Abstract: An electron emission device includes a number of second electrodes intersected with a number of first electrodes to define a number of intersections. An electron emission unit is sandwiched between the first electrode and the second electrode at each of the number of intersections, wherein the electron emission unit includes a semiconductor layer, an electron collection layer, and an insulating layer stacked together, and the electron collection layer is a conductive layer.

Abstract: An electron emission device includes a number of electron emission units spaced from each other, wherein each of the number of electron emission units includes a first electrode, a semiconductor layer, an insulating layer, and a second electrode stacked with each other, the first electrode includes a carbon nanotube layer, a number of holes defines in the semiconductor layer, and a portion of the carbon nanotube layer suspended on the number of holes.

Abstract: An electron emission source includes a first electrode, an insulating layer, and a second electrode stacked in that sequence, wherein the first electrode is a carbon nanotube composite structure comprising a carbon nanotube layer and a semiconductor layer stacked together, and the semiconductor layer is sandwiched between the carbon nanotube layer and the insulating layer. A method for making the electron emission source is also related.

Abstract: A method for making carbon nanotube slurry is presented. At least one carbon nanotube film is provided, the at least one carbon nanotube film includes a plurality of carbon nanotubes oriented along substantially the same direction. A substrate is provided, and the at least one carbon nanotube film is attached to a surface of the substrate. The at least one carbon nanotube film is cut perpendicular the oriented direction of the carbon nanotubes with a laser to form a carbon nanotube belt. An inorganic binder and an organic carrier is provided, the carbon nanotube belt, the inorganic binder, and the organic carrier are mixed in an organic solvent to form a mixture. The organic solvent is removed.

Abstract: The present disclosure provides a method for making carbon nanotube slurry. The method includes the following steps. First, a carbon nanotube array is provided on a substrate, the carbon nanotube array comprises a number of carbon nanotubes. Second, the carbon nanotube array is trimmed by a laser to obtain a trimmed carbon nanotube array comprising a plurality of trimmed carbon nanotubes having uniform lengths. Third, the trimmed carbon nanotube array is removed from the substrate to obtain the trimmed carbon nanotubes. Fourth, the trimmed carbon nanotubes are mixed with an inorganic binder and an organic carrier to obtain the carbon nanotube slurry.

Abstract: An X-ray tube includes a vacuum tube. A field emission cathode structure and an anode spaced from each other are located in the vacuum tube. The field emission cathode structure includes a first metal plate, a second metal plate, and an electron emitter. The electron emitter is fixed between the first metal plate and the second metal plate. One end of the electron emitter extends out of the first metal plate and the second metal plate to act as an electron emission end.

Abstract: A thermochromatic device in a thermochromatic display includes an insulating substrate, a color element, a heating element, a first electrode, and a second electrode, the color element and the heating element located on the insulating substrate being virtually integral but together are physically isolated and heat-insulated and allow such fast electrically-governed color changes that moving color images can be displayed.

Abstract: A field emission cathode device includes a cathode electrode. An electron emitter is electrically connected to the cathode electrode, wherein the electron emitter includes a number of sub-electron emitters. An electron extracting electrode is spaced from the cathode electrode by a dielectric layer, wherein the electron extracting electrode defines a through-hole. The distances between an end of each of the sub-electron emitters away from the cathode electrode and a sidewall of the through-hole are substantially equal.

Abstract: A thermochromatic device includes an insulating substrate, a color element, a heating element, a first electrode, and a second electrode. The color element is located on the insulating substrate and includes a reversible thermochromatic material. The heating element is located adjacent to the color element and includes a carbon nanotube structure. The first electrode and the second electrode are electrically connected to the heating element. A thermochromatic display apparatus using the thermochromatic device is also related.

Abstract: A method for making carbon nanotube field emitter includes providing a carbon nanotube array formed on a surface of a substrate. A plurality of carbon nanotubes of the carbon nanotube array is selected and pulled out a carbon nanotube film by a drawing tool, wherein the carbon nanotube film includes a plurality of carbon nanotubes oriented along a fixed direction. The carbon nanotube film is cut to a plurality of uniform carbon nanotube sub-films along the fixed direction. The plurality of carbon nanotube sub-films is treated to a plurality of carbon nanotube yarns. The plurality of carbon nanotube yarns is fixed on a surface of a conductive base, and cutting off the plurality of carbon nanotube yarns by a laser beam, to form a carbon nanotube field emitter.

Abstract: The present disclosure provides a field emission device. The field emission device includes an insulating substrate having a first surface, a first electrode, a second electrode, at least one cathode emitter and a secondary electron emitter. The first electrode and the second electrode are spaced from each other and are located on the first surface of the insulating substrate. The cathode emitter is electrically connected to the first electrode and spaced from the second electrode. A secondary electron emitter is spaced from the cathode emitter. The secondary electron emitter has an electron emitting surface exposed to the cathode emitter. A secondary electron emitter is spaced from the cathode emitter. The cathode emitter is oriented toward the secondary electron emitter.

