Optica

El Manual práctico: optometría clínica es un documento orientado a dar asistencia durante el aprendizaje de la práctica clínica optométrica, con el objeto de mejorar la experiencia de formación profesional de los alumnos. La obra toma como eje la historia clínica, para guiar al lector en el proceso de atención en salud visual, resaltando sus conceptos fundamentales.

În această activitate manuală destul de intensă, elevii își fac propriile camere obscure dintr-un model dat în acest articol. Camera se poate construi dintr-o cutie de cereale din carton. Toate materialele sunt ușor disponibile, cu excepția, poate, a filmelor fotografice, pentru obținerea cărorava fi nevoie de un mic efort. Elevii vor învăța principiile fotografiei și se vor bucura de un nivel de creativitate care neîntâlnit în fotografia digitală.
O cameră obscură, care se poate face din materiale obișnuite și folosind film foto obișnuit, poate fi plasată oriunde și lăsată acolo timp de mai multe minute pentru a īnregistra toți fotonii care intră īn ea. La fel ca GALEX, poate fi plasată īn lumină slabă sau aproape īn īntuneric, și, dacă este lăsată deschisă suficient timp, va īnregistra prin impresie fotografică tot ce intră īn cāmpul ei vizual.
Discipline: fizică (optică), proiectare inginerească, astronomie
Activitate: proiect manual, care se poate lucra individual sau în grupuri mici de doi sau trei elevi, experimente teste.

We introduce single molecule light field microscopy (SMLFM), a novel 3D single molecule localization technique that is capable of up to 20 nm isotropic precision across a 6 μm depth of field. SMLFM can be readily implemented by installing a refractive microlens array into the conjugate back focal plane of any widefield single molecule localization system. We demonstrate that 3D localization can be performed by post-processing 2D localization data generated by common, widely-used, algorithms. In this work we benchmark the performance of SMLFM and finally showcase its capabilities by imaging fluorescently labeled membranes of fixed eukaryotic cells below the diffraction limit.

Films of transparent semiconductors are widely studied and developed because of high potential applications in electronics in last decade. Our work concerns the properties of NiO films fabricated by RF magnetron sputtering. Electrical and optical parameters of the films were characterized using Hall and transmittance measurements, respectively. P-type conductivity of as-deposited films and after annealing in oxygen or argon at the temperature range from 300 °C to 900 °C was verified. Transmittance of NiO films strongly depends on deposition temperature and oxygen amount during sputtering. Films deposited at room temperature without oxygen have transmittance near 50% in the visible range and resistivity about 65 Ωcm. An increase in oxygen amount in deposition gas mixture results in higher conductivity, but transmittance decreases below 6%. Resistivity of 0.125 Ωcm was attained at sputtering in oxygen. Films deposited at temperature elevated up to 500 °C are characterized by transmitt...

In this work, we evaluate the feasibility to determine the intraocular scattering by measuring the brightness reduction by glare. A haploscopic system based on the brightness comparison has been developed. This system allows to compare the brightness of a test with a steady ...

We fabricate an extremely thin optical fiber that supports a super-extended mode with a diameter as large as 13 times the optical wavelength, residing almost entirely outside the fiber and guided over thousands of wavelengths (5 mm), in order to couple guided light to warm atomic vapor. This unique configuration balances between strong confinement, as evident by saturation powers as low as tens of nW, and long interaction times with the thermal atoms, thereby enabling fast and coherent interactions. We demonstrate narrow coherent resonances (tens of MHz) of electromagnetically induced transparency for signals at the single-photon level and long relaxation times (10 ns) of atoms excited by the guided mode. The dimensions of the guided mode's evanescent field are compatible with the Rydberg blockade mechanism, making this platform particularly suitable for observing quantum non-linear optics phenomena.