OPTODIGITAL INFORMATION PROCESSING AND DYNAMIC SPECKLE

Head:
- Dr. Myrian Tebaldi

Members and/or collaborators:
- Dr. Damián Gulich
- Dr. Joaquín Mendoza Herrera
- Dr. Ruth Dary Mojica Sepulveda
- Dr. Astrid Villamizar Amado
- Dr. Ingrid Medina Mojica
- C.C. Nelly Cap
- MSc Eng. Prof. Leandro Buffarini
- Eng. Eduardo Grumel
- Lic. Leopoldo Garavaglia

International collaborators:
- Dr. Daniel Sierra Sosa
- Dr. Alejandro Velez Zea
- Dr. John Fredy Barrera

Main research topics

  • Study of porous adsorbent materials with different textural properties using speckle techniques and optical vortices. Samples are characterized in response to water impregnation, analyzing the influence of intrinsic material inhomogeneity on overall properties.
  • Development of algorithms for the use of dynamic speckle in the detection of hidden topographies, such as reading through paper, paints, dirt, etc.
  • Application of dynamic speckle and optical vortex techniques to study atmospheric turbulence effects.
  • Synthesis and characterization of silver nanoparticles; morphology and size analysis using speckle techniques.
  • Application of machine learning techniques to analyze image propagation through turbulent media and dynamic speckle patterns for recognition, classification, tracking, and analysis of underlying physical phenomena.
  • Use of fractal and multifractal techniques to determine characteristics of time series from dynamical systems.
  • Application of speckle techniques to characterize tumor-derived extracellular vesicles (EVs).
  • Nanostructuring of materials via chemical methods modified by radiation for applications in photothermal therapy and virus detection.

Brief historical overview

The studies underlying this project originated as a branch of image processing within the framework of Fourier optics. Our experience in general aspects of information processing, particularly in the use of speckle, forms the basis of most of the research lines developed by the group.

Since the late 1980s, the group’s research has focused on the development of dynamic holography techniques; optical correlators for image recognition using volume holographic recording in photorefractive media; development of validation, encryption, and information encoding methods based on digital image processing techniques; study of speckle distribution recording in volumetric media (photorefractive crystals); speckle interferometry; digital speckle pattern interferometry (DSPI); and processing using optical vortices.

Within dynamic speckle techniques applied to biological tissue characterization and industrial processes, research at CIOp has addressed seed viability, fruit damage, parasite mobility, fungal detection, bacterial chemotaxis, paint drying processes, water adsorption in gels, foam evolution, among others. The atmospheric optics research line has been active at CIOp since before 2003.

These research lines have led to numerous international publications, conference contributions, and the training of human resources through the completion of doctoral theses.

Several of these works have been carried out in collaboration with research groups from universities in Rosario (IFIR), Salta, the central region of Buenos Aires Province (Tandil), CIDEPINT (La Plata), the Universities of Lavras and São Paulo (Brazil), the Pontifical Catholic University of Peru (Lima), the Universities of Antioquia and Pamplona (Colombia), the Autonomous University of Madrid (Spain), and the Polytechnic Institute of Havana (Cuba). In atmospheric optics, collaborations include the Pontifical Catholic University of Valparaíso and the University of the Andes (Chile).

Recent publications:

  • Dependence of the dielectric function of nanometric Au films on thickness. L. J. Mendoza Herrera, D. C. Schinca, L. B. Scaffardi, M. C. Tebaldi, Optica Pura y Aplicada, Vol. 57 – No. 1 (2024), Special Issue: RIAO OPTILAS 2023, Ref. 51164. DOI: http://dx.doi.org/10.7149/OPA.57.1.51164
  • Study of hygroscopic properties of the mixture of porous and non-porous materials by using optical techniques. R. D. Mojica Sepúlveda, L. J. Mendoza Herrera, M. Muñoz, E. E. Grumel, M. Tebaldi, Appl. Phys. B 130, 126 (2024). https://doi.org/10.1007/s00340-024-08263-4