A method and a device for driving high-voltage X ray tube with positive and negative pulses are disclosed comprises a microprocessor unit having a first output port and a second output port, respectively outputting a first and a second timing sequence of control signals, a high-voltage X ray tube, a first high-frequency voltage boost circuit outputting a first regulated high-voltage, a first high-voltage protection circuit, a second high-frequency voltage boost circuit outputting a second high-voltage, and a second high-voltage protection circuit. The first high and the second voltages are respectively, regulated by the first timing sequence of control signal and the second timing sequence of control signal. Both regulated high-voltages are, respectively, inputted to anode and cathode of the high-voltage X ray tube vias the high-voltage protected circuits.

An open microfocus X-ray source and a control method thereof are provided. The open microfocus X-ray source includes: an open X-ray tube, a high voltage power supply (HVPS) system, a vacuum system and a control system. The open X-ray tube includes a cathode system, a deflection system and a focusing system. The HVPS system is configured to provide an emission current I.sub.0, an accelerating high voltage U.sub.0 and a grid voltage U.sub.G for an electron beam. The vacuum system is configured to perform vacuumization. The control system is configured to control, according to a spot size of an electron beam for bombarding an anode target, the HVPS system to adjust the emission current I.sub.0, the accelerating high voltage U.sub.0, a deflection coil current I.sub.XY of the deflection system, and a focusing coil current I.sub.F of the focusing system, such that the spot size meets a preset requirement.

A method and a device for driving high-voltage X ray tube with positive and negative pulses are disclosed comprises a microprocessor unit having a first output port and a second output port, respectively outputting a first and a second timing sequence of control signals, a high-voltage X ray tube, a first high-frequency voltage boost circuit outputting a first regulated high-voltage, a first high-voltage protection circuit, a second high-frequency voltage boost circuit outputting a second high-voltage, and a second high-voltage protection circuit. The first high and the second voltages are respectively, regulated by the first timing sequence of control signal and the second timing sequence of control signal. Both regulated high-voltages are, respectively, inputted to anode and cathode of the high-voltage X ray tube vias the high-voltage protected circuits.

The disclosed subject matter includes devices and methods relating to vacuums and vacuum assemblies. In some aspects, methods and devices relate to a vacuum assembly including a body defining an evacuated vacuum chamber, a conduit in the body extending between the vacuum chamber and an exterior of the body, a plug at least partially occluding the conduit, and a seal between the plug and the body that seals the vacuum chamber from the exterior of the body.

The X-ray tube disclosed herein includes an electron emission unit including an electron emission element using a cold cathode; an anode unit disposed opposite to the electron emission unit, with which electrons emitted from the electron emission unit collide; and a focus structure disposed between the electron emission unit and a target unit disposed on a surface of the anode unit that is opposed to the electron emission unit. The electron emission unit is divided into first and second regions which can independently be turned ON/OFF. The X-ray tube is focus-designed such that collision regions, at the anode unit, of electron beams emitted from the respective first and second regions substantially coincide with each other.

In the present invention, a pressure measurement device for determining the vacuum level within the evacuated housing of a vacuum electrode device is provided that includes an electrically conductive enclosure secured to an interior surface of the housing, an electrically conductive electrode extending through an aperture in the housing, the electrode having a tip at one end positioned within the interior of the housing inside the enclosure to define a gap between the tip and the enclosure and a conductive lead at a second end disposed outside of the housing, and a voltage source connected to the conductive lead to supply a voltage potential to the tip of the electrode. A voltage difference produced between the electrode and the enclosure ionizes gas within the enclosure causing a measurable current to flow between the electrode and the enclosure which can be used to determine the vacuum level in the housing.

An x-ray device utilizes a band of material to exchange charge through tribocharging within a chamber maintained at low fluid pressure. The charge is utilized to generate x-rays within the housing, which may pass through a window of the housing. Various contact rods may be used as part of the tribocharging process.

An x-ray device utilizes a band of material to exchange charge through tribocharging within a chamber maintained at low fluid pressure. The charge is utilized to generate x-rays within the housing, which may pass through a window of the housing. Various contact rods may be used as part of the tribocharging process.

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 tube is provided with: a cathode and an anode sealed inside a vacuum envelope; and an ion-collecting conductor attached to the vacuum envelop so as to be in contact with an internal space of the vacuum envelope. A first current sensor measures a value of a first current flowing between the ion-collecting conductor and a node for supplying potential for attracting positive ions in the vacuum envelope. A second current sensor measures a value of a second current flowing between the anode and the cathode. A control circuit generates diagnostic information on the degree of vacuum of the X-ray tube based on a current ratio file of the first current value measured by the first current sensor to the second current value measured by the second current sensor.