Abstract: An ionization vacuum gauge includes a cathode, an anode and an ion collector. The ion collector component is located at one side of the anode component and spaced from the anode component. The cathode component is located at another side of the anode component and includes an electron emitter, which extends toward the anode component from the cathode component. The electron emitter includes at least one carbon nanotube wire.

Abstract: A method for forming a tip for a carbon nanotube wire is introduced. The method includes the following steps. A carbon nanotube wire is provided. A laser beam irradiates the carbon nanotube wire until the carbon nanotube wire is broken off such that the carbon nanotube wire forms a taper-shaped tip. A scan power of the laser beam is in a range from about 1 watt to about 10 watts. A scan speed of the laser beam is equal to or less than 200 millimeters per second.

Abstract: The present disclosure provides a method for making carbon nanotube slurry. The method includes the following steps. First, a carbon nanotube array is provided on a substrate, the carbon nanotube array comprises a number of carbon nanotubes. Second, the carbon nanotube array is trimmed by a laser to obtain a trimmed carbon nanotube array comprising a plurality of trimmed carbon nanotubes having uniform lengths. Third, the trimmed carbon nanotube array is removed from the substrate to obtain the trimmed carbon nanotubes. Fourth, the trimmed carbon nanotubes are mixed with an inorganic binder and an organic carrier to obtain the carbon nanotube slurry.

Abstract: A method for making carbon nanotube slurry is presented. At least one carbon nanotube film is provided, the at least one carbon nanotube film includes a plurality of carbon nanotubes oriented along substantially the same direction. A substrate is provided, and the at least one carbon nanotube film is attached to a surface of the substrate. The at least one carbon nanotube film is cut perpendicular the oriented direction of the carbon nanotubes with a laser to form a carbon nanotube belt. An inorganic binder and an organic carrier is provided, the carbon nanotube belt, the inorganic binder, and the organic carrier are mixed in an organic solvent to form a mixture. The organic solvent is removed.

Abstract: A field emission device includes a cathode, an anode, an emitter, a first adjusting electrode, and a second adjusting electrode. The emitter electrically connects to the cathode. The cathode, the first adjusting electrode, and the second adjusting electrode electrically connect to an electrode down-lead. The anode electrically connects another electrode down-lead. The cathode is disposed between the first adjusting electrode and the second adjusting electrode.

Abstract: An ion source using a field emission device is provided. The field emission device includes an insulative substrate, an electron pulling electrode, a secondary electron emission layer, a first dielectric layer, a cathode electrode, and an electron emission layer. The electron pulling electrode is located on a surface of the insulative substrate. The secondary electron emission layer is located on a surface of the electron pulling electrode. The cathode electrode is located apart from the electron pulling electrode by the first dielectric layer. The cathode electrode has a surface oriented to the electron pulling electrode and defines a first opening as an electron output portion. The electron emission layer is located on the surface of the cathode electrode and oriented to the electron pulling electrode.

Abstract: A method for making a field emission device includes the following steps. An insulative substrate is provided. An electron pulling electrode is formed on the insulative substrate. A secondary electron emission layer is formed on the electron pulling electrode. A first dielectric layer is fabricated. The first dielectric layer has a second opening to expose the secondary electron emission layer. A cathode plate having an electron output portion is provided. An electron emission layer is formed on part surface of the cathode plate. The cathode plate is placed on the first dielectric layer. The electron output portion and the second opening have at least one part overlapped, and at least one part of the electron emission layer is oriented to the secondary electron emission layer via the second opening.

Abstract: A thermal-chromatic element includes a sealed enclosure, an isolation layer, a first heating element, a thermal-chromatic material layer, a second heating element and an absorption material layer. The isolation layer is disposed in the sealed enclosure and separates the sealed enclosure into a first chamber and a second chamber. The first heating element is configured to heat thermal-chromatic material layer in the first chamber. The thermal-chromatic material layer is disposed in the first chamber. The thermal-chromatic material layer is able to change color by releasing and absorbing water. The second heating element is configured to heat absorption material layer in the second chamber. The absorption material layer is disposed in the second chamber.

Abstract: A field emission device includes an insulative substrate, an electron pulling electrode, a secondary electron emission layer, a first dielectric layer, a cathode electrode, and an electron emission layer. The electron pulling electrode is located on a surface of the insulative substrate. The secondary electron emission layer is located on a surface of the electron pulling electrode. The cathode electrode is located apart from the electron pulling electrode by the first dielectric layer. The cathode electrode has a surface oriented to the electron pulling electrode and defines a first opening as an electron output portion. The electron emission layer is located on the surface of the cathode electrode and oriented to the electron pulling electrode.