Technical characteristics

**Spectral range:

– 0.45 – 4.5 µm (< 0.45 & > 4.5 µm: lower S/N) (4.2-4.35µm: atm. CO2 limited)

**Spectral resolution: variable

– mini: < 0.1 nm (but S/N limited)
– maxi: 2.2 nm (<600nm), 9.5 nm (<1430nm), 19 nm (<3200nm), 39nm (>3000nm)

**Bidirectional Reflectance:

– Incidence angle: 0° to 85° ; resolution: 0.1° ; maximum sampling : 0.1°
– Emergence angle: 0° to 80° (to 83° for dark / fine grained samples) ; resolution : ± 2.05° (may be reduced to < ± 0.5°, but S/N limited) ; max. sampling : 0.1°
– Azimuth angle: 0° to 180° ; resolution : ± 2.05° (may be reduced to < ± 0.5°, but S/N limited) ; max. sampling : 0.1°
– Phase angle: mini to 165° ; mini : 8° for bright / large grained samples ; 4° for dark / fine grained samples

– Illumination diameter (nadir): 200 mm
– Observation diameter (nadir): 20 mm

**Small samples option

For samples smaller than 25 mm in diameter we also have a special attachment that change both the illumination diameter and solid angle as for SHADOWS:

– Illumination diameter (nadir): 7.5 mm
– Incidence angle: 0° to 65° (55° for bright samples) ; resolution: ±2.9°; min. sampling : 0.1°
– Emergence angle: 0° to 85°; resolution : ± 2°

**Photometry:

Absolute:
– 0.4-1.0 µm: better than 1% over all configurations (relative to a calibrated Spectralon 0.99 reference panel)
– 1.0-2.5 µm: better than 1% over all configurations
– 2.5-5 µm : better than 2% over all configurations
Relative :
– better than 0.5% (0.4-2.5 µm)

**Polarimetry options (only partly tested, not available for TNA)

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: rocks, minerals, snow / ice, sulfur, … (from very bright to moderately dark)
Albedo: 0.1 to 1
Texture: compact or granular
Grain size: micrometer to a few millimeters
Size:
maxi:
– 300mm diameter, 250 mm deep (for bright & coarse grained samples)
– 120 mm in diameter, 2-10 mm deep (for dark or fine grained samples)
mini:
– 25 mm x 120 mm (for principal plane observation down to 80°)
– 25 mm x 45 mm (for principal plane observation down to 60°)

**Temperature:

– room temperature or heated
– down to -20°C (in cold room)
– up to 80°C and down to -40°C (in SERAC environmental cell)
– down to -208°C (in CarboN-IR environmental cell)

**Experiment control:

– PC/Windows, fully software controlled (LabView©). Automatic acquisition of all spectral/geometric configurations. Automatic control and acquisition of spectra for a series of temperatures.

**Acquisition time:

– typical: 15 mn for 200 spectral channels in visible (S/N dependent). 1h15 for a full vis-NIR spectrum (0.4-4.2µm) at nominal resolution and sampling.
– total: 15 hours for 100 spectral channels and 100 geometries

**Current state of system:

– 0.35 – 4.8 µm range: fully calibrated
– polarization: tested (not available for external users)
– low temperature: tested in cold room down to -20°C ; in SERAC down to -40°C, in CarboN-IR down to -200°C (73K)


Updated on 24 November 2020