An electron emitting construct design of an x-ray emitter device is disclosed configured to facilitate radiation in the X-ray spectrum and further relates to preventing a cold cathode from being damaged by ion bombardment in high-voltage applications. The electron beam emitted by the emitting construct is focused and accelerated by an electrical field towards an electron anode target operable to attract electron beam to an associated focal spot, wherein the generated ions are accelerated along a trajectory perpendicular to the electric field in parallel to the surface of the electron anode target. More specifically, the present invention relates to realizing a robust cold cathode to avoid ion bombardments damages in high-voltage applications, by means of setting non-emitter zone surrounded by or set between the emitter areas. The system is further configured to provide an angled target anode or a stepped target anode to further reduce the ion bombardment damage.

The present disclosure provides a method of manufacturing a carbon nanotube electron emitter, including: forming a carbon nanotube film; performing densification by dipping the carbon nanotube film in a solvent; cutting an area of the carbon nanotube film into a pointed shape or a line shape; and fixing the cutting area of the carbon nanotube film arranged between at least two metal members to face upwards with lateral pressure.

A handheld X ray device comprises a camera-like X ray generator body having a zoom ring-like object at a front side of the X ray generator body as an exit of X rays and has a collimator section atop a surface of the zoom ring-like object. The camera-like X ray generator body inside has a voltage boosting circuit, an oscillator circuit, a battery, and a control circuit, and a user interface at a real panel of the camera-like X ray generator body. The glass ball-tube is a cold cathode type X-ray generator with a tungsten filament at a periphery of a cold cathode. The voltage boosting circuit, the oscillator circuit, boosting the voltage of the battery up to a predetermined high voltage under controlled of the control circuit assisting by the user interface.

An x-ray imaging system, such as a mobile radiography unit, includes a plurality of stationary carbon nanotube based x-ray sources to be selectively energized. A circuit enables a selected subset of the radiation sources to be energized while another subset may be disabled. A light source may be attached to the support arm of the mobile radiography unit and a source of electric power is configured to energize the light source upon operator contact with the unit. The plurality of stationary x-ray sources may be used to capture a plurality of 2-D projection images of a subject to reconstruct a 3-D image thereof. The 3-D image is used to generate a 2-D projection image of the subject.

The present invention relates to large area field emission devices based on the incorporation of macroscopic, microscopic, and nanoscopic field enhancement features and a designed forced current sharing matrix layer to enable a stable high-current density long-life field emission device. The present invention pertains to a wide range of field emission sources and is not limited to a specific field emission technology. The invention is described as an X-ray electron source but can be applied to any application requiring a high current density electron source.

An x-ray source for use in Phase Contrast Imaging is disclosed. In particular, the x-ray source includes a cathode array of individually controlled field-emission electron guns. The field emission guns include very small diameter tips capable of producing a narrow beam of electrons. Beams emitted from the cathode array are accelerated through an acceleration cavity and are directed to a transmission type anode, impinging on the anode to create a small spot size, typically less than five micrometers. The individually controllable electron guns can be selectively activated in patterns, which can be advantageously used in Phase Contrast Imaging.

Provided is an X-ray source including a vacuum closed tube. The X-ray source includes a high voltage connection module, a tube module, and a magnetic lens system into which the tube module is inserted. The tube module includes a vacuum closed tube. The vacuum closed tube includes a cathode electrode provided at one end thereof, a nano-emitter on the cathode electrode, an anode electrode provided at the other end, and a first insulation spacer provided between the cathode electrode and the anode electrode. In addition, the vacuum closed tube includes a first conductive tube and a second conductive tube both provided between the cathode electrode and the anode electrode and separated from each other by the first insulation spacer, and a first collimator block covering an inner surface of the first insulation spacer and having a first opening.

Described here is a method for performing phase contrast imaging using an array of independently controllable x-ray sources. The array of x-ray sources can be controlled to produce a distinct spatial pattern of x-ray radiation and thus can be used to encode phase contrast signals without the need for a coded aperture. The lack of coded aperture increases the flexibility of the imaging method. For instance, because a fixed, coded aperture is not required, the angular resolution of the imaging technique can be increased as compared to coded-aperture imaging. Moreover, the lack of a radioopaque coded aperture increases the photon flux that reaches the subject, thereby increasing the attainable signal-to-noise ratio.

The present disclosure is directed to an electron source and an X-ray source using the same. The electron source of the present invention comprises: at least two electron emission zones, each of which comprises a plurality of micro electron emission units, wherein the micro electron emission unit comprises: a base layer, an insulating layer on the base layer, a grid layer on the insulating layer, an opening in the grid layer, and an electron emitter that is fixed at the base layer and corresponds to a position of the opening, wherein the micro electron emission units in the same electron emission zone are electrically connected and simultaneously emit electrons or do not emit electrons at the same time, and wherein different electron emission zones are electrically partitioned.

Disclosed is a field emission apparatus. The apparatus comprises a cathode electrode and an anode electrode spaced apart from each other, an emitter on the cathode electrode, a gate electrode between the cathode and anode electrodes and including at least one gate aperture overlapping the emitter, and an electron transmissive sheet on the gate electrode and including a plurality of fine openings overlapping the gate aperture.