Kabushiki Kaisha Toshiba

Varian Medical Systems, Inc.

Varex Imaging Corporation

Analogic Corporation

Bio-imaging Research, Inc.

Reed-chatwood, Inc.

Timothy R Fox

David T Nisius

Gongyin Chen

Jerry C Posluszny

Kevin Matthew Holt

Richard J Faehnrich

James Edward Clayton

Josh Star-Lack

Gary Fredric Virshup

Hans J Weedon

Richard E Colbeth

Bernard M Gordon

Kazuto Nakabayashi

John Fitzallen Moore

Daniel Shedlock

Paul Bjorkholm

Richard A Schewe

Iosif Izrailit

Robert Edward Drubka

Simon H Hughes

Douglas W Eaton

John Stammetti

Michael T Duncan

Michael Z Duncan

Martin Hu

Kevin Holt

Radiation scanning systems providing multiple views of an object in different planes and a reconstruction algorithm for reconstructing quasi-three-dimensional images from a limited number of views. A system may include bend magnets to direct accelerated charged particles to multiple targets in different viewing locations. Another system collimates radiation generated by a plurality of radiation sources into multiple beams for scanning an object at multiple angles. The object may be a cargo container, for example. The reconstruction algorithm uses an optimization algorithm and imaging and feasibility models to reconstruct quasi-three-dimensional images from the limited number of views.

Systems and methods for multi-view imaging and tomography

The present invention proposes a high speed radiographic system for use with megavolt linear-accelerator pulsed x-ray sources to produce video images of large-area fields. A linear accelerator is positioned above a field of view. X-ray photons are directed through an object of interest traveling and/or colliding within the field of view. A large area scintillator system, either truly continuous or in large continuous adjacent pieces, converts the x-ray photons that pass through the object into visible light, and an arrangement of cameras, focused at that plane, where each camera sees a sub-area of the entire scintillator, and these sub-areas overlap somewhat to cover the entire scintillator. The resulting images generated in each camera are synchronized to produce one contiguous, synchronized stream of images.

Systems and methods for high-speed radiography with high resolution imaging of large-area fields

A circuit to power an electron source includes a filament transformer comprising a primary side and a secondary side, a high-voltage transformer coupled to the filament transformer and the electron source, and an alternating current (AC) current limiter coupled in series with the primary side or the secondary side of the filament transformer. The AC current limiter includes a diode bridge and a current-limiting device in the diode bridge.

Soft-start adapter for AC heated electron gun

Methods and systems for scanning objects comprising scanning a portion of an object by a first radiation beam having a first value of a beam characteristic, such as the dose, and detecting the first radiation beam after interaction with the object by a first detector. It is determined whether to change the first value to a second value based, at least in part, on the detected first radiation beam. That portion of the object is then scanned by a second radiation beam having the first value or the second value based on the determination. The second radiation is detected after interacting with the object by a second detector. The second detector may have a second resolution greater than a first resolution of the first detector. The first and second radiation beams may be formed by first and second slots angled with respect to each other.

Feedback modulated radiation scanning systems and methods for reduced radiological footprint

A method for generating stabilized particle acceleration by a radio-frequency (RF) accelerator is described, comprising operating the accelerator in a warm-up mode during a warm-up time period, without injecting charged particles or without accelerating injected charged particles, and operating the accelerator in a beam-on mode during a beam-on time period after the warm-up time period, to accelerate charged particles injected by the charged particle source. Automatic frequency control to match an expected frequency of the accelerator during the beam-on time period, prior to the start of the beam-on time period, for stability, is also described.

Accelerator system stabilization for charged particle acceleration and radiation beam generation

An x-ray detector amplifier operably couples to an analog-to-digital converter interface and a switched voltage clamp is operably disposed there between. By one approach, the switched voltage clamp comprises a switched electrical connection to a constant potential (such as, but not limited to, ground). These teachings will accommodate a control circuit configured to control the switched voltage clamp. This can comprise, for example, controlling the switched voltage clamp in synchronicity with the pulsed x-ray source. These teachings will also accommodate an integrator operably connected between the x-ray detector amplifier and the analog-to-digital converter interface. In such a case, the switched voltage clamp and be controlled to remove substantially any voltage offset contribution of the x-ray detector amplifier (due, for example, to significant temperature excursions) to a signal that is integrated by the aforementioned integrator.

Method and apparatus pertaining to use of a switched voltage clamp with an x-ray detector amplifier

One facilitates capturing samples as pertain to an object to be imaged by providing N pulsed sampling chains (where N is an integer greater than 1) where these sampling chains are in planes substantially parallel to one another and are substantially equidistant from adjacent others by a given distance. By one approach, the ratio of this given distance to a desired sample interval is approximately an integer that is relatively prime to N. So configured, a complete set of samples of the object can be captured by the sampling chains in a single pass notwithstanding that the object and the sampling chains are moving quickly with respect to one another.

