August 5, 2004
The advancement of computer simulation tools for high fidelity signature modeling has led to a requirement for a better understanding of effects of light scattering from surfaces. Measurements of the Bidirectional Reflectance Distribution Function (BRDF) fully describe the angular scattering properties of materials, and these may be used in signature simulations to quantitatively characterize the […]
January 1, 2004
Multispectral imaging is a well accepted technique for object discrimination. Hyperspectral imaging can result in highly complex optical systems that have frame rate limitations. For fast frame rate applications, dual band imaging can provide sufficient discrimination without sacrificing signal to noise ratio. The design of a fast frame rate (> 200 Hz) SWIR/MWIR and MWIR/LWIR […]
September 28, 1999
The Microwave Limb Sounder (MLS) is a limb-sounding radiometer sensing emissions in the millimeter and sub- millimeter range. MLS will contribute to an understanding of atmospheric chemistry by assessing stratospheric and tropospheric ozone depletion, climate forcings and volcanic effects. The heart of the antenna is the primary reflector, constructed from graphite/cyanate composites in a facesheet/core […]
October 7, 1994
This paper presents a description of a fully automated, computer-controlled Hemispherical Directional Reflectometer (HDR). It fills the need in many fields of research and development for a device with HDR measurement capabilities which is state-of-the-art in wavelength coverage to 25.0 μm and higher, angular polarization resolved coverage 20 to 80 degrees, partition of reflected radiation […]
February 12, 1993
Commonly used methods of developing paints and evaluating their performance involve calculating the signatures of vehicles and backgrounds, this requires experimental determination of the directional and bidirectional reflectance of the surfaces involved. This paper describes the measurements required, the instruments used to make such measurements, and computer codes and techniques used for paint development and […]