Spectral range:

– 0.4 – 4.7 µm (< 0.4 & > 4.7 µm: lower S/N) (4.2-4.35µm: atm. CO2 limited)

Spectral resolution: variable

– mini: < 0.1 nm (but S/N limited)
– maxi: 3.8 nm (350 – 1400 nm), 7.7 nm (600 – 2500 nm), 15.4 nm (1100 – 3600 nm), 31 nm (> 2500 nm)

Bidirectional Reflectance:

– Incidence angle: 0° to 70° (60° for bright samples) ; resolution: 2.9°; min. sampling : 0.1°
– Emergence angle: 0° to 85°; resolution : ± 2.05° (options: 0.8°, 1.25°, 1.65° but lower S/N) ; min. sampling : 0.1°
– Azimuth angle: 0° to 180° (more than half an hemisphere); resolution : ± 2.05° ; (options: 0.8°, 1.25°, 1.65° but lower S/N); min. sampling : 0.1°
– Phase angle: 5° to 160°; for bright samples: 8 to 140°

– Illumination diameter (nadir): 5.2 mm (1.8×1.43 mm with single fiber)
– Observation diameter (nadir): 20 mm

Photometry:

Absolute:
– 0.4-2.5 µm: < 1% over all configurations (relative to Spectralon© 99% reference panel)
– 2.5-4.7 µm: better than 2% over all configurations (relative to Infragold© reference panel)
Relative:
– better than 0.5% (0.4-4.7 µm)
Reproducibility: 0.1% over 24h

Polarimetry options (still under test)

Illumination :
– linear polarization : variable 0 to 90° ; spectral range : 0.3 – 2.8 µm
Observation :
– 1 component over the 0.3 – 5µm range + unpolarized or || and ┴ components over restricted spectral range

Samples:

Types: minerals, fine grained ice, organics, meteorites … (from bright to very dark)
Albedo: < 0.0003 to 1
Texture: fine to very fine grained granular or compact
Grain size: < 500 µm grain/crystal diameter; < 150 µm with a single fibre
Sample size: D > 5.7 mm (for illumination at nadir);
D > 2 mm with a single fibre
L x l > 20.5 mm x 5.7 mm (for illumination up to 75°)
Thickness:
– 0.25 mm for very dark & fine grained samples (< 25 µm)
– up to 2.5 mm for dark & medium grained samples (< 250 µm)
– up to 2.5 mm for ‘bright’ & fine grained samples (< 25 µm)

Temperature:

– room temperature or heated
– down to -10°C (in cold room)
– down to -200°C (in IceBERG environmental cell)
– up to 250°C (in Mirage environmental cell)

Experiment control:

– PC/Windows, fully software controlled (LabView©). Automatic acquisition of all spectral/geometric configurations

Acquisition time:

– single spectrum: 85 min over the 400-4700 nm range @ 10 nm sampling (431 spectral channels, 10 acquisitions per channel)
– BRDF: 24h for 32 wavelengths and 180 geometries

Current state of system:

– 0.35 – 4.8 µm range: fully calibrated
– polarization: under test (not available for external users)
– low temperature: tested in cold room down to -20°C ;
– MIRAGE thermal cell tested up to °C
– IceBERG cryogenic cell tested down to °C