Electronics and Telecommunications Research Institute

Yoon Ho Song

Jin Woo Jeong

Jun Tae Kang

Jae Woo Kim

Dae Jun Kim

Jin Ho Lee

Kyoung Ik Cho

Chi Sun Hwang

Seung Youl Kang

Dong Il Kim

Kwang Yong Kang

Choong Heui Chung

Ji Seon Kim

Kwang Bok Kim

Do Hyung Kim

Yong Hae Kim

Hyun-Tak Kim

Seong Hyun Kim

Yong Suk Yang

Sang Chul Lim

Kwang-Yong Kang

Seong Deok Ahn

Byung Gyu Chae

Sung Yool Choi

Zin Sig Kim

Hyung Joun Yoo

Jae Hyun Moon

So Ra Park

Min Sik Shin

Young Rae Cho

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

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

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.

Tomosynthesis system

Provided is a pulse drive-type field emission device. The pulse drive-type field emission device includes anode and cathode substrates that are spaced apart from and face each other, a cathode electrode formed on the cathode substrate, and a field emitter formed on the cathode electrode. The pulse drive-type field emission device further includes a metal mesh-type gate electrode having an opening through which electrons emitted from the field emitter pass and a power source which applies a compensated pulse wave power to the gate electrode or the cathode electrode to compensate for vibration of the gate electrode. Thus, noise from the metal mesh can be prevented without additional fabrication processes by modifying a waveform in pulse driving.

Field emission device and driving method thereof

Disclosed is a field emitter, including: a cathode electrode in a shape of a tip; an emitter having a diameter smaller than a diameter of the cathode electrode and formed on the cathode electrode; and a gate electrode having a single hole and located above the emitter while maintaining a predetermined distance from the emitter.

Field emitter

Provided is a field emission device having a simple structure and capable of pulse driving and local dimming. The field emission device turns a current flowing from each cathode electrode block on or off in response to a switching control signal having a very low voltage ranging from 0 to 5 V while a constant voltage is applied to an anode electrode and a gate electrode to control a field emission current. Compared with a conventional field emission device, the field emission device having a simple structure is capable of pulse driving and local dimming without using a separate pulse driving high voltage power source.

Field emission device

A field emission pixel includes a cathode on which a field emitter emitting electrons is formed, an anode on which a phosphor absorbing electrons from the field emitter is formed, and a thin film transistor (TFT) having a source connected to a current source in response to a scan signal, a gate receiving a data signal, and a drain connected to the field emitter. The field emitter is made of carbon material such as diamond, diamond like carbon, carbon nanotube or carbon nanofiber. The cathode may include multiple field emitters, and the TFT may include multiple transistors having gates to which the same signal is applied, sources to which the same signal is applied, and drains respectively connected to the field emitters. An active layer of the TFT is made of a semiconductor film such as amorphous silicon, micro-crystalline silicon, polycrystalline silicon, wide-band gap material like ZnO, or an organic semiconductor.

Active-matrix field emission pixel

A microminiature X-ray tube with a triode structure using a nano emitter is provided, which can increase a field emission region as much as possible by means of nano emitters fine-patterned in a cathode to not only increase an emission current per unit area as much as possible but secure high electrical characteristics, reliability, and structural stability by means of a cover and a bonding material. In addition, gate holes having a macro structure can be formed in the gate to promote electron beam focusing by means of the gate without using a separate focusing electrode and to prevent a leakage current from occurring on the gate. Further, an auxiliary electrode can be formed on a top or an inner surface of a cover applied for structural stability to further promote the electron beam focusing and to control the output amounts per individual X-ray tubes output.

Microminiature X-ray tube with triode structure using a nano emitter

A field emission device having a simple structure and capable of readily changing emission colors of light by adjusting emission intensity of red, green and blue light is provided. In the field emission device, current that flows into each cathode electrode block is adjusted according to a very low control pulse signal of 0 to 5 V with a predetermined voltage applied to an anode electrode and a gate electrode over time, so that emission intensities of red, green and blue are individually adjusted. Therefore, the current that flows into each cathode electrode block is adjusted in a simple manner using a control pulse signal of a low level without a separate pulse driving high-voltage power supply, so that emission intensities of red, green and blue can be arbitrarily adjusted and emission colors of the field emission device can be readily changed.

Color variable field emission device

Provided is a field emission lamp (FEL), which includes a plurality of cathode electrodes formed above a first substrate, an anode electrode formed under a second substrate to face the cathode electrode, a fluorescent layer composed of red, green and blue (RGB) patterns formed alternately on the anode electrode in an oblique direction, and a plurality of emitters formed on the cathode electrodes to correspond to the RGB patterns. According to the present invention, as an FEL having a fast response time is used as a backlight unit, a color breaking phenomenon can be prevented in a color sequential driving method.

Growing community of inventors

Daejeon, South Korea

Yoon Ho Song