, 4 stages thermoelectrically cooled
Interferometer design Permanently aligned with dual retro-reflector

Resolution [cm-1 ]

8,4, 2, 1 or 0.5 cm-1
Wavenumber repetability <10ppm
Scan frequency >1.5 Hz @0.5cm-1
Internal reference laser Temperature-stabilized solid-state laser @850nm


Active suppression of Water and Carbon dioxide inside the interferometer housing
A/D converter 24 bit
Operating temperature 10C - 40C
Humidity 90 % (Not condensing)
Communication interface USB 2.0
Built-in light source SiC globar stabilized at 1550 K
Power requirement (FT-IR only) <35W @ 12VDC
Software interface Windows 7/10/11, Labview, .net compatible dll, API for controlling the instrument via our DLL



Multi-pass, permanently aligned, directly mateched to the FTIR

Path lenghth [m ]


Internal volume [Litres ]


Zero gas loss

> 3 dB (less than  50 %)

Operation temperature [C]

 -20  to 200 (not condensing)
Construction Aluminium with inert coating
Parabolic mirrors

Aluminum body  with rhodium protected gold   coating 

Heaters for stabilization at 180C 

Electric 400 W  peak power, consumption in steady state:  around 30W


PID (integrated or customizable)

Operation voltage of heaters

220 V, (customizable for other voltages)

Gas  connectors

6 mm Swagelock (customizable)

ARCoptix Digital Acquisition Acquisition system: AoDAQ

The AoDAQ is a multi-threading, cross-platform and versatile software that simultaneously takes care of:

  • (1) Handling communication with the FT-IR via USB
  • (2) Processing raw signals to deliver the spectrum
  • (3) Running 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 XP, 2000 (32-bit) and Windows 7 & 8 (32 and 64 bits) 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.
  • Usual features such as save, open, zoom, rescale...
  • Some specific features related 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.


Sampling System
The sampling system can be used for measuringconcentrations of pollutants in wet, corrosive gas streams. The sample gas can be measured without drying since the sample pump, heated filter and valve are located in a module that is heated to 190 ºC. From the sampling system the gases can be directed directly into the gas cell for analysis.
Gas Cleaning

In some application, gas nedds to be cleaned before entering the gas cell with a scrubber system. The scrubber can consist of filters to remove particles, or absorber to remove water or corrosive compounds. Please contact Arcoptix to find a suitable solution for your application.


The calibration processus is highly dependend of the application. The Gasex system is not standard a fully calibrated system. The Calibriation of the system (i.e. concentration of measured gases) requires to master chemiometrics and signal evalutation as well as a deep knowledge of the aimed application. Gas calibration can be performed directely by the end-user or (dependingof the dangerosity) can be performed by Arcoptix on demand.

Non- Exclusive Distributor List for Spectrometers
France, Germany
Italy, UK
South Korea
Switzerland and
Rest of the world
Gasex Drawing
: not yet vailable
DOWNLOADPDF Quick Starter Guide
DOWNLOADPDF Drawing Gasex Gas analyser
DOWNLOAD PDF Application Note CO2 in Water
DOWNLOADPDF Application Note Isotope Measurement
DOWNLOADPDF Tutorial about Fourier Spectrometry