An imaging spectrometer is disclosed that comprises imaging means for
dividing a received image into two or more spatially separated images and
means for detecting each spectral image, and is characterized in that the
imaging means comprises at least one polarizing beam splitter. The
polarizing beam splitter may be a Wollaston prism. In one embodiment of
the invention, the imaging means comprises image replication means to
produce two or more spatially separated images, and one or more filter
elements such as dichroic filters which act to alter the spectral
characteristics of one or more of the spatially separated images. In a
further embodiment of the invention the imaging means comprises one or
more spectral replication means arranged in optical series, each spectral
replication means comprising an optical retardation element and a
polarizing beam splitter.