Abstract: Provided is a field emission X-ray tube. The field emission X-ray tube includes a cathode electrode provided to one end of a vacuum vessel and including a field emission emitter, an anode electrode provided to the other end of the vacuum vessel in an extending direction of the vacuum vessel, and a gate electrode provided on an outer surface of the vacuum vessel adjacent to the cathode electrode.

Abstract: A discretely addressable large-area X-ray system is provided. The large-area X-ray system can output a uniform flux of X-rays over a large area using discrete addressing operation of transistors connected to cathodes of electron emitters. Thus, when applied to a medical device, the system can minimize damage inflicted upon the human body because it enables effective imaging of only a desired specific portion of the body. Furthermore, the large-area X-ray system can be simply implemented by current switching using transistors. Thus, the system can be very easily applied to other applications.

Abstract: 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.

Abstract: Provided is a field emission device (FED) capable of fine local dimming. In the FED, a cathode substrate is comprised of a plurality of cathode layers, and a plurality of interconnections are disposed on each of the cathode layers, so that fine local dimming is enabled using a plurality of cathode blocks without limiting the number of the cathode blocks. Also, since RC delays of the respective cathode blocks can be synchronized according to the design of the interconnections, current control signals can be simultaneously transmitted to the respective cathode blocks, thereby improving the characteristics of the FED.

Abstract: Provided is a field emission device, and more particularly, a field emission back light unit which makes an interconnection connected with an external electrode simple and capable of local dimming. To this end, a cathode structure for the field emission back light unit includes a plurality of data electrodes formed on a cathode substrate and spaced apart from one another, an insulating layer formed on the data electrodes, and having exposure regions exposing the predetermined data electrodes, cathode electrodes formed on the insulating layer and electrically connected with the data electrodes through the exposure regions, and at least one field emitter formed on the cathode electrodes, wherein a cathode block is defined based on the cathode electrodes electrically isolated from one another, and brightness of each cathode block can be controlled according to current supplied through the data electrode.

Abstract: Provided is a field emission display (FED) capable of driving on the basis of current and preventing leakage current caused by thin film transistors (TFTs). The FED includes: a plurality of unit pixels including an emission element in which cathode luminescence of a phosphor occurs and a TFT for driving the emission element; a current source for applying a scan signal to each unit pixel; and a voltage source for applying a data signal to each unit pixel. Here, the on-current of the current source is high enough to take care of the load resistance and capacitance of a scan row within a given writing time, and the off-current of the current source is so low that the electron emission of each pixel can be ignored. In addition, the pulse amplitude or pulse width of the data signal applied from the voltage source is changed, and thereby the gray scale of the display is represented.

Abstract: Disclosed is a field emission device. The field emission device includes: an anode substrate including an anode electrode formed on a surface thereof and a fluorescent layer formed on the anode electrode; a cathode substrate disposed opposite to and spaced apart from the anode substrate, and including at least one cathode electrode formed toward the anode substrate and a field emitter formed on each cathode electrode; and a gate substrate having one surface in contact with the cathode substrate, wherein the gate substrate include gate insulators surrounding the field emitters and having a plurality of openings exposing the field emitters, and a plurality of gate electrodes formed on the gate insulators around the openings and electrically isolated from one another.

Abstract: 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.

Abstract: 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 according to current switching to be equal to each other.

Abstract: Provided are a field emission device enabling rapid pulse operation and a method of operating the same. The field emission device includes a cathode electrode including a field emission source, an anode electrode disposed to face the cathode electrode and accelerating electrons emitted from the field emission source, a current controller controlling field emission current flowing through the cathode electrode, and a field emission controller applying a pull-up voltage to the cathode electrode when the current controller is turned off.

Abstract: An electron emission device having a high electron emitting rate and a display including the device are provided. The electron emission device using abrupt metal-insulator transition, the device including: a board; a metal-insulator transition (MIT) material layer disposed on the board and divided by a predetermined gap with portions of the divided MIT material layer facing one another; and electrodes connected to each of the portions of the divided metal-insulator transition material layer for emitting electrons to the gap between the portions of the divided metal-insulator transition material layer.

