As visibility decreases, crew workload increases resulting in reduced operational capability. As a consequence it is useful to define standard operational levels defining operational constraints based on visibility range. For given atmospheric conditions, visibility varies with wavelength meaning that the operational level may vary depending on the sensor waveband. Results from a number of previous authors are combined to present an updated and integrated set of spectral attenuation and visibility curves from the visible through the millimeter wave regime. These curves show attenuation through standard and humid atmospheres and the effects of various levels of rain and fog. Obscurant particle size ranges are shown to help explain the observed phenomenology. In addition, work from a number of other authors is combined to relate standard meteorological measurements (densities or rates) to visibility. These results are compared with the spectral attenuation curves. The result is an ability to relate obscurant density or rate to attenuation or visibility and hence operational level at any wavelength from visible through the millimeter wave regime.
John N. Sanders-Reed and Stephen J. Fenley, "Visibility in degraded visual environments (DVE)," Proc. SPIE 10642, Degraded Environments: Sensing, Processing, and Display 2018, 106420S (Presented at SPIE Defense + Security: April 18, 2018; Published: 2 May 2018); https://doi.org/10.1117/12.2305008.
Conference Presentations are recordings of oral presentations given at SPIE conferences and published as part of the conference proceedings. They include the speaker's narration along with a video recording of the presentation slides and animations. Many conference presentations also include full-text papers. Search and browse our growing collection of more than 14,000 conference presentations, including many plenary and keynote presentations.
Study of self-shadowing effect as a simple means to realize nanostructured thin films and layers with special attentions to birefringent obliquely deposited thin films and photo-luminescent porous silicon