Gelaysi Moreno Vega

University of São Paulo | USP · Departamento de Oceanografia Física, Química e Geológica (Sao Paulo)

Understanding the dynamics of microbial plankton communities, their metabolic processes, and taxonomic composition in oligotrophic ocean basins has been one of the central tasks of contemporary marine microbial ecology and one of the main challenges in a changing global ocean. However, despite its ecological importance, the South Atlantic Subtropic...

The aim of the present work is to present an alternative way of using SLM in the experimental phase shifting setup to obtain a hologram by using only an illuminating beam. This beam is modified using a Spatial Light Modulator (SLM), where a number of selected SLM pixels generate a plane-illuminating wave with determinate phase, and other pixels gen...

In this paper the integral refractive index of a microscopic sample was directly measured by applying Digital Holographic Microscopy (DHM) capturing transmission and reflection holograms simultaneously, of the same sample's region, using Mach-Zehnder and Michelson micro interferometers for transmission and reflection holograms capture and modeling...

With the increased use of digital holography to observe biological events in three dimensions the need for autofocusing becomes essential. We introduced a modified image quality evaluation technique as a focus criterion in the reconstruction of digital holograms. The method employed was initially proposed by [Wang et al. (2008)] to evaluate image i...

The aim of this work was to correlate parameters of the metallurgical structure such as size and reorganizing the grains, as well as the hardening capacity and the samples distortion of AISI 1045 steel plastically deformed by roll and then fractioned, with average values root means square RMS of a Barkhausen Emission. The analyzed samples were defo...

In this paper the integral refractive index of a microscopic sample was directly measured by applying Digital Holographic Microscopy (DHM) capturing transmission and reflection holograms simultaneously, of the same sample's region, using Mach-Zehnder and Michelson micro interferometers for transmission and reflection holograms capture and modeling...

A digital holographic microscopy system configured by reflection (MHD-R) and illuminated by a laser diode was used to study the physical parameters of the surface of Fe-Si ferromagnetic steels. In such samples information was gathered using the image by phase contrast of the surface. Contour, grains dimensions and other irregularities of the materi...

A method for correcting the tilt and quadratic phase aberration of the reconstructed wavefield in digital holographic microscopy is proposed. The tilt aberration, induced by the tilt reference wave, is adjusted by calculating the coordinate origin of the hologram frequency domain and the quadratic phase aberration is compensated by calculate the cu...

A digital holographic microscopy system configured by reflection (MHD-R) and illuminated by a laser diode was used to study the physical parameters of the surface of Fe-Si ferromagnetic steels. In such samples information was gathered using the image by phase contrast of the surface. Contour, grains dimensions and other irregularities of the materi...

A method for correcting the tilt and quadratic phase aberration of the reconstructed wavefield in digital holographic microscopy is proposed. The tilt aberration, induced by the tilt reference wave, is adjusted by calculating the coordinate origin of the hologram frequency domain and the quadratic phase aberration is compen-sated by calculate the c...