A C-arm X-ray apparatus includes an x-ray emitter (5) and an X-ray detector (4) which are maintained on a C-arm (2) mounted on a reference plane. The x-ray emitter (5) has nanorods as electron emitters and has an elongated structure which is at least partially aligned along a surface normal of the reference plane.

In some embodiments, a cathode assembly may include a cathode head that has a first electron emitter and a second electron emitter. The first electron emitter may have a first connection location and a second connection location. The second electron emitter may have a third connection location and a fourth connection location. The third connection location may be electrically coupled with the second connection location of the first electron emitter. The cathode assembly may include a receptacle having a first connector and a second connector. The first connector may be electrically coupled with the first connection location of the first electron emitter. The second connector may be electrically coupled with the second connection location of the first electron emitter and the third connection location of the second electron emitter. The third connector may be electrically coupled with the fourth connection location of the second electron emitter.

One or more example embodiments relates to a system for calibration and/or for quality control of an FFS X-ray system, a corresponding FFS X-ray system, a control facility suitable for it and to a method for calibration and/or for quality control of the FFS X-ray system.

One or more example embodiments relates to a system for calibration and/or for quality control of an FFS X-ray system, a corresponding FFS X-ray system, a control facility suitable for it and to a method for calibration and/or for quality control of the FFS X-ray system.

Some example embodiments provide an x-ray tube for a stereoscopic imaging having an evacuated x-ray tube housing; an electron emitter apparatus in the x-ray tube housing, the electron emitter apparatus including a first field effect emitter with a first emitter surface and a second field effect emitter with a second emitter surface, at least one of the first emitter surface or the second emitter surface being segmented such that a portion of the at least one of the first emitter surface or the second emitter surface can be set relative to the respective overall emitter surface by selectively switching emitter segments of the at least one of the first emitter surface or the second emitter surface; an anode unit in the x-ray tube housing, the anode unit configured to generate x-ray radiation for the stereoscopic imaging as a function of electrons striking two focal points; and a control unit.

An emitter support structure for a field emission device, the emitter support structure includes: a support portion disposed to be moved in a direction of both ends of a vacuum chamber of the field emission device, and configured to support an emitter of the field emission device; a protruding portion formed at one end portion of the support portion which confronts a target of the field emission device, and to which the emitter is inserted and mounted; a slit formed in a circumference wall portion of the protruding portion in a height direction of the circumference wall portion; and a redundant brazing material groove formed in an outside of the protruding portion along the circumference wall portion.

Provided is an X-ray tube including a cathode structure, an anode spaced apart from the cathode structure, a spacer structure disposed between the cathode structure and the anode, and an external power supply connected to each of the cathode structure, the anode, and the spacer structure. Here, the spacer structure includes a first spacer disposed adjacent to the cathode structure and a second spacer disposed on the first spacer and disposed adjacent to the anode. The first spacer includes a first portion adjacent to the cathode structure and a second portion adjacent to a contact point of the first spacer and the second spacer. The second spacer includes a third portion adjacent to the contact point and a fourth portion adjacent to the anode. Each of the first portion and the third portion has a volume resistivity less than that of the second portion.

An emitter support structure for a field emission device, the emitter support structure includes: a support portion disposed to be moved in a direction of both ends of a vacuum chamber of the field emission device, and configured to support an emitter of the field emission device; a protruding portion formed at one end portion of the support portion which confronts a target of the field emission device, and to which the emitter is inserted and mounted; a slit formed in a circumference wall portion of the protruding portion in a height direction of the circumference wall portion; and a redundant brazing material groove formed in an outside of the protruding portion along the circumference wall portion.

Provided is an X-ray tube which includes a first electrode, a second electrode spaced apart from the first electrode, a target disposed in a lower portion of the second electrode, an emitter on the first electrode, a third electrode which is positioned between the first electrode and the second electrode and includes an opening at a position perpendicularly corresponding to the emitter, and a spacer provided on the third electrode and surrounding the second electrode. The spacer includes a first section located adjacent to the third electrode and a second section disposed on the first section. The spacer includes a ceramic insulator and conductive dopants dispersed within the ceramic insulator. A concentration of the conductive dopants in the first section of the spacer is greater than a concentration of the conductive dopants in the second section. The third electrode is in contact with the first section of the spacer.

A computer tomograph operates by rigidly arranged x-ray tubes, which are components of emitter-detector elements, which form an emitter-detector ring opened by relocating one emitter-detector element. Each x-ray tube includes a cathode emitting electrons, and an anode arrangement having an anode. Each cathode has an orientation angle relative to the geometrical center axis of the computer tomograph. A tangential plane on the focal spot of the anode has a surface normal, which includes an anode angle with the center axis. X-ray radiation emitted from the focal spot is directed in a center radiation angle to an x-ray detector axially offset relative to the x-ray tubes. The quotient from the sum of the orientation angle, radiation angle and anode angle is between two ninths and two. Each cathode, interacting with an electrode arrangement of the x-ray tubes, produces a focal spot on one of selectable positions on the anode arrangement.