A collimator for an x-ray tube can be a monolithic, integral structure. The collimator can include a proximal-end closest to a cathode and a distal-end farthest from the cathode. The proximal-end can adjoin a vacuum inside of the x-ray tube. The distal-end can adjoin the air. The collimator can include an aperture extending therethrough. An x-ray window can be mounted across the aperture. The aperture can include a collimation-region between the x-ray window and the distal-end, and a drift-region between the x-ray window and the proximal-end. X-rays can be generated inside of the collimator.

X-ray target element is comprised of a planar wafer. The planar wafer element includes a target layer and a substrate layer. The target layer is comprised of an element having a relatively high atomic number and the substrate layer is comprised of diamond. The substrate layer is configured to support the target layer and facilitate transfer of thermal energy away from the target layer.

X-ray transparent insulation can be sandwiched between an x-ray window and a ground plate. The x-ray transparent insulation can include aluminum nitride, boron nitride, or polyetherimide. The x-ray transparent insulation can include a curved side. The x-ray transparent insulation can be transparent to x-rays and resistant to x-ray damage, and can have high thermal conductivity. An x-ray window can have high thermal conductivity, high electrical conductivity, high melting point, low cost, and matched coefficient of thermal conductivity with the anode. The x-ray window can be made of tungsten. For consistent x-ray spot size and location, a focusing plate and a filament can be attached to a cathode with an open channel of the focusing plate aligned with a longitudinal dimension of the filament. Tabs of the focusing plate bordering the open channel can be bent to align with a location of the filament.

An x-ray source includes an optical communications link to provide a galvanically isolated communication between a system controller and a gun controller. In specific examples, the link is provided through one or more fibers. In addition, the gun controller is preferably remote programmed by the system controller during startup. This addresses the problem of reprogramming a processor in a hard to access location/environment. A watchdog timer is also useful for the gun digital processor of the gun controller.

Embodiments of the present disclosure disclose a combined scanning X-ray generator, a composite inspection apparatus and an inspection method. The combined scanning X-ray generator includes: a housing; an anode arranged in the housing, the anode including a first end of the anode and a second end of the anode opposite the first end of the anode; a pencil beam radiation source arranged at the first end of the anode and configured to emit a pencil X-ray beam; and a fan beam radiation source arranged at the second end of the anode and configured to emit a fan X-ray beam; wherein the pencil beam radiation source and the fan beam radiation source are operated independently.

X-ray target element is comprised of a planar wafer. The planar wafer element includes a target layer and a substrate layer. The target layer is comprised of an element having a relatively high atomic number and the substrate layer is comprised of diamond. The substrate layer is configured to support the target layer and facilitate transfer of thermal energy away from the target layer.

A shield around an x-ray tube, a voltage multiplier, or both can improve the manufacturing process by allowing testing earlier in the process and by providing a holder for liquid potting material. The shield can also improve voltage standoff. A shielded x-ray tube can be electrically coupled to a shielded power supply.

A spark gap including a capacitive energy store is provided. The spark gap is fed via a multiplicity of capacitors arranged in a form of a ring, wherein the capacitors are electrically connected to the anode and the cathode via ring-shaped and conical or funnel-shaped conductors. As a result, sudden changes in impedance can be avoided. At the same time, it is possible to realize as large a cross-sectional area of the conductor as possible within a very small space. Therefore, the spark gap has a switching response with a high rate of rise of the voltage pulse as soon as the spark gaps flash over. This results in an easily predictable switching response of the spark gap. The spark gap can be used, for example, to generate pulses of monochromatic X-ray radiation.

Disclosed herein is an x-ray backscatter apparatus (“apparatus”) for non-destructive inspection of an object. The apparatus includes an x-ray emitter that includes a vacuum tube, an x-ray shield enclosed within the vacuum tube. The x-ray shield includes at least one emission aperture. The apparatus also includes a cathode enclosed within the vacuum tube and that is operable to generate an electron stream. Also included is an anode, enclosed within the vacuum tube and located relative to the cathode, to receive the electron stream and convert the electron stream from the cathode to an x-ray stream, and located relative to the emission aperture to direct at least a portion of the x-ray stream through the at least one emission aperture. Also disclosed are a system and a method that utilize the apparatus.

A transmission-target x-ray tube can include an x-ray window 12 mounted on a window-housing 13. The window-housing 13 can be made of a high density material with a high atomic number, and can include an aperture 13.sub.a with an increasing-inner-diameter region 23 for blocking x-rays and electrons.