Thermal Infrared Multispectral Scanner (TIMS)

Instrument Description:

The TIMS system consists of a scan head with thermal reference sources, a motor controller, a six channel spectrometer, a system control console (inside the aircraft), and a digitizer.

The instrument provides six-channel spectral data in the thermal infrared region of the electromagnetic spectrum from 8.2um to 12.2um using the six-element mercury cadmium telluride array detector. TIMS has a channel sensitivity of approximately 0.1 degrees C and is used whenever an accurate measure of spectral radiance or brightness temperature of the earth's surface is needed.

Research applications include characterization of rocks, minerals, soils, vegetation, and surface coatings. Rock units can be identified for their free silica, carbonate, clay, and sulfate contents. Information about alteration and weathering can be obtained from TIMS data as well as an understanding of surface emissivity, porosity, grain size, and roughness. TIMS data is valuable in determining water surface and forest canopy temperatures. Relationships between canopy temperature and levels of green leaf biomass in newly planted clear-cut areas can be determined. Perturbed ecosystems can be monitored by observing surface temperature of vegetated areas which are cooler than surrounding nonvegetated areas.

TIMS Channel Wavelengths

     channel            wavelengths
1 8.2 - 8.6 um
2 8.6 - 9.0
3 9.0 - 9.4
4 9.4 - 10.2
5 10.2 - 11.2
6 11.2 - 12.2

Other TIMS performance parameters are

     scan rates (selectable)      7.3, 8.7, 12, 25 scans per second
aperture 7.5 inches
IFOV 2.5 mrad
roll correction plus or minus 15 degrees
reference sources 2 controlled thermal blackbodies