Wilks InfraSpec VFA series

Variable filter spectrometers

Wilks InfraSpec VFA series is a spectral range analyzer covering a wavelength range of 2.5-4.8 µm (4000-2000 cm-1) or 5.4-10.8 µm (1850-925 cm-1), capable of measuring more than one component in your samples. e.g. biofuel.
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On-Site IR Analysis Now Easier and More Useful Than Ever Before

Wilks InfraSpec VFA series is a spectral range analyzer covering a wavelength range of 2.5-4.8 µm (4000-2000 cm-1) or 5.4-10.8 µm (1850-925 cm-1), capable of measuring more than one component in your samples. e.g. biofuel. The advantage of a filter-based spectrometer is there are no moving parts making it a compact, rugged, portable analyzer that is easy for non-technical personnel to operate on-site or in a lab – at a cost less than other analytical measurement techniques. Ideal for use at production facilities, fuel loading racks, distribution centers and regulatory testing. Comparable results to both EN 14078 and ASTM D7371 for e.g. measuring biodiesel in diesel.

The InfraSpec VFA-IR Spectrometer utilizes a patented design consisting of an ATR sample plate with a pulsable source on one end and a linear variable filter (LVF) mounted on a 128 pixel detector array on the other end.   The net result is a very compact spectrometer with no moving parts, no optical path exposed to air and capable of producing mid-infrared spectra on a variety of materials including  liquids, slurries, semi-solids and films.  A transmission variable filter array is also available for sealed cells, cuvettes, or sample cards. The InfraSpec VFA-IR Spectrometer can be used like an FT-IR Spectrometer with much of the software program geared towards repetitive process analysis applications.

An LVF can cover approximately an octave in terms of wavelength.  Examples are 2.5 - 4.8 µm (the  OH/CH region); 5.4 - 10.8 µm (the fingerprint region), or 7-14 µm.  Cubic zirconia crystals are used  for the 2.5 - 4.8 µm range, ZnS or ZnSe with the 5.4 - 10.8 µm or 7-14 µm range.



Examples – multi parameter
  • Biodiesel in diesel
  • Ethanol in gasoline
  • Total glycerides in biodiesel
  • Free fatty acid in BD feedstock
  • % trans fatty acid


A Powerful analytical Tool
  • Spectral Range Analyzer— 2.5-4.8 µm (4000-2000 cm-1), 5.4-10.8 µm (1850-925 cm-1)
  • Fast — results in less one minute  
  • Portable — 6.0 x 6.5 x 2.75 inches (15.2 x 16.5 x 7 cm),  can be battery operated
  • Affordable — less costly than most other measurement techniques
  • Lightweight — less than 4 lbs  
  • Easy to use — simplified PC interface
  • Direct readout in desired units or pass/fail
  • Data Transfer - RS-232 connections
  • Can be adapted for analyzing specific components – call us!

This product is compliant with the following test methods: