Lawrence Livermore National Security, LLC

Iti Medical Technologies, Inc.

Roger W Werne

Stephen E Sampayan

Richard L Landingham

James S Sullivan

John Richardson Harris

A photoconductive semiconductor switch according to one embodiment includes a structure of sintered nanoparticles of a high band gap material exhibiting a lower electrical resistance when excited by light relative to an electrical resistance thereof when not exposed to the light. A method according to one embodiment includes creating a mixture comprising particles, at least one dopant, and at least one solvent; adding the mixture to a mold; forming a green structure in the mold; and sintering the green structure to form a transparent ceramic. Additional system, methods and products are also presented.

Transparent ceramic photo-optical semiconductor high power switches

This patent document discloses high voltage switches that include one or more electrically floating conductor layers that are isolated from one another in the dielectric medium between the top and bottom switch electrodes. The presence of the one or more electrically floating conductor layers between the top and bottom switch electrodes allow the dielectric medium between the top and bottom switch electrodes to exhibit a higher breakdown voltage than the breakdown voltage when the one or more electrically floating conductor layers are not present between the top and bottom switch electrodes. This increased breakdown voltage in the presence of one or more electrically floating conductor layers in a dielectric medium enables the switch to supply a higher voltage for various high voltage circuits and electric systems.

High voltage switches having one or more floating conductor layers

A medical interventional instrument for use in a magnetic resonance imaging (MRI) or other imaging system, a method for designing such an instrument, and a method including the steps of positioning an instrument having a body with a contrast region (constructed in accordance with the invention) and a target in the imaging region of an imaging system and operating the imaging system to produce an image showing both the target and the contrast agent. The instrument has a carbon-fiber or glass-fiber composite (or zirconia) body which preferably carries a contrast agent which is appropriate to the particular imaging modality to be used with the instrument. The concentration and volume of the contrast agent are determined (preferably experimentally) to cause the instrument to be positively shown in an image produced by the imaging system, without obscuring or distorting unacceptably the image of the target (e.g., a typical target, such as human tissue) with which the contrast agent is to be imaged. In some preferred embodiments, the contrast agent is a paramagnetic metal ion. In other preferred embodiments, the contrast agent is an iodinated hydrocarbon. In further preferred embodiments, the contrast agent is a preparation containing microbubbles of air or other gas, or the contrast region includes an air-filled void.

Fiber composite invasive medical instruments and methods for use in

A coated instrument for use in a magnetic resonance imaging (MRI) system, a method for designing such an instrument, and an MRI method including the steps of positioning a coated instrument (constructed in accordance with the invention) and a target in the imaging region of an MRI system, and operating the MRI system to produce an image showing both the target and the instrument. The instrument has a non-electrically conductive body covered by an electrically conductive, ultra-thin coating on at least part of the body. The thickness of the coating is determined (preferably experimentally) to be just large enough to cause the instrument to be positively shown in an MR image produced by the MRI system, but not so large as to obscure or distort unacceptably the image of a target (e.g., a typical target, such as human tissue, with which the instrument is to be imaged) in the same MR image (where both the instrument and target are in the MRI system's imaging region when the MRI system produces the MR image). The ultra-thin coating actually creates an imaging artifact which is sufficient to cause the instrument to be visible, but not so significant as to unacceptably distort the image of the intended target. In some preferred embodiments, the coating is a metal whose thickness is 2000 Angstroms or less. In other preferred embodiments, the coating is a metal whose thickness is of the same order of magnitude as its skin depth with respect to the radio frequency (RF) of the MRI system's RF field.

Growing community of inventors

San Ramon, CA, United States of America

Roger W Werne