A radiation imaging apparatus includes: a processing unit configured to obtain a plurality of images corresponding to a plurality of different radiation energies by irradiating an object with radiation and performing imaging using an energy spectrum obtained by totaling energy information obtained by dividing a time-serially obtained radiation photon energy in a time direction, and perform energy subtraction processing using the plurality of images.

A radiation imaging apparatus includes: a processing unit configured to obtain a plurality of images corresponding to a plurality of different radiation energies by irradiating an object with radiation and performing imaging using an energy spectrum obtained by totaling energy information obtained by dividing a time-serially obtained radiation photon energy in a time direction, and perform energy subtraction processing using the plurality of images.

A system for protecting a transformer is provided. The system includes an inductor electrically disposed between the transformer and a load powered by the transformer, and a resistor electrically disposed in parallel with the inductor between the transformer and the load.

A system for protecting a transformer is provided. The system includes an inductor electrically disposed between the transformer and a load powered by the transformer, and a resistor electrically disposed in parallel with the inductor between the transformer and the load.

At least one power supply produces a voltage between a cathode and an anode. The cathode and anode are operable such that electrons emitted from the cathode interact with the anode with energies corresponding to the voltage. The electrons interact with the anode at a focal spot to generate X-rays. The power supply provides the cathode with a cathode current. An electron detector is positioned relative to the anode, and a backscatter electron signal is measured from the anode. The measured backscatter electron signal is provided to a processing unit, which determines a cathode current correction and/or a correction to the voltage between the cathode and the anode using the measured backscatter electron signal and a correlation between anode surface roughness and backscatter electron emission.

At least one power supply produces a voltage between a cathode and an anode. The cathode and anode are operable such that electrons emitted from the cathode interact with the anode with energies corresponding to the voltage. The electrons interact with the anode at a focal spot to generate X-rays. The power supply provides the cathode with a cathode current. An electron detector is positioned relative to the anode, and a backscatter electron signal is measured from the anode. The measured backscatter electron signal is provided to a processing unit, which determines a cathode current correction and/or a correction to the voltage between the cathode and the anode using the measured backscatter electron signal and a correlation between anode surface roughness and backscatter electron emission.

A method includes determining multiple X-ray tube current profiles of the X-ray tube, satisfying a loading limit of the X-ray tube; collecting first raw data of a patient according to the first X-ray tube current profile, with at least one X-ray tube current profile parameter of the first X-ray tube current profile being adapted according to a functional parameter; adapting the second X-ray tube current profile in the control unit such that, as a function of the at least one adapted X-ray tube current profile parameter, the second X-ray tube current profile satisfies the loading limit of the X-ray tube; collecting the second raw data of the patient according to the second X-ray tube current; reconstructing the medical image data set of the imaging measurement based upon the first raw data and the second raw data. Finally, the method includes provisioning the medical image data set.

The present invention discloses a stationary real-time CT imaging system, comprising an annular photon counting detector, an annular scanning x-ray source, and a scanning sequence controller. Under the control of the scanning sequence controller, the annular scanning x-ray source emits x-ray, and the x-ray penetrates the object being tested and projects onto the corresponding annular photon counting detector. The annular photon counting detector delivers the corresponding exposure information through the main scanning machine and the main controlling unit to a CT main machine and a human-machine interface unit. The image reconstruction is completed in the CT main machine and the human-machine interface unit. By electronically controlling and switching x-ray projection positions in order, the scanning speed is enhanced by tens of times, thereby obtaining dynamic 3D images. The use of the photon counting detector enables the access to absorption data and energy data, thereby allows for real-time data reconstruction.

The present invention discloses a stationary real-time CT imaging system, comprising an annular photon counting detector, an annular scanning x-ray source, and a scanning sequence controller. Under the control of the scanning sequence controller, the annular scanning x-ray source emits x-ray, and the x-ray penetrates the object being tested and projects onto the corresponding annular photon counting detector. The annular photon counting detector delivers the corresponding exposure information through the main scanning machine and the main controlling unit to a CT main machine and a human-machine interface unit. The image reconstruction is completed in the CT main machine and the human-machine interface unit. By electronically controlling and switching x-ray projection positions in order, the scanning speed is enhanced by tens of times, thereby obtaining dynamic 3D images. The use of the photon counting detector enables the access to absorption data and energy data, thereby allows for real-time data reconstruction.

A system for compensating for a back emission current in an X-ray generator is provided. The system includes a transformer, a common, and a voltage source. The transformer is operative to provide power to an electron emitter of the X-ray generator. The common is electrically coupled to an anode of the X-ray generator. The anode is operative to receive electrons emitted by the electron emitter such that the back emission current is generated between the common and the electron emitter. The voltage source electrically couples the common to the transformer and is operative to generate an offset voltage that reduces the back emission current.