Other

Cardiac Mariners, Inc.

Leland Stanford Junior University

Robert E Alvarez

Albert Macovski

Edward Gerald Solomon

Robert E Melen

Daniel J Rachlin

Bruno Strul

Augustus P Lowell

An apparatus or method for providing information about an object from x-ray radiation transmitted through the object. An embodiment comprises an x-ray source () positioned on one side of an object () an x-ray detector () positioned on the opposite side, and means for computing two or more information signals, which are substantially the line integrals of the basis set coefficients of the x-ray attenuation coefficient from the x-ray photons transmitted through said object at three or more regions of the x-ray energy spectrum. In one embodiment the means for computing the two or more information signals comprises a linear maximum likelihood estimator (), a correction processor () to compute a correction to the linear maximum likelihood estimate (), and an adder () to add the estimate and the correction to produce the two or more information signals ().

Energy selective X-ray system with low noise

An x-ray imaging system capable of local focussing to any depth is disclosed. According to an aspect, the invention comprises a method of generating a volume of data comprising image information for a plurality of depths with an object under investigation, and selecting data from the volume of data to generate a display image.

Image reconstruction for wide depth of field images

An image reconstruction system that can generate an accurate image representation of structure and regions within an object is disclosed. An aspect of the invention comprises a processor that is configured to receive x-ray transmissive information for an object to generate image pixel information for a plurality of depths within the object. The display image comprises selected image pixel information corresponding to image pixels at a plurality of depths within the object.

Image reconstruction method and apparatus

Multiple x-ray images are encoded onto a single storage phosphor screen detector for later scanning, processing, and viewing. The x-ray images are encoded using spatial frequency multiplexing onto high frequency carriers. The encoding process relies only on light with no mechanical motion. The light erases selected portions of the image data but leaves sufficient information to reconstruct the original images. The reconstruction process relies on conventional sampling theory with the additional step of solving a system of equations for the individual x-ray image information.

X-ray image encoding by spatial modulation of a storage phosphor screen

An apparatus and method for energy selective x-ray image detection. A source produces two fluxes of x-ray radiation with two different energy spectra. The fluxes are sequentially incident on the subject then on two layered planar detectors with control means. Examples of planar detectors are stimulable phosphor screens or intensifying screen/photographic film detectors. Examples of control means are visible light sources or electric generators with stimulable phosphor screens or light valves with intensifying screen/film detectors. A sequencer uses control means to selectively enhance the response of a predetermined detector to corresponding sequential radiation flux. The predetermined response can be chosen to enhance the inherent energy selectivity of the layered detector e.g. the first detector preferentially responds to low energy while the second detector preferentially responds to high energy x-ray photons. Planar detectors are used so that the layered detector fits in a cassette compatible with film cassettes used in medical radiography.

Active energy selective x-ray image detection

X-ray information is encoded onto photographic film by placing an optical grating between the light-emitting scintillating screen and the photographic emulsion. Information at different energies is encoded by displacing the grating between exposures or by using static gratings with an energy-selective dual screen.

X-Ray encoding system using an optical grating

Projection measurements are made of the transmitted x-ray beam in low and high energy regions. These are combined in a non-linear processor to produce atomic-number-dependent and density-dependent projection information. This information is used to provide cross-sectional images which are free of spectral-shift artifacts and completely define the specific material properties.

Growing community of inventors

Mountain View, CA, United States of America

Robert E Alvarez