Basically, imaging spectroscopy, or hyperspectral imaging, is a happy fusion of spectroscopy and imaging processing.

 

Imaging spectroscopy can be seen either as an extension of classical image processing or an enhancement of classical spectroscopy. The simplest case is using a black and white camera that captures the grey-scale values of objects - yielding high surface resolution but no spectral information. A color camera, on the other hand, with three image sensors or a sensor with Bayer color filter, will deliver a multi-spectral image with comparably high spatial resolution and three relatively broad-band color channels of red, green and blue, yet with a relatively low spectral resolution. Finally, a spectral imaging system - it operates with just one sensor and a tunable narrow-band filter placed in the optical path to select a frequency. Alternatively, it functions as a so called push-broom scanner to perform, usually via mechanical feed of test object or spectrometer, a line-based scan. For every pixel in every line, the spectrum is captured and stored.

 

Both methods use significantly more color channels. This is why they are called hyperspectral: they deliver high spatial resolution and, at the same time, high spectral resolution. The measured data of the X- and Y-coordinates and the radiation components at certain frequencies are located in a three-dimensional data space (cube).

 

Imaging spectroscopy has proved its worth in the acquisition of geological parameters from the air or by satellite in order, for example, to answer environment-related questions such as relating to the water quality of lakes. On a microscopic scale, the method can be applied to good advantage for multi-channel spectral analysis of light-emitting semiconductors, or in bio-medical and chemical sample analysis. Furthermore, hyperspectral imaging can be perfectly suited for industrial process monitoring for waste sorting, fruit and vegetable inspection, moisture measurements, fat analysis, web inspection, … and many more applications.

 

Contact XenICs to find an optimal solution for your hyperspectral imaging application.