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TecnOPTO organizes a workshop on ‘Structured Light, Polarimetry and Imaging’


Workshop

On November 25th, 2019 we organized a workshop entitled ‘Structured Light, Polarimetry and Imaging‘.

The workshop was held at the Institute of Bioengineering of UMH, and we could count with the participation of experts from different groups in Spain working in these related fields.

We thank all the participants and attendees to this extremely interesting and motivating reunion.


Martes, 26 de noviembre de 2019 Sin comentarios

New paper in OLEN analyzing the diffraction efficiency of stepped gratings in large phase modulation SLMs


OLENOur new publication is available in Optics & Lasers in Engineering, entitled Diffraction efficiency of stepped gratings using high phase-modulation spatial light modulators.

We study the diffraction efficiency of linear phase (blazed) diffraction gratings displayed onto SLMs that exhibit a large phase modulation range, reaching a maximum phase modulation of 8pi or 10pi radians. We analyse these effects for their important implications in the Nyquist limit for diffractive elements

The paper has been done in collaboration with our friends at San Diego State University.


Domingo, 3 de noviembre de 2019 Sin comentarios

New paper in Optics Letters on breaking the Nyquist limit for diffractive lenses with high phase modulation displays


OL FIGWe 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.


Jueves, 27 de junio de 2019 Sin comentarios

Julio César Quiceno, from Universidad del Valle, Cali, joins TecnOpto


Dyz6KvlU8AAYqsiJulio 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!

 


Miércoles, 13 de febrero de 2019 Sin comentarios

New paper in Optics Express about Guoy phase effects on the propagation of vector beams


GuoyOur new paper in Optics Express entitled Gouy phase effects on propagation of pure and hybrid vector beams reports a theoretical simplified model and experimental analysis of the Gouy phase effects on vector beams. Experimental results at various axial planes, before and past the focus, are obtained by using a simplified liquid-crystal spatial light modulator-based optical system that allows the easy generation of these beams. Furthermore, a new alternative optical set-up that is devoid of moving elements is demonstrated, which simplifies this study.

We experimentally verify the differences between pure and hybrid vector beams upon propagation. While the first ones remain stable, hybrid vector beams show Gouy phase effects that demonstrate an optical activity where the local polarization states rotate by an angle that depends on the propagation distance.

This study has been conducted in collaboration with our friends at San Diego State University, Prof. Jeffrey A. Davis and Prof. Don M. Cottrell.


Martes, 29 de enero de 2019 Sin comentarios

New paper in Optical Engineering about a holographic projection system


OEng2A new paper of ours is published in the journal Optical Engineering entitled Holographic projection system with programmable control of state of polarization, focus plane, and size of the reconstruction

This work presents a holographic projection system based on the encoding of computer-generated holograms onto a spatial light modulator. We show how the size, location, and polarization state of the output can be controlled completely electronically, without physically moving any element in the system. And we show that the system is capable to produce optical logical operations by superimposing two different images encoded onto orthogonal polarization states.

The work has been done with our friends at the Department of Physics at San Diego State University.

 


Jueves, 27 de diciembre de 2018 Sin comentarios

Prof. Asticio Vargas visits TecnOPTO Lab


Asticio2During the last two weeks we had the pleasure of receiving our friend Asticio Vargas, from Departamento de Ciencias Físicas, Universidad de La Frontera, Temuco, Chile.

We have been advancing in new experiments and new projects. The fruitful UMH-UFRO collaboration continues in good shape.


Categories: Collaborators, International, Projects Tags:

Viernes, 21 de diciembre de 2018 Sin comentarios

New paper in Optics & Lasers in Engineering with a geometric phase lens based system to analyze vector beams


VortexWe published a new paper in Optics & Lasers in Engineering entitled Geometrical-phase lens based optical system for the spin-splitting of vector beams

In this work we combine a geometric phase lens and a telescope system to produce an optical system with two polarization controlled real foci with equal magnification. And we apply it to characterize vortex beams and vector beams, splitting longitudinally the circular polarization components and focusing them into different axial planes.

This work was develop din collaboration with our friends Asticio Vargas and Fabián Torres-Ruiz, from Universidad de La Frontera, Temuco (Chile). And it is part of the PhD Thesis of Aarón Cofré.


Sábado, 14 de julio de 2018 Sin comentarios

Aarón Cofré presents his PhD Thesis on diffractive optics systems for the generation of optical vortices and structured polarized beams


AaronOn July 10th 2018, Aarón Cofré presented the defense of his PhD Thesis entitled Development of advanced diffractive systems for the generation of optical vortices and structured polarized beams.

The Thesis has been supervised by Ignacio Moreno and Asticio Vargas, and included various experimental studies on how to generate optical vortices and vector beams.

The results of the thesis resulted in four articles published in the journals European Journal of Physics, Optics & Lasers Technology, Optics Express and Optics & Lasers in Engineering respectively.

In the picture, Aarón with the supervisors and the members of the jury.

 

 

 


Miércoles, 11 de julio de 2018 Sin comentarios

New paper on Optics Letters with a design for an achromatic retarder system with tunable retardance


Fig

We published a new paper in Optics Letters entitled Achromatic linear retarder with tunable retardance.

In this work we present a universal design and proof-of-concept of a tunable linear retarder of uniform wavelength response in a broad spectral range. It consists of two half-wave retarders (HWR) between two quarter-wave retarders (QWRs), where the uniform retardance can be tuned continuously by simply rotating one of the HWRs. A proof-of-concept of this design is built by using commercially available Fresnel rhomb retarders that provide retardation with almost wavelength uniformity in the visible and near infrared from 450 to 1550 nm. The system is experimentally demonstrated to control the state of polarization of a super-continuum laser.

The work has been developed in collaboration with Asticio Vargas, from Universidad de la Frontera, Chile. And it is part of the PhD thesis of Abdelghafour Messaadi.


Sábado, 7 de julio de 2018 Sin comentarios