Viewing geometry

Starting with the selective chopper radiometers (SCR) on Nimbus 4 and 5, the Department of Physics at the University of Oxford developed a series of instruments observing infrared emission from the atmosphere. A pressure modulated instrument flew on Nimbus 6 and the Stratospheric and Mesospheric Sounder (SAMS) flew on Nimbus 7 (Table 1). SAMS measured in limb viewing geometry the gases C02, H20, CO, N20, CR, and NO in the stratosphere and mesosphere. An improved version of ISAMS flew aboard the UARS and added channels for N02, N205, HN03, 03, and H20 (e.g. Barnet et al., 1992) (Table 1). 

Satellite instrumentation orbiting the earth view the stratosphere in limb and nadir viewing geometries. In addition both solar, lunar and stellar occulation have also been exploited very successfully. 

The limb-viewing geometry can be correctly modeled by Monte Carlo simulation of radiative transfer. We have developed a backward Monte Carlo algorithm "Siro" especially... 

Future spacecraft missions to solar system objects are primarily being oriented towards remote-sensing experiments, in contrast to the soft-landed in situ experiments and sample-return initiatives during the 1970 s and 1980 s. Because reflectance spectroscopy has become one of the most important investigative techniques in the planetary sciences, current and planned space missions for the 1990 s and 21st century should include visible and near-infrared spectrometers in their instrument payloads. Reflectance spectral measurements from space would provide more favourable viewing geometries, eliminate problems due to telluric water and C02, and improve the resolution of areas scanned on a nearby planetary surface. 

The instruments used for color measurements are nowadays spectrophotometers determining the reflectance of a sample. Three-filter colorimeters, trying to mimic the spectral response of the human eye are now next to obsolete. For applications in the field of uni-pigments photometer illuminating/viewing geometries are standardized as methods A and B, and are designed to suit the individual application (see Section 1.4.2). For standards, see Table 1.1 ( Color Differences, Conditions/ Fvaluation... ). 

Figure 28-8 Viewing geometries for ICP sources, (a) Radial geometry used in ICP atomic emission spectrometers (b) axial geometry used in ICP mass spectrometers and in several ICP atomic emission spectrometers.

Thus, one can conclude that different SAR systems and their viewing geometry can result in highly different damping ratios of the same spill. 

The choice of the viewing geometry and illumination type (which is associated with the selection of the instmment)... 

R. Hartley, A. Zisserman, Multiple View Geometry in Computer Vision, Cambridge University Press, Cambridge, 2004. 

Thermoresistive Flow Sensors, Fig. 5 Side view geometry for a typical calorimetric flow sensor with a middle heater and upstream and downstream temperature sensor (Modifled from [2])... 

Viewing geometry n. The geometry by which the incident illumination is projected onto the sample and by which the observed light is collected and transmitted to the detector. 

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