APEX-Airborne Prism Experiment: The Realization Phase of an Airborne Hyperspectral Imager

APEX (Airborne Prism EXperiment) is a project of the European Space Agency ESA focusing on high accuracy simulation, calibration and validation for spaceborne remote sensing instruments. The instrumentation comprises a hyperspectral imager for various standard airborne platforms, a fixed installed calibration home base and a complete facility for data processing and archiving. The pushbroom-type instrument accommodates two spectrometer channels covering a spectral range from 0.38 up to 2.5 micron. The spatial/spectral resolution amounts to 1000 samples at 28-degree field of view with 312 spectral bands. The overall instrument design and its built-in characterization unit will allow excellent performance stability under various flight conditions. The presentation will focus on the design, development and realization phases of the instrument and discuss various highlights of technical achievements, as there are the infrared HgCdTe detector with extended array format for the short wave infrared channel, the thermal/mechanical stabilization of the spectrometer and the realization of the infrastructure for high accuracy characterization and calibration of the instrument.