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Spatio-spectral scanning〔Grusche, Sascha. ( ''Basic slit spectroscope reveals three-dimensional scenes through diagonal slices of hyperspectral cubes'' ) ''Applied Optics'', OSA, June 2014. Retrieved on June 09, 2014.〕 is one of four techniques for hyperspectral imaging, the other three being spatial scanning,〔() ''Advancements in hyperspectral and multi-spectral imaging'', Retrieved June 10, 2014〕 spectral scanning 〔Gat, Nahum. () ''Imaging spectroscopy using tunable filters: A review'', Proc. SPIE Vol. 4056, 2000. Retrieved June 10, 2014.〕 and non-scanning, or snapshot hyperspectral imaging. The technique was designed to put into practice the concept of 'tilted sampling' of the hyperspectral data cube, which had been deemed difficult to achieve.〔Bershady, Matthew. () ''3D Spectroscopic Instrumentation''. In: “3D Spectroscopy in Astronomy, XVII Canary Island Winter School of Astrophysics,” eds. E. Mediavilla, S. Arribas, M. Roth, J. Cepa-Nogué, and F. Sánchez, Cambridge University Press, 2010. Retrieved June 10, 2014.〕 Spatio-spectral scanning yields a series of thin, diagonal slices of the data cube. Figuratively speaking, each acquired image is a 'rainbow-colored' spatial map of the scene. More precisely, each image represents two spatial dimensions, one of which is wavelength-coded. To acquire the spectrum of a given object point, scanning is needed. Spatio-spectral scanning combines some advantages of spatial and spectral scanning: Depending on the context of application, one can choose between a mobile and a stationary platform. Moreover, each image is a spatial map of the scene, facilitating pointing, focusing, and data analysis. This is particularly valuable for irregular or irretrievable scanning movements. Being based on dispersion, spatio-spectral scanning systems yield high spatial and spectral resolution. == Prototypical system == A prototypical spatio-spectral scanning system, introduced in June 2014, consists of a basic slit spectroscope (slit + dispersive element) at some suitable, non-zero distance before a camera. (If the effective camera distance is zero, the system is applicable to spatial scanning). The imaging process is based on spectrally-decoded camera obscura projections: A series of projections from a continuous array of pinholes (= the slit) is projected onto the dispersive element, each projection contributing a rainbow-colored strip to the recorded two-dimensional image. The field of view in the wavelength-coded spatial dimension asymptotically approaches the dispersion angle of the dispersive element as the camera distance from the dispersive element approaches infinity.〔 Scanning is achieved by moving the camera transverse to the slit (stationary platform), or by moving the entire system transverse to the slit (mobile platform). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Spatiospectral scanning」の詳細全文を読む スポンサード リンク
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