Various methods and systems are provided for medical imaging systems. In one example, an imaging system comprises: a C-shaped gantry; an x-ray tube coupled to a first end of the C-shaped gantry; an x-ray detector coupled to a second end of the C-shaped gantry, opposite to the x-ray tube; and a controller with computer readable instructions stored on non-transitory memory that when executed, cause the controller to: identify a reference image; determine a target electrical current based on the reference image; determine a corrected electrical current based on the target electrical current; and transition an electrical current provided to the x-ray tube to the target electrical current by commanding the electrical current to the corrected electrical current while maintaining a constant voltage provided to the x-ray tube.

Disclosed is an electromagnetic wave generator, comprising a tube comprising an anode, a cathode and at least one gate, a tube power supply circuit in which one side of an output terminal is connected to the anode, and the other side of the output terminal is connected to the cathode, and a gate controlling circuit in which at least one side of the output terminal is connected to the gate, wherein a first voltage value of one side of the output terminal of the tube power supply circuit and a second voltage value of the other side of the output terminal of the tube power supply circuit are different from each other with respect to a ground terminal of the tube power supply circuit.

Disclosed is an electromagnetic wave generator, comprising a tube comprising an anode, a cathode and at least one gate, a tube power supply circuit in which one side of an output terminal is connected to the anode, and the other side of the output terminal is connected to the cathode, and a gate controlling circuit in which at least one side of the output terminal is connected to the gate, wherein a first voltage value of one side of the output terminal of the tube power supply circuit and a second voltage value of the other side of the output terminal of the tube power supply circuit are different from each other with respect to a ground terminal of the tube power supply circuit.

An x-ray tube assembly includes an x-ray tube with a vacuum envelope in which an emitter and an anode are arranged. The emitter is configured to be heated by an external coil emitter heating current supply. The emitter is configured as a flat emitter and an adaptation circuit is arranged between the flat emitter and the coil emitter heating current supply. A coil-emitter-based x-ray tube assembly may be replaced by a flat emitter-based x-ray tube assembly without constructional changes.

An x-ray tube assembly includes an x-ray tube with a vacuum envelope in which an emitter and an anode are arranged. The emitter is configured to be heated by an external coil emitter heating current supply. The emitter is configured as a flat emitter and an adaptation circuit is arranged between the flat emitter and the coil emitter heating current supply. A coil-emitter-based x-ray tube assembly may be replaced by a flat emitter-based x-ray tube assembly without constructional changes.

Provided is an X-ray generator including a thermal electron emission type X-ray generator configured to generate a negative high voltage and a filament current, a field electron emission type X-ray generator including an anode electrode to be grounded, and configured to use the negative high voltage to bias the cathode electrode, and a field emission current control unit configured to convert the filament current to generate an output voltage to be provided to a gate electrode of the field electron emission type X-ray generator and convert the filament current to fix, to a specific level, a level of an emission current flowing through the cathode electrode.

Provided is an X-ray generator including a thermal electron emission type X-ray generator configured to generate a negative high voltage and a filament current, a field electron emission type X-ray generator including an anode electrode to be grounded, and configured to use the negative high voltage to bias the cathode electrode, and a field emission current control unit configured to convert the filament current to generate an output voltage to be provided to a gate electrode of the field electron emission type X-ray generator and convert the filament current to fix, to a specific level, a level of an emission current flowing through the cathode electrode.

An X-ray tube assembly for generating an X-ray, comprises: a filament including a plurality of electric flow paths; and an adjustor configured to adjust at least one of values of current flowing through the plurality of electric flow paths to adjust an electron emission area of the filament.

An X-ray tube assembly for generating an X-ray, comprises: a filament including a plurality of electric flow paths; and an adjustor configured to adjust at least one of values of current flowing through the plurality of electric flow paths to adjust an electron emission area of the filament.

An x-ray system for simultaneously or concurrently measuring currents of multiple emitters is provided. The x-ray system includes a high voltage direct current (DC) supply configured to supply tube current to the multiple emitters and plural emitter circuits. Each of these circuits includes each comprising an alternating current (AC) voltage supply, at least one of the multiple emitters operatively coupled to the AC voltage supply and the high voltage DC supply, and a circuit coupling the AC voltage supply and the high voltage DC voltage supply to the at least one of the multiple filaments. At least one of the emitter circuits has a current measurement device between the high voltage DC supply and the emitter.