We experimentally verify the focusing characteristics of dichromats, a new class of circular-symmetric diffractive-optical lenses that generate, in the same focal plane, focal spots for one wavelength and ring-shaped spots with central nodes for another wavelength. Using a dichromat, we illuminate a thin photochromic layer and demonstrated point-spread-function compression of the transmitted focal spot.
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| http://dx.doi.org/10.1364/ol.33.002916 | DOI Listing |
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