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Imaging spectrometer and polarimeter research at the Optical Detection Lab, University of Arizona, is overviewed. Topics include snapshot imaging spectroscopy, white-light channeled imaging polarimetry, and infrared hyperspectral imaging polarimetry.

The imaging polarimeter using the Savart plates is modified for use with the polychromatic light by incorporating an imaging system utilizing diffractive lenses. Its feasibility is numerical simulated for the visible light with 50nm-bandwidth.

Hyperspectral image cubes are usually obtained from direct measurement (e.g. satellites) and by using numerical reconstructions from imaging spectrometers. Such objects are three dimensional and consist of 2D spatial data layered by wavelength in the third dimension. The dominant image processing tasks for such information are compression and feature recognition. These tasks go hand-in-hand as most often these objects contain a huge amount of information that need to be processed further (and often very quickly) corresponding to the application. Wavelet transforms which have been utilized successfully for signals and images are applied here. The higher number of dimensions furnishes a number of different ways to do these transforms and some of these ways are more natural for hyperspectral data processing.

Replacement of current etched CGH dispersing elements with an electronically tunable liquid crystal element adds the ability to change the configuration of the Computed Tomographic Imaging Spectrometer (CTIS). The adaptation of the CGH design algorithm for the tunable disperser is presented.

Two-dimensional state of polarization (SOP) mapping of light plays an important role in many fields, including po-larimetric testing of optoelectronic devices, machine vision, and remote sensing. To enhance the measurement speed, we have developed a novel method of taking snapshot measurements of two-dimensional SOPs by use of birefringent prisms [1]. The major features of this method are that no mechanically-moving components, such as a rotating analyzer, are used, and that all the parameters related to the spatial distribution of SOP can be determined simultaneously and independently from a single interference pattern. The performance principle of this method is experimentally demonstrated by use of thin wedge prisms made of calcite.

Diffractive optical elements fabricated on flat and non-flat substrates frequently act as dispersive elements in imaging spectrometers. We describe the design and electron-beam fabrication of blazed and computer-generated-hologram gratings for slit and tomographic imaging spectrometer.