We demonstrate a reconfigurable optical filter implemented using a phase-only
two-dimensional liquid crystal on silicon spatial light modulator. To achieve
this we utilize two different approaches leading to two different
configurations in the modulator. The first one, based on a spatially patterned
diffractive lens permits to obtain the desired spectrum along the optical axis
and, in the second one, based on a generalized spectrometer, it is found
outside of the optical axis. Experimental results show good agreement with the
theory and indicate the validity of this technique.Comment: 14 pages, 3 figures, replaced the older version with a newer
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