Compact and Robust Gas Analysis Module

Powerful module for gas analysis, based on our robust and approved "Rocket" FTIR with 4 wave-numbers resolution, and an ultra-compact 5 meters optical path, low volume ( 0.2 Liter) multi-pass heated cell. GASEX is, to our knowledge, the most compact gas analyzer module on the market, optimized for your applications.

The ARCoptix Gasex modules is the ideal product for system integrators looking for a customized and intergrable system. The Gasex system contains essentially 4 components:

  • Optimized Gas cell and FTIR Assembly
  • Compact and rugged
  • Resolution of 2 cm-1 down to 0.5 cm-1
  • MCT Detector with high detectivity TE-cooled MCT detector 5000-830 cm-1 (2-12μm)
  • 5m heated gas cell with small volume (0.2L)
  • USB connectivity and SDK available
  • Cost effective

  • Below some examples of Spectra Measured with the Gasex system 0.5 cm-1 resolution:












    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 solidary to a common swinging arm, which rotates to create an optical path difference in the two arms of the interferometer.
    This type of design is called a permanently aligned interferometer, as the alignment of the system 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 Specifications


    Permanentely aligned, maintenance free, hermetic

    Resolution [cm-1 ]

    2, 1 or 0.5 cm-1

    Spectral range [cm-1 ]

    830 - 5000

    Beam-splitter/ windows


    Wavenumber repetability

    Scan frequency 2 - 4 spectrum / second
    (resolution dependent)
    Control laser

    solid-state laser @850nm


    MCT,Thermoelectrically cooled;
    D*=2.5e9 Jones

    Signal to Noise ratio (0.5 cm-1, 1 minute scan)



    Position independent


    Active suppression of Water and Carbon dioxide inside the interferometer housing
    A/D converter 24 bit
    Operating temperature 10C - 40C


    90 % (Not condensing)
    Communication interface USB 2.0
    Radiation source Glo-bar stabilized at 1550 K
    Power requirement 12V / 8W (excluding IR source) 30 W together with the glo-bar
    Software interface

    7/10, Labview, .net compatible dll
    API for controlling the instrument via our DLL

    Dimensions 180mm x 160mm x 80mm
    Weight 1800 g



    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)


    Dimensions [mm]

    380 x 180 x 120 
    Total weight [kg] 3.8
    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 180 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. The integration of the FTIR gas analyser is generally done by our customer that has a better understanding of the end-user applications. On request Arcoptix can support the customers with this tasks.

    Non-exclusive Distributor list for spectrometers:
    For OEM Business: contact Arcoptix directly. FTIR OEM Business
    France, Germany
    Italy, UK

    Russia, Moscow FTIR Russia

    South Korea
    Switzerland and
    Rest of the world
    Gasex Drawing

    Gas Analyzer Dimension in mm:

    DOWNLOADPDF Description of Gasex Gas analyser
    DOWNLOADPDF Quick Starter Guide
    DOWNLOADPDF Drawing Gasex Gas analyser
    DOWNLOAD PDF Application Note CO2 in Water
    DOWNLOADPDF Application Note NH3 in Water
    DOWNLOADPDF Application Note Isotope Measurement
    DOWNLOADPDF Tutorial about Fourier Spectrometry