General Electric Company

James A Blake

Jonathan Richard Schmidt

Steven D Hansen

James Zhengshe Liu

Robert F Senzig

Kishore Chandra Acharya

James R Dobbs

Richard Larry Anderton

Michael A Wu

Alexander M Blok

Jamie E Lazzaro

Sung Kwan Pyun

Alexander Meyer

The present disclosure presents systems and methods for correcting image artifacts on an x-ray image. X-ray images are obtained and processed with a correction algorithm that generates corrected pixel lines having pixels with corrected pixel values. The corrected pixel lines can then be processed with a filtering algorithm that generates filtered pixel line having pixels with a filtered pixel value. The bad pixel lines are replaced by the filtered pixel lines to generate corrected x-ray images.

Statistical property preserved bad line correction

The present invention, in one form, is an imaging system which synchronizes the emission of x-rays and the collection of data to a heart cycle to provide improved image quality. In one embodiment, the imaging system utilizes a synchronization unit to determine a selected heart period and to control generation of x-ray beams during the selected period. As the x-ray beams are emitted toward a detector, data is collected for a view angle. As the heart continues to cycle, data for a series of view angles is collected so that an image of the heart during the selected period is generated.

Cardiac gated computed tomography system

The present invention, in one form, includes methods and apparatus for reducing the x-ray dosage to a patient in a medical imaging system. In accordance with one embodiment of the present invention, a switching unit, or circuit, is coupled to a x-ray tube and a power supply to control the emission of x-ray beams from the x-ray tube. The switching unit is configured to alter a voltage and current signal applied to the x-ray tube control grid so that the magnitude of the x-ray beams is modified, or altered. By utilizing the switching unit the patient x-ray dosage is reduced and the magnitude of the x-ray beams may be configured to match the requirements of the application.

X-ray beam control for an imaging system

The present invention, in one form, is an imaging system which includes a verification system for verifying the proper connection of an interconnection cable. In accordance with one embodiment of the verification system, a verification circuit verifies operation of the interconnection cable by altering the patterns supplied from an EKG subsystem. More specifically, the conduction of interconnection cable is verified prior to, during and after scanning the patient by transmitting patterns received from the EKG subsystem through the verification circuit back to the EKG subsystem. If the patterns match the expected patterns, a verification signal is generated indicating proper cable connection.

Methods and apparatus for cable interconnection verification

An electric motor for an x-ray tube of a medical imaging system is described herein. The electric motor includes a stator and a substantially cylindrical rotor. The stator includes stator winding slots and stator windings injected into the stator winding slots. The stator also has a stator bore. The rotor is rotatably mounted within a stator bore so that the rotor is coaxial with the stator bore. The rotor includes a rotor core, a plurality of rotor bars, and end rings. The rotor bars are at located in rotor bar openings at a periphery of the rotor. At least one of the rotor bars has a different cross-sectional area than one of the other rotor bars.

Electric motor for an X-ray tube

A method is used for interfacing dissimilar materials in an X-ray tube. The X-ray tube includes a rotor assembly to distribute heat generated in the X-ray tube. The X-ray tube is sealed within a glass material which has a first expansion coefficient. An interface is provided between the rotor assembly and the glass material to absorb temperature coefficient stresses. Preferably, the glass material is Borosilicate and the interface comprises a metal material and a ceramic material. The ceramic material has a second expansion coefficient that closely matches the first expansion coefficient. The metal material is preferably Kovar, and the ceramic material is preferably Mullite. Temperature coefficient stresses are then absorbed within the ceramic and metal structure.

Glass to metal interface X-ray tube

An induction motor rotor particularly for x-ray tube applications comprises a series of hollow cylinders fitting concentrically on each other and on a motor shaft. The first cylinder is a highly heat resistant and electrically insulating material. The next cylinder is a highly magnetic material cylinder fitting on the first cylinder. The next and outermost cylinder is an electrically conductive material providing the armature conductor of the induction motor rotor.

X-ray tube target drive rotor

A rotating X-ray tube comprises a cathode assembly including a cathode and a cathode current supply, and an anode assembly having an anode current controlled via the cathode current supply. A filament for emitting electrons is separated from the cathode. A cathode cup supports the filament and provides electron field shaping assistance. The X-ray tube further comprises a distributed capacitance for affecting the cathode cup electron field, and an insulator leakage resistance. The cathode cup is allowed to float on the insulator leakage resistance, whereby voltage associated with the distributed capacitance and the leakage resistance is allowed to remain relatively constant.

X-ray tube

A supply for a high bias voltage in an X-ray imaging system has an inverter and a voltage multiplier that produce an alternating output voltage in response to control signals. A voltage sensor produces a signal indicating a magnitude of the output voltage. A circuit determines a difference between the sensor signal and a reference signal that specifies a desired magnitude for the output voltage and that difference is integrated to produce an error signal. The error signal preferably is summed with a precondition signal that is an approximation of a nominal value for the signal sum and the summation producing a resultant signal. Another summation device arithmetically combines the resultant signal and the sensor signal with a signal corresponding to a one-hundred percent duty cycle of the inverter operation in order to produce a duty cycle command. An inverter driver generates the inverter control signals that have frequencies defined by the resultant signal and have duty cycles defined by the duty cycle command. A unique state machine is described which generates those control signals.

High voltage power supply for an X-ray tube

A current supply has a first voltage summing circuit with two inputs, one of which receives a signal that indicates a desired current level to be produced. A current source produces a current level at an output in response to a control signal received from the first voltage summing circuit. The current source output is coupled to a center tap of the primary winding of a transformer that has a capacitor connected across the end terminals of its primary winding. Separate transistors connect ends of the primary winding to a common node and a resistor couples the node to circuit ground. A sensor produces a voltage e.sub.i that is proportional to a magnitude of the current flowing through said capacitor. A second voltage summing circuit produces an output voltage e.sub.t equivalent to the sum of voltage e.sub.i and the voltage across the resistor and the output voltage e.sub.t is applied to the other input of said first voltage summing circuit. Thus any change of the current from the source or of the current flowing through the capacitor alters the current flow in the primary winding in a manner that maintains the current in the secondary winding at a constant level.

Filament current regulator for an X-ray system

A X-ray emissive vacuum tube is fully enclosed in an electrically conductive casing with electrical terminals through which bias potentials are applied to the tube. Occasionally an arc discharge occurs between electrodes within the tube generating a high frequency signal which ordinarily resonates with the conventional casings. However a resistive coating is applied to the inner surface of the case. That coating has a resistivity sufficient to lower the Q of the case to a value at which significant ringing does not result from the discharge.

X-ray tube enclosure with resistive coating

An assembly for an X-ray imaging apparatus has a vacuum tube with an envelope containing an anode, a cathode and a filament. The vacuum tube is enclosed in an electrically conductive casing along with a high voltage supply for the tube. Electrical current is supplied to components within the casing by one or more transformers that extend through openings in the casing. Each transformer has an annular core that is sealed to the casing by magnetically non-conductive material. Another magnetically non-conductive seal extends across the central opening in the core. Thus each transformer is mounted in a manner that hermetically seals the aperture through which it extends. Each transformer has a one winding magnetically coupled to the core outside the casing, and another winding magnetically coupled to the core inside the casing and connected to an internal component of the assembly.

Growing community of inventors

Franklin, WI, United States of America

James A Blake