Abstract: Some embodiments include a system, comprising: at least one x-ray source, each x-ray source including: an electron source configured to generate an electron beam; and a target configured to receive the electron beam and convert the electron beam into an x-ray beam; and a collimator. A first edge of the collimator closest to the electron source is closer to the electron source than a central axis of the x-ray beam before entering the collimator; and a second edge of the collimator opposite to the first edge is at the central axis of the x-ray beam before entering the collimator or closer to the electron source than the central axis of the x-ray beam before entering the collimator.

Abstract: Some embodiments include a system, comprising: a plurality of x-ray sources, each x-ray source including: an electron source configured to generate an electron beam; and a target configured to receive the electron beam and convert the electron beam into an x-ray beam; wherein: at first x-ray source of the x-ray sources is different from a second x-ray source of the x-ray sources; and the targets of the x-ray sources are part of a linear target.

Abstract: Some embodiments include an x-ray source, comprising: an anode; a field emitter configured to generate an electron beam; a first grid configured to control field emission from the field emitter; a second grid disposed between the first grid and the anode; a third grid disposed between the first grid and the anode; and a middle electrode disposed between the first grid and the anode wherein the second grid is either disposed between the first grid and middle electrode or between the middle electrode and the anode; wherein the third grid is a mesh grid.

Abstract: Some embodiments include an x-ray source, comprising: an anode; a field emitter configured to generate an electron beam; a first grid configured to control field emission from the field emitter; a second grid disposed between the first grid and the anode; and a middle electrode disposed between the first grid and the anode wherein the second grid is either disposed between the first grid and middle electrode or between the middle electrode and the anode.

Abstract: A system, comprising: a vacuum enclosure; an anode support structure penetrating the vacuum enclosure and including a plurality of first cooling passages; and an anode disposed within the vacuum enclosure, coupled to and supported by the anode support structure, and including: a target; and a plurality of second cooling passages; wherein: each of the second cooling passages is coupled to a corresponding first cooling passage; and the anode is coupled to the anode support structure on a side of the anode different from a side of the anode including the target and different from axial ends of the anode on a major axis of the anode

Abstract: Some embodiments include a system, comprising: a plurality of x-ray sources, each x-ray source including: an electron source configured to generate an electron beam; and a target configured to receive the electron beam and convert the electron beam into an x-ray beam; wherein: at first x-ray source of the x-ray sources is different from a second x-ray source of the x-ray sources; and the targets of the x-ray sources are part of a linear target.

Abstract: Some embodiments include an x-ray source, comprising: an anode; a field emitter configured to generate an electron beam; a first grid configured to control field emission from the field emitter; a second grid disposed between the first grid and the anode; and a middle electrode disposed between the first grid and the anode wherein the second grid is either disposed between the first grid and middle electrode or between the middle electrode and the anode.