Here you can see Ignacio Moreno’s talk about Optics & Photonics at the Day of Light, the workshop organized by COSCE – the Confederation of Spanish Scientific Societies on June 6th, 2019.
You can access the complete workshop at the following link
COSCE – the Confederation of Spanish Scientific Societies organized in June 6th a workshop to commemorate the Day of Light. Ignacio Moreno participated as President of SEDOPTICA, the Spanish Society of Optics. More information at: link
In the next video you can see a report recorded by UNED – the Spanish National University of Distance Education, which has bee broadcast at TVE2.
In his talk entitled «Two-dimensional geometric phase vortex grating based on the optimal triplicator design», David presented the design and characterization of a liquid-crystal geometric phase diffraction grating that generates 3×3 diffraction orders with vortex beams of different topological charges, and showed the operation of this grating as a vortex detector. These results have recently been published in Optics Express: link to the paper.
Julio César presented a poster entitled “Hybrid vector beams generated by cascaded q-plates” where he demonstrated a q-plate-based optical system capable of generating a variety of hybrid vector beams, and showed the rotation of their polarization pattern when comparing the near field and the far field captures. This optical system is more compact than those based on SLMs whilst bearing a notable degree of versatility.
They have enjoyed the interesting conferences, scientific discussions and networking opportunities of this conference hosted by the OSA student chapter at ICFO and backed by the International OSA Network of Students. Link to the conference.
We published a new paper in Optics Letters entitled Encoding lenses with focal lengths lower than the Nyquist limit using high phase-modulation displays. In this work we show that focal lengths much lower than the classical Nyquist limit can be encoded onto spatial light modulators having a large phase-dynamic range.
Experimental results are included with a display showing 10π phase modulation reducing the Nyquist limit by a factor of about 1/10. We used a Hamamatsu reflective LCoS device designed for use in the near infra-red (NIR) range, but operated with visible light in order to achieve such large modulation regimes.
The work has been done in collaboration with our friends at the Department of Physics of San Diego State University.
We had the visit to UMH of Yann Amouroux, OSA Europe Director, in the frame of his intense tour in Spain to visit Optics & Photonics centers.
Good interaction to contribute to the SEDOPTICA-OSA collaboration, and also with TecnOPTO and other photonics colleagues at UMH.
One day after the International Day of Light, Dr. Carlos Hernandez Garcia from USAL gave a seminar at TecnOPTO about Ultrafast Structured Laser Pulses – Extreme-Ultraviolet Vortex Beams Carrying Spin and Orbital Angular Momentum.
A great talk and a great discussion after the talk.
In May 16th 2019, we celebrated the International Day of Light. We had the visit of Dr. Carlos Hernández García, from the Research Group in Applications of Laser and Photonics Applications (ALF-USAL) of the University of Salamanca, a recognized expert in the generation of ultra-fast structured laser pulses
He imparted an excellent talk entitled Sculpting laser pulses, where he explained the Nobel Prize in Physics 2018, awarded to Arthur Ashkin, Gérard Mourou and Donna Strickland for their breakthroughs in laser physics. The talk can be viewed on line at the following link.
This conference was organized by the Local Section of Alicante of the Royal Spanish Physics Society (RSEF), in collaboration with the Department of Physics, the Institute of Bioengineering and the Polytechnical School of UMH, and was attended by over 80 students and faculty members.
We were also supported by SPIE, that provided Women in Optics agendas!
We published a new paper in Optics Express entitled Optimal triplicator design applied to a geometric phase vortex grating. It shows a liquid-crystal diffraction grating based on the optimal triplicator design fabricated as a geometric phase element. We analyze the polarization properties of this special diffraction grating and then use embedded spiral phases to design geometric phase vortex diffraction gratings. The fabrication of a two-dimensional version of such a design is demonstrated using a micro-patterned half-wave retarder, where the phase distribution is encoded as the orientation of the fast axis of the retarder.
This proof-of-concept element is made of liquid crystal on BK7 substrate where the orientation of the LC is controlled via photoalignment, using a commercially available fabrication facility. Experimental results demonstrate the parallel generation of vortex beams with different topological charge and different states of polarization.
This work is part of the PhD Thesis of David Marco, and it has been done in collaboration with our friends Aarón Cofré and Asticio Vargas, from Universidad de La Frontera, Temuco, Chile.
Our new paper in Journal of the Optical Society of America B is entitled Using birefringence colors to evaluate a tunable liquid-crystal q-plate. Here we show a tunable liquid-crystal commercial -plate from the company Arcoptix, operative in the visible and near-IR range. We study its spectral and color birefringence properties under broadband illumination.
We first characterize the spectral retardance function of the device in a wide range from 400 to 1600 nm and determine how it changes upon applied voltage.
Then we evaluate the color transmission characteristics when inserting the -plate between crossed and parallel linear polarizers. These color properties agree with the trajectory in the CIExy chromaticity diagram as the applied voltage changes.
Finally, we demonstrate that a simple visual inspection of the transmitted birefringence color perceived when placing the -plate between crossed polarizers can be used to obtain a rapid estimation of the -plate retardance at given wavelength ranges.
This work is the first paper of the PhD Thesis of David Marco.
Julio César Quiceno, from Universidad del Valle, Cali, Colombia, will be visiting researcher at TecnOpto for a period of six months.
We will be working together in new projects related to vector beams.
Welcome to Elche!