Conference Agenda

Session

TOM Applications S7: Applications of Optics and Photonics

Time:

Thursday, 28/Aug/2025:

8:30am - 10:00am

Session Chair: M.Teresa Flores-Arias, Universidade de Santiago de Compostela, Spain

Location: Collegezaal A

1st and 2nd Floor

Presentations

8:30am - 9:00am
INVITED

Sensing applications based on all-optical excitation and interrogations of forward stimulated Brillouin scattering

Martina Delgado Pinar

University of Valencia, Spain

Authors: Carlos Álvarez-Ocampo, Juan Julián-Barriel, Anna I. Garrigues-Navarro, Aleksander S. Paterno, Martina Delgado-Pinar, Antonio Díez, Jose Luis Cruz, Miguel V. Andrés

9:00am - 9:15am

Analysing the applicability of twisted nematic liquid crystals in non-classical Mueller polarimetry systems

Monika Salamaga, Władysław Artur Woźniak

Wrocław University of Science and Technology, Poland

In the classical polarimetric solutions, the light polarization states generator (PSG) and analyzer (PSA) are placed on opposite sides of the medium. Such a solution is difficult to realized and even impossible for some media. An interesting alternative are configurations in which light passes through the PSG, the test medium and, after reflecting off the mirror, comes back again through the medium and the same module (PSG) acting as a PSA. This arrangement can be named one-way double pass Mueller polarimeter. Crucial to the system capabilities is the single module PSG/PSA design. This work verifies the possibility of using in them twisted nematic liquid crystals (TNLCs). There are noticeable differences in the quality of the polarimeter depending on the used components (linear polarizer with a single TNLC, two TNLCs or a combination of TNLCs with a liquid crystal variable retarder). Based on the measurement results, numerical models were created and optimized by minimizing condition number to find the best set of PSG/PSA configurations. The one-way double pass polarimetric systems were then tested in the laboratory. The results show that the use of TNLCs overcomes some measurement limitations and increases the system stability, compared to other solutions proposed in the literature.

9:15am - 9:30am

A non-invasive multimodal approach to understand plastic degradation in design objects

Sabrina Samela¹, Paulina Guzman Garcia Lascurain¹, Alessia Di Benedetto¹, Luca Andena², Irene Bargagli³, Francesca Rosi³, Daniela Comelli¹

¹Department of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133, Milano, Italy; ²Department of Chemistry, Materials and Chemical Engineering “Giulio Natta”, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133, Milano, Italy; ³Istituto di Science e Tecnologie Chimiche “G. Natta” (CNR-SCITEC), Via Elce di Sotto 8, 016280, Perugia, Italy

This study explores the early detection of degradation in plastic-based cultural heritage objects using non-invasive spectroscopic techniques. The results on artificially aged ABS specimens revealed degradation markers at low exposure levels. Changes in polymer composition were then correlated with mechanical stiffening and increased friction. The approach offers valuable tools for in situ monitoring and preventive conservation of modern art and design objects.

9:30am - 9:45am

Investigations into a free-form grinding process chain at the example of a beam shaping element

Sebastian Henkel, Marcel Binder, Jens Bliedtner, Aliaksei Kobylinskiy, Robert Brunner

Ernst-Abbe University of Applied Sciences Jena, Germany

The production of optical free-form surfaces requires a high level of precision and surface quality. The process chain presented combines pre-grinding, fine grinding and ultra-fine grinding using a 5-axis CNC machine in order to achieve high shape accuracy and surface quality. The presented process chain makes it possible to produce free-form surfaces with high geometric precision and optical qualities.