Projects
Design and benchmarks of laser manufactured photonic elements in nonparaxial imaging
Summary
Structured light – electromagnetic waves with a strong spatial inhomogeneity of amplitude, phase, and polarization – has occupied far-reaching positions in both optical research and applications. In a recent publication (Light: Science and Applications) we have shown that structured nonparaxial THz light in the form of Airy, Bessel, and Gaussian beams can be generated in a compact way using exclusively silicon diffractive optics prepared by femtosecond laser ablation technology. The accelerating nature of the generated structured light is demonstrated via THz imaging of objects partially obscured by an opaque beam block. Unlike conventional paraxial approaches, when a combination of a lens and a cubic phase (or amplitude) mask creates a nondiffracting Airy beam, we demonstrated simultaneous lensless non-paraxial THz Airy beam generation and its application in imaging systems. Images of single objects, imaging with a controllable placed obstacle, and imaging of stacked graphene layers are presented, revealing the potential of the approach to inspecting the quality of 2D materials.
Structured nonparaxial THz illumination was investigated both theoretically and experimentally with appropriate extensive benchmarks. The structured THz illumination consistently outperforms the conventional one in resolution and contrast, thus opening new frontiers of structured light applications in imaging, as it enables sophisticated estimates of the optical properties of the investigated structures. In this proposal, we design, manufacture, inspect and benchmark various photonic elements microfabricated using high-power laser ablation of SI wafers. We plan not only an extension of photonic elements for the structured nonparaxial illumination of targets but also to use produced photonic for light collection in single pixel nonparaxial imaging. The light collection is usually performed using lenses, so we will benchmark the photonic elements against conventional lenses.
Design of the optical focal line with polarization control for applications of laser microprocessing of transparent materials (OptiPol)
Summary
Photonics is recognized by the European Commission (EC) as one of the Key Enabling Technolgies. The combined part of the photonics is the laser microprocessing of transparent media. This is a complex process in which various transparent media are cut, diced and treated inside the volume. Such processes increasingly require unconventional laser beams, where the intensity distribution of the beam in the vicinity of the focus is very important. For this reason, it is vital to be able to control the structure of the beam and the spatial-temporal electromagnetic field distribution.
Polarization of electromagnetic field becomes very essential in laser microprocessing. There are more and more references in the scientific literature to the fact that the control of polarization can significantly improve the efficiency of laser field processing of transparent media utilising femtosecond pulses.
The Lithuanian laser industry companies working with the microprocessing of transparent media feel the need to perform both theoretical and experimental work in academic institutions. The present project will address the task of the Lithuanian laser industry related to the laser-based microprocessing of transparent media.
The main objective of the project is the formation of new vector and ultra-short pulsed beams with geometric phase elements. These innovative structure beams will be methodically considered as a laser microprocesing tools and will be systematically improved based on experimental results. In addition, numerical simulations will be performed to optimize the beam focal region and polarization for microprocessing of different types of transparent media.
During this project a new type of 2D and 3D geometric phase elements will be developed for the creation of specially designed pulsed beam for processing of transparent media. This would allow Lithuanian laser companies to compete globally while enabling a team of young researchers participating in the project to contribute to the creation of industrial prototypes and to learn how to smoothly communicate with the Lithuanian laser companies.
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PHABLABS 4.0, PHotonics enhanced fAB LABS supporting the next revolution in digitalization
12.2016 - 12.2019
Combining the World of Photonics and Fab Labs. The concept of PHABLABS 4.0 is based on combining the World of Photonics with the growing creative ecosystem of existing Fab Labs. Joining forces of top experts from 13 European photonics institutes and STEM-oriented organizations with Fab Lab stakeholders, PHABLABS 4.0 will deliver 33 Photonics Workshops, 11 Photonics Challengers and Photonics Toolkits tailored for three different target groups.
Site: http://www.phablabs.eu/