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Systematic Approach for Describing the Geometry of Spectrophotometry



E A. Early


In the field of spectrophotometry, the values of the measured quantities depend upon the measurement geometry. Therefore, it is imperative to completely describe the measurement geometry. Many documentary standards specify the geometry for a particular application. However, to accurately specify the geometry, a general, basic understanding of the relevant parameters for describing the geometry is required. A systematic approach for describing the measurement geometry is presented, which will hopefully contribute positively to documentary standards. The key to describing the geometry is to consider the illuminator and receiver of the instrument as optical systems with pupils and windows. It is these optical systems, together with the reference plane, that determine the sampling aperture of the instrument. The geometry is then completely described by the relations between the sampling aperture and the optical systems of the illuminator and receiver. These concepts are illustrated by considering three configurations of pupils and windows relative to the focal point of an optical system.
Proceedings Title
Oxford Conference on Spectroscopy | 4th | Fourth Oxford Conference on Spectroscopy | SPIE
Conference Dates
June 1, 2002
Conference Title
Proceedings of SPIE--the International Society for Optical Engineering


appearance, color, geometry, optical systems, optics, reflectance, spectrophotometry, transmittance


Early, E. (2003), Systematic Approach for Describing the Geometry of Spectrophotometry, Oxford Conference on Spectroscopy | 4th | Fourth Oxford Conference on Spectroscopy | SPIE (Accessed June 18, 2024)


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Created August 1, 2003, Updated February 17, 2017