Electronics and Telecommunications Research Institute

Industry-University Cooperation Foundation Sunmoon University

Jin Woo Jeong

Yoon Ho Song

Jun Tae Kang

Dae Jun Kim

Jae Woo Kim

Yoon-Ho Song

Jae-Woo Kim

Sungyoul Choi

Dae Yong Kim

Sang Kuk Choi

Dong Il Kim

Kwang Yong Kang

Ho Seob Kim

Ji Seon Kim

Jin Ho Lee

Jeong Yong Choi

Juntae Kang

So Ra Park

Min Sik Shin

Provided herein is a field emission device. The field emission device includes a cathode which is connected to a negative power supply and emits electrons, an anode which is connected to a positive power supply and includes a target material receiving the electrons emitted from the cathode, and a ground electrode which is formed to face the anode and has an opening through which the electrons emitted from the cathode pass. The ground electrode is grounded so that when an arc discharge occurs due to high voltage operation of the anode, electric charge produced by the arc discharge is emitted to a ground.

Field emission device with ground electrode

The present disclosure may provide a micro X-ray tube with a filter tube to filter X-rays and at the same time to serve as an insulator. For this, the X-ray tube may include a filter tube between a second electrode and a gate electrode, hence separating from each other. The second electrode may have a target and the gate electrode may accelerate an electron-beam to collide with the target. The filter tube includes an alumina (AlO). The target is inclined to allow the X-rays to be directed toward the filter tube.

Micro X-ray tube

The present disclosure may provide a field emission device with an enhanced beam convergence. For this, the device may include a gate structure disposed between a cathode electrode and an anode electrode, wherein the gate structure includes a gate electrode and an atomic layer sheet disposed on the gate electrode, the gate electrode facing an emitter and having at least one aperture formed therein.

Field-emission device with improved beams-convergence

Disclosed is a field emitter electrode including a bonding unit formed on a substrate, and a plurality of carbon nanotubes fixed to the substrate by the bonding unit, in which the bonding unit includes a carbide-based first inorganic filler and a second inorganic filler formed of a metal.

Field emitter electrode and method of manufacturing the same

Provided are a field emission device and a method of manufacturing the same. The field emission device includes an anode electrode and a cathode electrode which are opposite to each other, a counter layer provided on the anode electrode, and a field emitter provided on the cathode electrode and facing the counter layer. Herein, the field emitter includes a carbon nanotube emitting cold electrons and a photoelectric material emitting photo electrons.

Field emission device having field emitter including photoelectric material and method of manufacturing the same

Provided is a method of driving multi electrical field emission devices. The method includes: respectively connecting first current control circuit devices for current path formation to a plurality of electric field emission devices; commonly connecting a second current control circuit device to the first current control circuit devices to commonly control the first current control circuit devices; and driving the first current control circuit devices at different timings when the second current control circuit device is driven.

Method for driving multi electric field emission devices and multi electric field emission system

Provided is an X-ray tube. The X-ray tube includes an electrode on which an electron beam impacts to generate an X-ray, and a window on which the electrode is disposed and through which the X-ray generated from the electrode is transmitted. The electrode includes a channel passing through the electrode, and the electron beam is provided into the channel to generate the X-ray.

X-ray tube having anode electrode

Provided is a current controlling device for controlling an electric field emission current in connection with an electric field emission device which emits electrons in response to an applied voltage, the device including: a first current controlling transistor forming a current path in response to a first gate voltage; a second current controlling transistor connected between the field emission device and the first current controlling transistor and forming a current path in response to a second gate voltage; and a control logic controlling the first and second gate voltages, wherein the control logic controls a upper limit of the field emission current by using the first gate voltage.

