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Non-Dispersive Infrared / NDIR

The story of nondispersive IR spectroscopy (NDIR) gas analysis began back in 1943.

Today, over 100 different gases can be detected reliably from the ppm to the percent range. This method of analysis is used, in particular, in medicine to analyze respiratory gas, in the automobile industry to analyze emissions, and in chemical applications.

The gas to be analyzed is commonly channeled into a sealed room and exposed to an IR pulse source. As soon as the gas absorbs the IR radiation, the attenuation can be detected using a suitable detector. The concentration of the gas can then be determined based on the attenuation.

Gas analysis can be carried out with multispectral pyroelectric infrared detectors. These sensors combine several single-channel detectors in a single housing and are equipped with different filters. This setup allows the individual detectors to detect different gases. Currently, it is possible to carry out up to four measurements with a single detector. Multispectral pyrodetectors make it possible to design very compact gas analyzers.

NDIR is by far the most commonly used gas detection method today due to its simplicity.

Gas is passed through a measurement cell where a broadband IR source is used to emit light through the cell to a detector. The detector uses IR optical filters to filter the light into an “active channel” at the absorption wavelength of the target gas and a reference channel.

Used for CO2 detection. One of the most common gases that is detected via this method is CO2 at approx. 4.3 μm. The advantage of NDIR comes from the strength of absorption in the mid IR compared to methods in the near IR. This strong absorption allows relatively low concentrations of gas to be detected with small path lengths and inexpensive components.

Products. LASER COMPONENTS can provide detectors that have more than one channel with many filter options, one channel as a reference and the others for the gases you would like to detect. We also offer a filter that enables infrared humidity measurements in many applications.

Challenges. NDIR is also not without its challenges: selection of the correct filters to minimize crosstalk combined with the angular and temperature dependence of these filters can cause undesired results. LASER COMPONENTS has years of experience in this field, and our standard selection of filters has been carefully chosen to help you easily find the best filters for your application.

The selection of the right IR Detector is key to get reliable measurement results.

Let's get in touch!
Tim Huylebrouck
Head of Business Unit Infrared
Tim Huylebrouck
LASER COMPONENTS Germany GmbH
82140 Olching

Product Selection

Made for TLDS Equipment

LASER COMPONENTS SUPPLIES DETECTORS, OPTICS AND LASERS TO NDIR users.
L2411D2020-HCEK L2411D2020-HCEK
IR detectors have been a part of our standard product range at LASER COMPONENTS for almost three decades. A distinction is made between sensors for the near infrared range (NIR) from 1.0 µm to 2.5 µm and those for the mid-infrared range (MIR) above 2.5 µm. IR detectors of all modes of operation are a part of our product portfolio and leave nothing to be desired.
HIS2000R-0WC IR Emitter HIS2000R-0WC IR Emitter
Continuous-wave and pulsable IR emitters are available, both of which are based on metal alloys.
IR Filter IR Filter
A wide variety of interference filters in the IR range is available: Bandpass filters, long-pass filters, short-pass filters, blocking filters, and dichroic splitters are included in this range of products.
Team of experts
You have questions or need our support?
Please call us.
Uwe Asmus
Sales Account Manager / IR Components and Optical Filters
Uwe Asmus
LASER COMPONENTS Germany GmbH
82140 Olching
Pierre Chazan
Senior Business Development Manager
Pierre Chazan
LASER COMPONENTS S.A.S.
92190 Meudon
Harvey Washbrook
Sales Account Manager
Harvey Washbrook
Laser Components Nordic AB
41263 Göteborg - Sweden
Edward Williams
Technical Sales Engineer
Edward Williams
LASER COMPONENTS (UK) Ltd.
CM2 7PR Chelmsford Essex
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Laser Components

Werner-von-Siemens-Str. 15
82140 Olching
Deutschland

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