Martínez-Herrero, Rosario and Maluenda, David and Juvells, Ignasi and Carnicer, Artur


“We introduce a new method for producing optical needles with tunable length and almost constant irradiance based on the evaluation of the on-axis power content of the light distribution at the focal area. According to theoretical considerations, we propose an adaptive modulating continuous function that presents a large derivative and a zero value jump at the entrance pupil of the focusing system. This distribution is displayed on liquid crystal devices using holographic techniques. In this way, a polarized input beam is shaped and subsequently focused using a high numerical aperture (NA) objective lens. As a result, needles with variable length and nearly constant irradiance are produced using conventional optics components. This procedure is experimentally demonstrated obtaining a 53λ-long and 0.8λ-wide needle.”

Link to Publications Page

Publication: Scientific Reports

Issue/Year/DOI: Scientific Reportsvolume 8, Article number: 2657 (2018)
DOI: 10.1038/s41598-018-21007-7