Diffuse Reflectance

Near–IR has been used for the analysis of agricultural products and other scattering solids for many decades. In the past, most applications have involved either loading the product onto a specialized sampling stage or the use of probes based on large diameter fiber–optic bundles. In contrast, Hellma Axiom’s diffuse reflectance probes are designed to be used with small diameter bundles or even single fibers. This provides greater flexibility, much lower transmission cost, and optimum coupling to the newer generations of spectrometers such as those employing charged–coupled detector arrays, FT–NIR, and tunable laser diodes. For further discussions of diffuse reflectance analysis, see Technical Notes AN-9114, AN-9165, and AN-9226.


Immersion Probes

The FDR-700 Series Diffuse Reflectance Probes provide for the spectroscopic analysis of optically scattering materials such as pharmaceutical powders, polymers, and food products. Key characteristics of these probes are high collection efficiency, low stray light, robust construction, and excellent chemical resistance.

FDR–700 Series Features

  • Compatible with high temperatures and pressures
  • Suitable for use with most chemicals
  • High collection efficiency
  • Low stray light
  • Compatible with most Near-IR and UV-Visible spectrometers
  • Available with long fiber-optic cables for remote operation
  • Compact retractable version available (FDR-798)

FDR-700 Data Sheet (.pdf)


Non-Contact Probes

FDR-800 Series diffuse reflectance probes have been designed to provide optimum performance in the non-contact analysis of powders and other diffusely reflecting materials. These probes are characterized by high collection efficiencies, large depths of field, and low stray light.

FDR–800 Series Features

  • Target offsets from 7 to 120 mm
  • Adjustable offset and collection area
  • Very low stray light
  • Optimized sensitivity
  • Self-cleaning capability (FDR-825)

FDR-800 Data Sheet (.pdf)