Exploiting optical coherence tomography to evaluate wear in spiral dental polishing systems

Application of the Powell algorithm for estimating optical properties of a semitransparent medium based on time-domain information

Accurate estimation of the optical properties of a semitransparent medium is crucial in various engineering applications. This study introduces the Powell algorithm to estimate the optical properties of a 2D semitransparent slab. The time-domain radiative transfer equation is solved using the discrete ordinate method. The radiative intensity on the medium's surface serves as the measurement signal for the inverse analysis. The results demonstrate that the Powell algorithm accurately estimates the absorption coefficient, scattering coefficient, and scattering asymmetry factor. For simultaneous reconstruction of these three parameters, it is recommended to use eight signal detectors on both the left and right sides of the medium. Even when the standard measurement error is increased to 15%, the relative errors for these three parameters remain low, at 1.87%, 1.379%, and 0.194%.

Latin America Optics and Photonics 2022: introduction to the feature issue

The 2022 Latin America Optics and Photonics Conference (LAOP 2022), the major international conference sponsored by Optica in Latin America, returned to Recife, Pernambuco, Brazil, after its first edition in 2010. Held every two years since (except for 2020), LAOP has the explicit objective to promote Latin American excellence in optics and photonics research and support the regional community. In the 6th edition in 2022, it featured a comprehensive technical program with recognized experts in fields critical to Latin America, highly multidisciplinary, with themes from biophotonics to 2D materials. The 191 attendees of LAOP 2022 listened to five plenary speakers, 28 keynotes, 24 invited talks, and 128 presentations, including oral and posters.