Multilevel Spiral Axicon for High-Order Bessel-Gauss Beams Generation.

This paper presents an efficient method to generate high-order Bessel-Gauss beams carrying orbital angular momentum (OAM) by using a thin and compact optical element such as a multilevel spiral axicon. This approach represents an excellent alternative for diffraction-free OAM beam generation instead of complex methods based on a doublet formed by a physical spiral phase plate and zero-order axicon, phase holograms loaded on spatial light modulators (SLMs), or the interferometric method. Here, we present the fabrication process for axicons with 16 and 32 levels, characterized by high mode conversion efficiency and good transmission for visible light (λ = 633 nm wavelength).

Automated imaging, identification, and counting of similar cells from digital hologram reconstructions.

This paper presents our method, which simultaneously combines automatic imaging, identification, and counting with the acquisition of morphological information for at least 1000 blood cells from several three-dimensional images of the same sample. We started with seeking parameters to differentiate between red blood cells that are similar but different with respect to their development stage, i.e.

Method of determination of light-scatterer distribution in edge-lit backlight units using an analytical approach.

We present a method to find the optimum distribution of scatterers in an edge-lit lightguide plate (LGP) for rendering a uniform distribution of the outcoupled light. We propose a simple mathematical model describing the light propagation in a waveguide with a distribution of scattering elements located on the lower surface of the waveguide. We have found a differential equation giving the distribution of scattering elements leading to a uniform irradiance along the LGP, and we propose a method to determine the value of the outcoupling coefficient of an individual scattering element from the irradiance (or radiance) measurements.