Abstract: A single-photon absorption all-optical signal-processing device, systems employing the same, and methods of making and using the same. Illustrative examples are provided based on silicon semiconductor technology that employs rectangular waveguides fabricated on SOI wafers. In some embodiments, it is observed that the waveguides have surface state density, ?, of not less than 1.5×1018 cm?1s?1mW?1 to provide a single-photon absorption operation mode. In some embodiments, some portion of the ridge waveguide structure has a surface to volume ratio of at least 18 ?m?1, computed using a unit length of 1 ?m of the waveguide, with the width and depth dimensions of the waveguide being measured in units of microns.

Abstract: In addition to varying the luminance and chrominance levels of each voxel in an image, a viewing distance for objects within the image is varied to display a multi-focal, three-dimensional image. The focal distance of the voxels is determined by a depth map that indicates a fixation viewing depth of each object. When the image is viewed, there is a natural correspondence between the accommodation and vergence of the viewer's eye. The focal distance of the voxels displayed in the image are modulated using, for example, one or more dynamically variable focus mirrors or lenses, a plurality of fixed focus mirrors or lenses having different focal distances, a plurality of different length optical paths with different focal distance ranges, or at least one spatial light modulator. Light used to produce the image is scanned in two orthogonal directions either before or after the light is focus modulated.

Abstract: Strain is directly estimated in ultrasound elasticity imaging without computing displacement or resorting to spectral analysis. Conventional ultrasound elasticity imaging relies on calculating displacement and strain is computed from a derivative of the displacement. However, for typical parameter values used in ultrasound elasticity imaging, the displacement can be as large as a hundred times or displacement differences. If a tiny error in the calculation of displacement occurs, this could drastically affect the calculation of strain. By directly estimating strain, image quality is enhanced and the reduction in computational effort facilitates commercialization to aid in diagnosing disease or cancerous conditions.

Abstract: A system analyzes content accessed at a network site to determine whether it is malicious. The system employs a tool able to identify spyware that is piggy-backed on executable files (such as software downloads) and is able to detect “drive-by download” attacks that install software on the victim's computer when a page is rendered by a browser program. The tool uses a virtual machine (VM) to sandbox and analyze potentially malicious content. By installing and running executable files within a clean VM environment, commercial anti-spyware tools can be employed to determine whether a specific executable contains piggy-backed spyware. By visiting a Web page with an unmodified browser inside a clean VM environment, predefined “triggers,” such as the installation of a new library, or the creation of a new process, can be used to determine whether the page mounts a drive-by download attack.