An x-ray generating unit includes an x-ray tube that is substantially transparent to x-rays. A cathode is within the x-ray tube and defines a plurality of spaced apart cavities. An anode includes a material that emits x-rays when impacted by electrons. A plurality of filaments is each disposed in a different one of the cavities. Each of the filaments is electrically coupled to each other and to an activating voltage source in parallel. Each of the filaments emits a focused electron beam directed to a different predetermined spot on the anode upon application of a predetermined voltage between the cathode and the anode, thereby causing the anode to generate x-rays. Each of the plurality of spaced apart cavities is aimed at the anode so that each predetermined spot on the anode is separated from each other spot by a gap that is not impacted by an electron beam.

A portable XRF analyzer includes a hand shield to substantially block x-rays from impinging on a hand of a user. The portable XRF analyzer includes a heat sink over an x-ray source and a heat sink over an x-ray detector. The heat sinks are separated from each other by a thermally insulative material.

An x-ray imaging device (10) comprising at least two substantially planar panels (20, 21), each panel comprising a plurality of x-ray emitters housed in a vacuum enclosure, wherein the at least two panels each have a central panel axis (28) and are arranged such that their central panel axes are non-parallel to one another, the device further comprising a panel retaining means and arranged such that the panel retaining means retains the at least two panels stationary in relation to an object during x-raying of the object.

Methods and means for reduced ng the overall diameter of an x-ray tube by recessing the vacuum pumping port stub within the ground plane of the x-ray tube without adversely affecting the electrostatic fields within the vacuum tube itself are provided. In one embodiment, x-ray tubes of smaller diameter, which can be used within the highly confined diameters typically found within the pressure housings of borehole tools are used.

Some embodiments include a structure, comprising: an insulator forming at least a part of a wall of a vacuum chamber, the insulator having a first end and a second end wider than the first end; a first conductive structure disposed at the first end of the insulator; and a second conductive structure disposed at the second end of the insulator, contacting the insulator, and including at least a portion surrounded by the insulator; wherein: a portion of an outer surface of the insulator extends radially outward from a triple junction between the insulator, the second conductive structure, and a medium contacting the outer surface of the insulator.

An X-ray tube according to the present invention comprises an anode and a cathode comprising an emission portion for emitting an electron beam. The emission portion is configured to irradiate a target surface of the anode with electrons to cause the anode to emit X-rays. A window is arranged at an end of the X-ray tube, to allow X-rays to exit the X-ray tube. The target surface of the anode is inclined at an oblique angle with respect to a longitudinal axis, wherein the longitudinal axis passes through the end of the X-ray tube.

Methods and means for reduced ng the overall diameter of an x-ray tube by recessing the vacuum pumping port stub within the ground plane of the x-ray tube without adversely affecting the electrostatic fields within the vacuum tube itself are provided. In one embodiment, x-ray tubes of smaller diameter, which can be used within the highly confined diameters typically found within the pressure housings of borehole tools are used.

An x-ray generating unit includes an x-ray tube that is substantially transparent to x-rays and that defines a vacuum therein. A cathode is disposed within the x-ray tube and defines a plurality of spaced apart cavities. An anode is spaced apart from the cathode and includes a material that emits x-rays when impacted by electrons. A plurality of filaments is each disposed in a different one of the cavities defined by the cathode and each is electrically coupled to the cathode. Each filament emits a focused electron beam directed to a different predetermined spot on the anode upon application of a predetermined voltage between the cathode and the anode, thereby causing the anode to generate x-rays.

An x-ray generating unit includes an x-ray tube that is substantially transparent to x-rays and that defines a vacuum therein. A cathode is disposed within the x-ray tube and defines a plurality of spaced apart cavities. An anode is spaced apart from the cathode and includes a material that emits x-rays when impacted by electrons. A plurality of filaments is each disposed in a different one of the cavities defined by the cathode and each is electrically coupled to the cathode. Each filament emits a focused electron beam directed to a different predetermined spot on the anode upon application of a predetermined voltage between the cathode and the anode, thereby causing the anode to generate x-rays.

An x-ray imaging device (10) comprising at least two substantially planar panels (20, 21), each panel comprising a plurality of x-ray emitters housed in a vacuum enclosure, wherein the at least two panels each have a central panel axis (28) and are arranged such that their central panel axes are non-parallel to one another, the device further comprising a panel retaining means and arranged such that the panel retaining means retains the at least two panels stationary in relation to an object during x-raying of the object.