Since 1990, many countries, including tech support the USA, Japan, and Europe, have launched a series of mature field imaging spectrometers which have been successfully applied in agriculture [14], food monitoring [15,16], vegetation observations [17], geological mapping [18], and other fields [19,20]. The unique advantages of field imaging spectrometers have catalyzed the development of field imaging spectroscopy and promoted further improvements in both field spectral measurements and aviation imaging spectrometry.Although China��s aviation imaging spectrometry is relatively mature [4,21], the development of ground-based imaging spectrometry has only just begun, and few applications using such equipment have been reported in China.

Recently, to narrow the gap between China and the countries mentioned above, we have developed a new field imaging spectrometer system (FISS), based on the aviation push-broom imaging spectrometer (PHI) [22], self-developed in China at the Institute of Remote Inhibitors,Modulators,Libraries Sensing Applications and the Shanghai Institute of Technical Physics, as part of the Chinese Academy of Sciences. For indoor or outdoor measurements, the FISS instrument can obtain high-resolution images of targets (spatial resolution up to the cm or mm scale) and extract a complete spectrum of every pixel from images obtained in the wavelength region covered. Our experiments [23�C25] using FISS confirmed that it can greatly improve the efficiency of field spectral measurements, provide information for the analysis of structural spectra, decompose mixture spectra, and extract pure spectra.

Compared to those produced by traditional field spectrometers (e.g., ASD FieldSpec), the spectra derived by FISS may be considered pure. They are helpful for studying the mixing mechanism of surface units and analyzing spectral mixtures over varying spatial scales [24].The data acquired by the FISS instrument are A/D converter counts Inhibitors,Modulators,Libraries (Digital Number, DN), in arbitrary units mainly defined by the integration time and solar lamp intensity [26]. If DNs are not further converted to reflectance or absorbance, they have no physical meaning. Therefore, to make quantitative studies of surface features, accurate radiometric and spectral Inhibitors,Modulators,Libraries Inhibitors,Modulators,Libraries calibration of the data must be performed [26�C29]. The methodologies and measurements for sensor calibration have been studied in detail, and can often be grouped into three stages.

These are laboratory calibration prior to launch, in-orbit/in-flight calibration, and vicarious or ground-look calibration [30�C34]. As our FISS instrument is mainly used for AV-951 field measurements, this paper describes only the first stage. There are two major tasks in laboratory calibration. The first is spectral calibration, which consists selleck chemicals Gefitinib of determining the spectral response function for each band through the centroid wavelength and spectral resolution. It is calculated as the full-width at half-maximum (FWHM) of the spectral response function for each band.