Current controlling device and electric field emission system including the same

Provided is a manufacturing method of a CNT emitter with density controlled CNT, comprising: (i) fabricating a CNT paste by dispersing a carbon nanotube (CNT) powder, two kinds or more of inorganic fillers which have a lower melting temperature than the CNT and different oxidation degrees of the CNT, and an organic binder in a solvent; (ii) coating the CNT paste on an electrode formed above a substrate; (iii) sintering the substrate coated with the CNT paste to selectively oxidize the CNT around one kind of inorganic filler among two kinds or more of the inorganic fillers; and (iv) treating the surface of the CNT paste so that the surface of the CNT paste is activated.

Manufacturing method of CNT emitter with density controlled carbon nanotube

An X-ray tube is provided. The X-ray tube includes a first housing including an X-ray window formed therein, a second housing being rotatable about a rotational shaft installed within the first housing, an anode installed on the rotational shaft within the second housing and positioned in one side of the rotational shaft in an extending direction of the rotational shaft, an emitter installed on the rotational shaft within the second housing, positioned in the other side of the rotational shaft in the extending direction of the rotational shaft, and emitting electron beams, a lens unit installed between the anode and the emitter and focusing the electron beams emitted from the emitter to the anode, and an electron beam deflection unit installed on the rotational shaft to deflect an angle of electron beams moving toward the anode from the lens unit.

X-ray tube

An X-ray tube is provided. The X-ray tube includes a cathode electrode which is disposed in one end of a vacuum container and includes an emitter emitting an electron; a gate electrode which is disposed in the vacuum container to be adjacent to the cathode electrode; an anode electrode which is disposed in the vacuum container of the other end of a direction in which the vacuum container extends and inclines with respect to the cathode electrode; and a focusing electrode which is disposed in the vacuum container along an inner circumference surface of the vacuum container between the gate electrode and the anode electrode. The focusing electrode has an opening of which a plan cross section has a maximum width and a minimum width different from each other.

X-ray tube and method of controlling X-ray focal spot using the same

The present disclosure relates to a stacked x-ray tube apparatus using a spacer, and more particularly, to a stacked x-ray tube apparatus using a spacer that makes it possible to reduce the size of an x-ray tube by forming a stacked structure, with electric insulation and predetermined gaps maintained for each electrode, by forming a stacked x-ray tube by inserting insulating spacers (for example, ceramic) between a exhausting port, a cathode, a gate, a focusing electrode, and an anode and bonding them with an adhesive substance, and then inserting a spacer between a field emitter on a cathode substrate and a gate hole connected with a gate electrode.

Stacked x-ray tube apparatus using spacer

The present disclosure relates to an electric field emission x-ray tube apparatus equipped with a built-in getter, and more particularly, to an electric field emission x-ray tube apparatus equipped with a built-in getter that makes it possible to reduce the size of an x-ray tube by forming a stacked structure, with electric insulation and predetermined gaps maintained for each electrode, by manufacturing an x-ray tube having a stacked structure by inserting insulating spacers (for example, ceramic) between an exhausting port, a cathode, a gate, a focusing electrode, and an anode and bonding them with an adhesive substance, and then inserting a spacer between a field emitter on a cathode substrate and a gate hole connected with a gate electrode.

Electric field emission x-ray tube apparatus equipped with a built-in getter

The present disclosure relates to a field emission X-ray tube apparatus for facilitating cathode replacement, and more particularly, to a field emission X-ray tube apparatus for facilitating cathode replacement in which gates and cathodes are easily arranged through a joining member and a rotation preventing guide when gates and insulating spacers are rotated and joined with the cathodes while the cathodes and respective gates maintain electrical insulation, thereby easily replacing the cathodes.

Field emission x-ray tube apparatus for facilitating cathode replacement

Disclosed is a tomosynthesis system in which the maintenance is easily performed. The tomosynthesis system of the present disclosure includes a vacuum chamber, a plurality of X-ray sources configured to be coupled to the vacuum chamber so as to protrude from the vacuum chamber to generate X-rays in a direction of a subject, and an image sensor configured to detect an X-ray projection image that passes through the subject.

Growing community of inventors

Daejeon, South Korea

Jin Woo Jeong