The Near-infrared region is usually defined as the range of wavelengths from 750 nm to 2500nm. Starna has developed reference materials specifically designed for absorbance qualification in this region.

Metal-on-Quartz Neutral Density Filters (250 - 3200 nm)

This Reference Material can be used to qualify the Absorbance scale, in the ultra-violet, visible and near-infrared regions of the spectrum (250 nm to 3200 nm) of spectrophotometers with spectral bandwidths not exceeding 6.5 nm.  Absorbance and Transmittance values are certified at 250.0, 360.0, 465.0, 546.1, 635, 1100, 1700, 2210, 2500, and  2850 nm. Before purchase, users should check that these filters are 
compatible with their spectrophotometer - see data sheet.

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NIR Neutral Density Filters (800 nm to 3200 nm) 

This Reference Material is specially designed for the wavelength qualification of near-infrared reflectance spectrophotometers over the range 900 nm to 2600 nm. These references can be used to qualify the absorbance accuracy and linearity of near-infrared spectrophotometers with a spectral bandwidth of 6.5 nm or less, over the wavelength range 800 nm - 3200 nm. Calibration values (in % Transmission and Absorbance) are certified at 1100, 1700, 2210, 2500 and 2850 nm.

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