Hyperspectral

Keith C.G., RepaskyK.S., et al. Monitoring effects of a controlled subsurface carbon dioxide release on vegetation using a hyperspectral image. 2009 International Journal of Greenhouse Gas Control 3 626-632. 

Figure 2 Data cube generation in mapping and imaging. The four-dimensional hyperspectral data cube contains the full spectral information, absorbance vs. wavenumber (v, cm ), for each x,y pixel from the imaged area, as is shown above. A horizontal slice through that cube contains a chemical image (e.g., band intensity at selected v for each x,y pixel of the image) as is shown below. The latter result could be obtained by Global Imaging (in which only the intensity distribution of a certain band over the imaged area would be recorded).

Near-infrared chemical imaging (NIR-CI) refers usually to the hyperspectral imaging of samples using typically wavelengths from 0.9 to 2.5 pm (NIR region) and an FPA detector. There are some major methodical and instrumental differences between NIR and IR imaging. 

The fourth chapter by James McGuinty et al. describes the more advanced forms of time-domain FLIM. While not immediately available on commercial instruments this chapter should give the reader an idea what the current state-of-the-art is in terms of FLIM instrumentation, and perhaps what to expect on future commercial instruments. Real-time FLIM, combined FLIM-spectral imaging, hyperspectral FLIM-imaging, combined lifetime-anisotropy imaging and some of their applications are covered here. 

Spectral FLIM involves measuring the apparent lifetimes in a preparation at many wavelengths with the assistance of a spectrograph or a series of filters (see also Chapter 4, Figs. 4.7 and 4.8 depicting hyperspectral FLIM in the time domain). The goal of the measurement is similar to that of the multifrequency approach ... 

Fig. 4.7. Application of hyperspectral FLIM to an unstained fixed section of human artery excited at 400 nm (A) schematic of a line-scanning hyperspectral...

Figure 75-2 shows third-order data or a hyperspectral data cube where the spectral amplitude is measured at multiple frequencies (spectrum) with X and Y spatial dimensions included. Each plane in the figure represents the amplitude of the spectral signal at a single frequency for an X and Y coordinate spatial image. 

Asner G, Heidebrecht K. Spectral unmixing of vegetation, soil and dry carbon cover in arid regions comparing multispectral and hyperspectral observations. Int. J. Remote Sens. 2002 23 3939-3958. 

K.H. Esbensen and T.T. Lied, Principles of image cross-validation (ICV) representative segmentation of image data structures, in Techniques and Applications of Hyperspectral Image Analysis, H. Grahn and P. Geladi (eds). Chap. 7. (155-180), John Wiley Sons, Ltd, Chichester, 2007. 

The phyllic alteration zone coincides with a subtle but consistent shift in the dominant AlOH peak in the short-wave infrared spectrum ( 2210 nm) to slightly lower wavelengths, consistent with an inner white mica-ferroan carbonate mineral assemblage. A preliminary analysis of hyperspectral data over the visible to near infrared range suggests that ferroan carbonates may be detected but not reliably quantified. However, TIR data allow calcite and ferroan carbonate to be distinguished, and may also detect increasing Fe content in ferroan dolomite as mineralized structures are approached. 

Figure 4.42 Examining microarray backgrounds using hyperspectral scanning. (From Martinez, M.J. et al., Nucleic Acid Res., 31(4), 1-8, 2003. With permission.)...

DRASTIC) A hyperspectral FT-IR-based approach to rapid screening for metabolite overproduction. Hna/yhca Chimica Acta, 348, 273-282. 

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