D2.1 Definition of a database of optical parameters of obscurants

According to the DVE-DELETE Technical Program, the aim of this document is the definition and description of a database of spectral and optical parameters of obscurants. This document, along with the relevant data files, constitutes the Deliverable D2.1 as defined in the DVE-DELETE technical program The database includes both natural and artificial obscurants, and reports the optical parameters needed to calculate the impact of the obscurants on the performance (i.e. resolution) of optical imagers in the different wave bands. The technical content of the document is organized as it follows: the Section 4 outlines the impact of the aerosol on the performances of an optical system, with particular attention of the effect of the scattering on the degradation of the optical resolution. The main parameters of the aerosol for the description of these effects are identified. Section 5 describes the general characteristics and properties of several types of natural and artificial aerosols and obscurants, such as different kinds of fogs, clouds, rain, marine aerosols, dust, smokes, as well as several types of war smokes, used for concealment in the battlefield. In Section 6 the spectral properties of these aerosols and obscurants are described in details, by reporting the spectra of the absorption, scattering and extinction coefficients in a broad wavelength range encompassing the SWIR, MWIR and LWIR spectral region. Data are derived from open publications, and scientific databases. In some cases specific simulations based on internally developed codes were carried out to retrieve the spectral data from the physical properties of the aerosols (refractive indexes, size distributions). Data format and measurement unit were harmonized to constitute a homogeneous database. Finally, an Appendix resuming the available data sets is reported.