The most difficult task in near-field scanning optical microscopy (NSOM) is to make a high quality subwavelength aperture probe. Recently, we have developed high definition NSOM probes by focused ion beam (FIB) milling. These probes have a higher brightness, better polarization characteristics, better aperture definition and a flatter end face than conventional NSOM probes. We have determined t...

One-dimensional kinoform and prism refractive lenses with large aperture and high transmittance at 22 keV have been investigated. A 12.0 µm focus size (full width at half-maximum) and an effective aperture of 0.85 mm, at a focal length of 705 mm and 21.747 keV, were achieved.

Classical masking aperture methods are found to be mostly inaccurate to determine the terahertz beam size in terahertz time-domain spectroscopy (TDS) experiments, owing to complex diffraction effects. Here, we present a simple and reliable method for measuring beam waists in terahertz TDS. It is based on the successive diffraction by an opaque disk followed by a small circular aperture.

In this study, to predict the formation of free-fall arch via granular flow through an aperture, analytical model has been developed based on particle-scale force equilibrium. This calculates size and location meta-stable can be extended rate. According model, a is independent height stress state above arch, where only particle size, aperture friction influence development arch. Besides, propos...

Space-to-ground optical communication systems can benefit from reducing the size, weight, and power profiles of space terminals. One way of reducing the required power-aperture product on a space platform is to implement effective, but costly, single-aperture ground terminals with large collection areas. In contrast, we present a ground terminal receiver architecture in which many small less-ex...

Multiscale cameras achieve wide-angle, high-resolution imaging by combining coarse image formation by a simplified wide-field objective with localized aberration correction in an array of narrow field microcameras. Microcamera aperture size is a critical parameter in multiscale design; a larger aperture has greater capacity to correct aberration but requires a more complex microcamera optic. A ...

during 2012-2013 in a funistic survey of snails, several species of snails were collected and identified; both from orchards, farms and the weeds. in total, 18 species belonging to 17 genera out of 10 families are identified based on morphometric characteristics including (shape and size of operculum, aperture, dextral or sinistral of shell, pneumostome, keel, radula, renal ridge and reproducti...

An analytic explanation of the spatial resolution in thermoacoustic or photoacoustic reconstruction is presented. Three types of specific recording geometries, including spherical, planar, and cylindrical surface, as well as other general cases, are investigated. Analytic expressions of the point-spread functions (PSF's), as a function of the bandwidth of the measurement system and the finite s...