Abstract: A method of manufacturing a carbon nano-tube (CNT) emitter includes the steps of: (a) dispersing a CNT powder, an organic binder, a photosensitive material, a monomer, and a nano-sized metal particle in a solvent to manufacture a CNT paste; (b) coating the CNT paste onto an electrode formed over a substrate; (c) exposing the CNT paste coated on the electrode to thereby perform fine-patterning; (d) plasticizing the finely patterned CNT paste; and (e) processing a surface of the CNT paste such that the surface of the plasticized CNT paste is activated, wherein step (d) includes a first plasticizing step performed in an air atmosphere; and a second plasticizing step performed in a vacuum or inactive gas atmosphere. Improved uniformity of electron emissions in a field emission device is achieved and a plurality of CNT emitter regions are formed within a single pixel.

Abstract: Provided is a detector having a transistor or resistor structure. When an electrode is exposed to a detected solution, such as blood, a variation in current flowing through the detected solution may be greater than a variation in the electrical characteristics of the detector caused by a variation in the physical properties of semiconductor so that it is difficult to detect whether a bio-particle is contained in the detected solution. In order to solve this problem, a detection portion and an electrical measurement portion are separately formed, and the detection portion is processed with the bio-particle and then post-processed. Subsequently, the detection portion and the electrical measurement portion are bonded to each other using, for example, a laminating process, and the detector measures a detection value.

Abstract: A discretely addressable large-area X-ray system is provided. The large-area X-ray system can output a uniform flux of X-rays over a large area using discrete addressing operation of transistors connected to cathodes of electron emitters. Thus, when applied to a medical device, the system can minimize damage inflicted upon the human body because it enables effective imaging of only a desired specific portion of the body. Furthermore, the large-area X-ray system can be simply implemented by current switching using transistors. Thus, the system can be very easily applied to other applications.

Abstract: 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.

Abstract: Provided is a field emission device (FED) capable of fine local dimming. In the FED, a cathode substrate is comprised of a plurality of cathode layers, and a plurality of interconnections are disposed on each of the cathode layers, so that fine local dimming is enabled using a plurality of cathode blocks without limiting the number of the cathode blocks. Also, since RC delays of the respective cathode blocks can be synchronized according to the design of the interconnections, current control signals can be simultaneously transmitted to the respective cathode blocks, thereby improving the characteristics of the FED.

Abstract: Provided is a field emission device, and more particularly, a field emission back light unit which makes an interconnection connected with an external electrode simple and capable of local dimming. To this end, a cathode structure for the field emission back light unit includes a plurality of data electrodes formed on a cathode substrate and spaced apart from one another, an insulating layer formed on the data electrodes, and having exposure regions exposing the predetermined data electrodes, cathode electrodes formed on the insulating layer and electrically connected with the data electrodes through the exposure regions, and at least one field emitter formed on the cathode electrodes, wherein a cathode block is defined based on the cathode electrodes electrically isolated from one another, and brightness of each cathode block can be controlled according to current supplied through the data electrode.

Abstract: 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.

Abstract: 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.

Abstract: Provided is a field emission device. The field emission device includes an insulated cathode substrate facing an anode substrate, a plurality of cathodes arranged on the cathode substrate and separated from each other, and an emitter formed on each of the cathodes. In order to prevent accumulation of charges on an exposed area of the cathode substrate between the cathodes due to electrons discharged from the emitter, the distance between the cathodes is equal to or smaller than a first threshold value, and the distance from the emitter to the end of the cathode is equal to or greater than a second threshold value. Accordingly, in the field emission device in which a plurality of cathodes are separated from each other on the same plane, it is possible to prevent abnormal field emission and arc generation due to accumulated charges between the cathodes, thereby performing stable operation.