Tight focus of light using micropolarizer and microlens
MetadataShow full item record
Using a binary microlens of diameter 14 μm and focal length 532 nm (NA = 0.997) in resist, we focus a 633 nm laser beam into a near-circular focal spot with dimensions (0.35 ± 0.02)λ and (0.38 ± 0.02)λ (λ is incident wavelength) at full width half-maximum intensity. The area of the focal spot is 0.105λ2. The incident light is a mixture of linearly and radially polarized beams generated by reflecting a linearly polarized Gaussian beam at a 100 μm 100 μm four-sector subwavelength diffractive optical microelement with a gold coating. The focusing of a linearly polarized laser beam (the other conditions being the same) is found to produce an elliptical focal spot measuring (0.40 ± 0.02)λ and (0.50 ± 0.02)λ. To our knowledge, this is the first implementation of subwavelength focusing of light using a pair of micro-optic elements (a binary microlens and a micropolarizer).
Stafeev , S S , O'Faolain , L , Kotlyar , V V & Nalimov , A G 2015 , ' Tight focus of light using micropolarizer and microlens ' Applied Optics , vol 54 , no. 14 , pp. 4388-4394 . DOI: 10.1364/AO.54.004388
© 2015 Optical Society of America. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modifications of the content of this paper are prohibited. This is the author created, accepted version manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at http://dx.doi.org/10.1364/AO.54.004388.
Funding: European Research Council (ERC) (337508); Ministry of Education and Science of the Russian Federation (MK-4816.2014.2, NSh-3970.2014.9); Russian Foundation for Basic Research (14-07-31092, 14-07-97039, 14-29-07133, 15-07-01174).