Scanning radiometric imager (SRI)

As commercially available lasers become smaller and more powerful, antipersonnel laser weaponry become a more probable threat. In studying the effects of lasers on aircrew personnel and mission impact, major emphasis has been placed on how an aircraft canopy scatters laser light inside the cockpit. In turn, experimental validation required a device that could radiometrically measure how light scatters within a volume, leading to the design and fabrication of the Scanning Radiometric Imager (SRI). The Laser Sensor Technology Laboratory, a division of Wright Laboratory's Avionics Directorate, designed and built the SRI in less than ten months. The design employs all reflective optics and an off-axis parabolic mirror to minimize image aberrations, reduce light scatter, and eliminate secondary surface reflections. A two-axis scanner allows the SRI to cover a square 40 degree field of view. SRI uses a portable personal computer to handle the data acquisition and control the scanning process. The control software has a graphical user interface providing the operator with a simple, straightforward way of changing the data collection modes and scan parameters. A process that assembles multiple scans extends the total dynamic range to over six decades by merging just two scans. The aim of the research is to validate ongoing eye modeling efforts and help predict pilot performance impairment under hostile laser illumination conditions.