Apparatus to facilitate capturing samples as pertain to an object to be imaged and corresponding method

At least three radiation-detection views are used to facilitate identifying material as comprises an object being assessed along a beam path relative to that object. This comprises developing a first radiation-detection view () as corresponds to the material along the beam path, a second radiation-detection view () as corresponds to the material along substantially the beam path, and at least a third radiation-detection view () as corresponds to the material along substantially the beam path. At least one of the source spectra and detector spectral responses used for these radiation-detection views are different from one another for each view. One then uses () these radiation-detection views to identify the material by, at least in part, differentiating the material from other possible materials.

Method and apparatus to facilitate using multiple radiation-detection views to differentiate one material from another

A detector array is disposed relative to a radiation source such that radiation from the radiation source over a predetermined time period is substantially similar across the detector array. The detector array includes radiation detectors operatively coupled to detector electronics. The radiation filter material is disposed at least partially between the radiation source and the detector array such that different portions of the detector array are exposed to radiation from the radiation source through either different radiation filter material thicknesses or different radiation filter material compositions during the predetermined time period. So configured, information regarding the radiation such as beam quality information for radiation pulses is collected and used to confirm the quality of the radiation source or to adjust data collected by the radiation system.

Radiation system and radiation beam quality detector and method

A method and apparatus are provided for extending a dynamic range of an X-ray imaging system. The method includes the steps of detecting a plurality of X-ray beams, amplifying each of the plurality of detected X-ray beams using a first gain value, amplifying each of the plurality of detected X-ray beams using a second gain value, and forming an X-ray image from the detected X-ray beams amplified by the first gain value and from the detected X-ray beams amplified by the second gain value.

System for extending the dynamic gain of an X-ray detector

The disclosed dual energy baggage scanning assembly includes a CT scanning system, and a conveyor belt for transporting items through the CT scanning system, and an improved power supply for the X-ray source of the CT scanner so that a dual energy beam is provided. The power supply alternately powers the X-ray tube of the scanning system at high and low voltage levels at a predetermined rate and comprises at least one high voltage DC power supply for providing a stable, high DC voltage the X-ray tube; means, including at least one waveform generator, for providing a periodic time varying waveform; and coupling means, including a transformer, for coupling the waveform generator to said DC voltage supply so that the total voltage across the cathode and anode of the tube is periodically changed between the high and low voltage levels at the predetermined rate in response to the periodic time varying waveform provided by the waveform generator.

Dual energy power supply

A signal/noise ratio optimization tuning system, which can be used for tuning receiver antennas in Magnetic Resonance Imaging receiver systems, has a switch-controlled noise source means that is weakly coupled to the receiver antenna. The switch-controlled noise source switches a noise source between higher and lower power states at a predetermined frequency. A noise power meter means, which is synchronized to the switch-controlled noise source means, measures outputs of the receiver antenna. The noise power meter means measures the outputs of the receiver antenna when the noise source is switched between higher and lower power states and computes a ratio of the receiver antenna output with the noise source in the higher power state to the receiver antenna output with the noise source in the lower power state to obtain a noise power ratio. The tuning adjustment means is varied to maximize this noise power ratio.

Signal/noise ratio optimization tuning system

A carrier rejection circuit for improving carrier rejection in a balanced modulator includes balun transformers, connected to the carrier signal port and the modulated signal port, which reduces parasitic carrier leakage by reducing the average voltages at the ports, offset adjustment circuitry, connected to the modulating signal port, which applies an adjustable offset voltage to the modulating signal to reduce in-phase parasitic carrier leakage and carrier leakage caused by offset voltage at the modulating port, and a reactance network, connected between the carrier signal port and the modulated signal port, for reducing quadrature-phase parasitic carrier leakage.

Circuit for improving carrier rejection in a balanced modulator

A lowpass filter with improved D.C. offset characteristics is disclosed. The lowpass filter includes an adjustable amplifier, an offset detecting circuit for producing an offset signal proportional to the D.C. offset between the voltage from the adjustable amplifier and the voltage to the lowpass filter, and a feedback circuit for producing a feedback signal in response to the offset signal which controls the adjustable amplifier to reduce the D.C. offset.

Lowpass filter with improved D.C. offset performance

An MRI signal processing apparatus is disclosed which provides a low noise output signal for use in a multi-coil MRI system, wherein each sensing coil provides an input signal to the MRI signal processing apparatus. The apparatus includes input mixer circuitry for frequency shifting each input channel from a first frequency range to a second frequency range, controllable bandpass filter circuity connected to the input mixer circuitry for bandpass filtering each frequency shifted input channel to remove unwanted noise from the MRI signal, output mixer circuity for frequency shifting the output of the controllable bandpass filter circuitry from the second frequency range to the first frequency range, summing circuitry for combining the outputs of the output mixer circuitry of each channel to produce the low noise output signal, mixer control circuitry for controlling the frequency shift of the input mixer circuitry and the output mixer circuitry, and filter control circuitry for controlling the bandwidth and phase shift characteristics of the controllable bandpass filter circuitry.

Growing community of inventors

Chicago, IL, United States of America

Timothy R Fox