An approach that uses an electro-optically tunable two dimensional phase grating to enhance the resolution in digital holographic microscopy is proposed. We show that, by means of a flexible hexagonal phase grating, it is possible to increase the numerical aperture of the imaging system, thus improving the spatial resolution of the images in two dimensions. The augment of the numerical aperture...

In this paper, we explain what are tensors and how tensors can help in computing.

The development of nanostructured metamaterials and the ability to engineer material dispersion has led to impressive advances in the diverse field of nanophotonics. Of interest to many is the enhanced ability to control, illuminate, and image with light on subwavelength scales. In this letter, we numerically demonstrate a hyperlens with unprecedented radial-resolution at 5 nm scale for both im...

CARS holography captures both the amplitude and the phase of a complex anti-Stokes field, and can perform three-dimensional imaging by digitally focusing onto different depths inside a specimen. The application of CARS holography for bio-imaging is demonstrated. It is shown that holographic CARS imaging of sub-cellular components in live HeLa cells can be achieved.

Hanna Neumann asked whether it was possible for two non-isomorphic residually nilpotent finitely generated (fg) groups, one of them free, to share the lower central sequence. G. Baumslag answered the question in the affirmative and thus gave rise to parafree groups. A group G is termed parafree of rank n if it is residually nilpotent and shares the same lower central sequence with a free group ...

Optical diffraction tomography is an imaging technique that permits retrieval of the map of permittivity of an object from its scattered far field. Most reconstruction procedures assume that single scattering is dominant so that the scattered far field is linearly linked to the permittivity. In this work, we present a nonlinear inversion method and apply it to complex three-dimensional samples....

We are developing three-dimensional imaging methods to portray vascular anatomy better, including noise-free display of vessels extracted from 3-D data sets, tree-based display, and reconstruction of angiographic data (preliminary work has resulted in the successful reconstruction of aneurysms from angiographic data). Fast, interactive display permits real-time manipulation of viewing orientation.

I present the theory of interferometric imaging (II). Interferometric imaging is any algorithm that images crosscorrelated data for the reflectivity or source distribution. As examples, I show that II can image arbitrary reflectivity distributions by migrating ghost reflections in passive seismic data, generalize the receiver-function imaging method used by seismologists, and migrate free-surfa...