SR-6500 and SR-6500A Ultra High Resolution Spectroradiometers
The SR-6500 and SR-6500A NIR spectroradiometers cover the UV/VIS/NIR range from 350-2500 nanometers. They feature ultra high resolution and very stable performance with three high density thermoelectrically cooled photodiode arrays. The SR-6500 and SR-6500A are also calibrated to NIST-traceable radiometric calibration standards.
Resolution at FWHM for the SR6500 and SR-6500A is:
- 1.5nm @ 700nm
- 3.0nm @ 1500nm
- 3.8nm @ 2100nm
Resolution is achieved using three high density solid state thermoelectrically cooled photodiode arrays:
- 1024 element TE-cooled silicon phtotodiode array detector (VIS-NIR)
- 512 element TE-cooled InGaAs photodiode array detector (SWIR 1)
- 512 element TE-cooled extended InGaAs photodiode array detector (SWIR 2)
The SR-6500 and SR-6500A feature the following Noise Equivalence Radiance (NER) performance with a 1.5 meter fiber optic:
- 0.8x10-9 W/cm2/nm/sr @ 400nm
- 0.3x10-9 W/cm2/nm/sr @ 1500nm
- 5.8x10-9 W/cm2/nm/sr @ 2100nm
NER is a measure of instrument sensitivity. Other features of the SR-6500 and SR-6500A include:
- All fixed optics – no moving parts for rugged reliability
- Auto-exposure, auto dark current shutter
- DARWin SP Data Acquisition software saves all scans as ASCII files for use with
other software programs
The SR-6500 and SR-6500A include wireless Bluetooth and USB communications and have an operating range from 0-40°C. Physical parameters include:
- Dimensions:
12.4 x 8.7 x 4.4 inches (31.5 x 22.9 x 38.7 cm)
- Weight:
11 pounds (4.99 kg)
The SR-6500A offers unmatched drift stability
Using all thermoelectrically cooled photodiode arrays, the SR-6500A spectroradiometer is built specifically for the high performance that demands unsurpassed drift stability. With the SR-6500A, you can take the spectroradiometer where it’s needed and enjoy the following features:
- Drift stability of ≤0.4% which delivers greater accuracy for long-term stability of integrating spheres
- Stability is achieved through heating and cooling thermal management features
- A temperature controller maintains the instrument housing at a stable temperature along with the individually temperature-stabilized detector arrays
- All temperatures are integrated into DARWin software readout for monitoring
The SR-6500 can be used in the field for in situ mineral, vegetation and soil identification and analysis running off a 7.4 volt 94 Watt hours lithium-ion battery that weighs around 2 pounds. One lithium-ion battery is provided and secured in the backpack with the SR-6500 for approximately 3 to 4 hours of field use.
What kind of applications will benefit from the higher resolution?
- Mineral identification and analysis where resolution can help to distinguish
between minerals with very similar spectra or to unmix and identify minerals in
trace amounts.
- Soil studies for the identification of different soil characteristics, clay types,
presence or absence of nutrients and moisture.
- Vegetation studies for plant stress/health, over-fertilization, species
identification and more.
- Lab applications such as materials identification, etc.
- Solar radiance and irradiance research.
- Microbial diversity research
The higher resolution of the SR-6500 allows you to see more features and more detail in your scans. This closeup shows the SR-6500 in blue versus a standard field spectroradiometer in green. The SR-6500 shows the additional features in the scan which can be used for more accurate mineral identification of this clay sample and better analysis of its components.
In this example, the talc sample shows an absorption feature at higher resolution with the SR-6500 (blue) that is completely missed with a high resolution standard field spectroradiometer (green).

SR-6500 can be used with a bare fiber or FOV fiber optic accessories such as the pistol grip.

The SR-6500 can be also be used with the sample contact probe or Miniprobe for identification and analysis of minerals.