Laser Spectrometer
Customized IR Laser Systems

Laser spectroscopy can be an interesting alternative to FTIR spectroscopy. In particular if only one or two component needs to be measured with a low detection limit (below a fraction of ppm) is needed. Arcoptix is specialized in the realisation and fabrication of laser spectrometer systems that permits to address such high demanding appliations. Often the systems needs to be customized to specific applications. Contact one of our IR Laser experts for more information.

ARCoptix is capable to make a full working customized product based on IR Lasers produced by our partners (as shown in the picture).

Systems mostely consit of 1-3 IR lasers that are tuned exactely on the absorption lines of the components that need to be measured, infrared detectors, optics (mirrors, leses, fiber,..), Control electronics and software. Depnding of the application the system can be combined with other type of detectors like FTIR, electrochemical,..

 

   
Advantages of a spectroscopic Laser system: Limitations of a spectroscopic laser system:
  • High sensitivity, low detection limit (ppb)
  • Remote measurement (hunderds meters of space)
  • Mesurement speed (thousends of mesurements per sec.)
  • High selectivity (No interference with other substancies)
  • Compact and robust solutions (portable solutions)
  • Limited to only a very few components 1 or 2. In case neeeds to be combined with other technologies.
  • limited to narrow wavelength ranges
  • No universal solution (dedicated lasers required).
  • LASER spectroscopy Principle

    Infrared spectroscopy exploits the fact that molecules absorb IR light frequencies that are characteristic of their chemical structure. These absorption frequencies depends of the specific vibrationnal modes of the molecules. So every molecule presents a different IR abosrption spectrum and can be considered as a kind of finger print.
    Just like any spectrometer, a laser spectrometer is following the same basic principle. Light emitted from a coherent source is interacting in some way with the analyzed sample(solide, liquid or gas). The Light is then detected by a special infrared detector (MCT, DGTS). The detected intensity is evaluated by a dedicated software and the concentration of the analyzed substances (mostely gases but can also be liquids or solid) are calucluated.


    How does IR LASERs work?

    IR lasers are often so-called QCL lasers (Quantum cascade lasers).For the past 20 years a great achivement have been in this field. QCL Lasers that covers a very wide field of wavelength ranges going from 800cm-1 to 200cm-1 are now available. Lasers can also be tuned over a limited wavelength range (typically 100- 200 cm-1) if this is required by the application. The shema on the left shows an example of an emission spectrum of a single mode tuneable laser emitting in the mid- infrared band.

    QCL LASERs

    QCL lasers are special (mutiple quantum wells) solid state diode lasers. The detailed description of QCL lasers is relatively complex a detailed explanation can be found on wipikedia.

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