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: The disclosure relates to a method for making field emission cathode. A microchannel plate is provided. The microchannel plate includes a first surface and a second surface opposite to the first surface. The microchannel plate defines a number of holes extending through the microchannel plate from the first surface to the second surface. The plurality of holes are filled with a carbon nanotube slurry. The carbon nanotube slurry is adhered on inner walls of the plurality of holes. The carbon nanotube slurry in the plurality of holes is solidified.

Abstract: An electron emission device includes an anode, a cathode, an electron emitter structure, and an electron extraction electrode. The cathode is spaced from the anode. The electron emitter structure is electrically connected to the cathode. The electron extraction electrode is insulated from the cathode. The electron extraction electrode defines a through hole surrounded by a sidewall, and the electron emitter structure faces to the sidewall. The electron emitter structure includes a number of electron emitters extending toward the sidewall, each of the number of electron emitters includes an electron emission terminal, a first distance between each electron emission terminal and the sidewall is substantially the same, a second distance between the electron emission terminal and the anode is greater than or equal to 10 micrometers and smaller than or equal to 200 micrometers, and a pressure in the electron emission device is smaller than or equal to 100 Pascal.

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 first electrodes and a number of second electrodes intersected with each other 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 and an insulating layer stacked together, the semiconductor layer defines a number of holes, the carbon nanotube layer covers the number of holes, and a portion of the carbon nanotube layer is suspended on the number of holes.

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: The disclosure relates to a field emission cathode. The field emission cathode includes a microchannel plate, a cathode electrode and a number of cathode emitters. The microchannel plate is an insulative plate and includes a first surface and a second surface opposite to the first surface. The microchannel plate defines a number of holes extending through the microchannel plate from the first surface to the second surface. The cathode electrode is located on the first surface. The number of cathode emitters are filled in the number of holes and electrically connected with the cathode electrode.

Abstract: The disclosure relates to a field emission cathode. The field emission cathode includes a microchannel plate, a cathode electrode and a number of cathode emitters. The microchannel plate is an insulative plate and includes a first surface and a second surface opposite to the first surface. The microchannel plate defines a number of holes extending through the microchannel plate from the first surface to the second surface. The cathode electrode is located on the first surface. The number of cathode emitters are filled in the number of holes and electrically connected with the cathode electrode.

Abstract: The disclosure relates to a field emission cathode. The field emission cathode includes a microchannel plate, a cathode electrode and a number of cathode emitters. The microchannel plate is an insulative plate and includes a first surface and a second surface opposite to the first surface. The microchannel plate defines a number of holes extending through the microchannel plate from the first surface to the second surface. The cathode electrode is located on the first surface. The number of cathode emitters are filled in the number of holes and electrically connected with the cathode electrode.

Abstract: The disclosure relates to a method for making field emission cathode. A microchannel plate is provided. The microchannel plate includes a first surface and a second surface opposite to the first surface. The microchannel plate defines a number of holes extending through the microchannel plate from the first surface to the second surface. The plurality of holes are filled with a carbon nanotube slurry. The carbon nanotube slurry is adhered on inner walls of the plurality of holes. The carbon nanotube slurry in the plurality of holes is solidified.

Abstract: An electron emission device includes an anode, a cathode, an electron emitter structure, and an electron extraction electrode. The cathode is spaced from the anode. The electron emitter structure is electrically connected to the cathode. The electron extraction electrode is insulated from the cathode. The electron extraction electrode defines a through hole surrounded by a sidewall, and the electron emitter structure faces to the sidewall. The electron emitter structure includes a number of electron emitters extending toward the sidewall, each of the number of electron emitters includes an electron emission terminal, a first distance between each electron emission terminal and the sidewall is substantially the same, a second distance between the electron emission terminal and the anode is greater than or equal to 10 micrometers and smaller than or equal to 200 micrometers, and a pressure in the electron emission device is smaller than or equal to 100 Pascal.

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 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 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: 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 electron collection layer, an insulating layer, and a second electrode stacked with each other, the electron collection layer is in contact with the semiconductor layer and the insulating layer, and the electron collection layer is a conductive layer.

Abstract: An electron emission device includes a number of electron emission units, wherein each of the number of electron emission units 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 having 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, the first electrodes in the number of electron emission units are spaced apart from each other, and the second electrodes in the number of electron emission units are spaced apart from each other.

Abstract: An electron emission device includes a number of first electrodes and a number of second electrodes intersected with each other 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 and an insulating layer stacked together, the semiconductor layer defines a number of holes, the carbon nanotube layer covers the number of holes, and a portion of the carbon nanotube layer is suspended on the number of holes.

Abstract: An electron emission source includes a first electrode, a semiconductor layer, an insulating layer, and a second electrode stacked in that sequence, wherein an electron collection layer is sandwiched between the semiconductor layer and the insulating layer, the electron collection layer is in contact with the semiconductor layer and the insulating layer, and the electron collection layer is a conductive layer to collect electrons.

Abstract: An electron emission device includes a number of second electrodes intersected with a number of first electrodes to define a number of intersections. The first electrode includes a carbon nanotube layer and a semiconductor layer coated on the carbon nanotube layer. An insulating layer is sandwiched between the first electrode and the second electrode at each of the number of intersections, wherein the semiconductor layer is sandwiched between the insulating layer and the carbon nanotube layer.

Abstract: An electron emission source includes a first electrode, a semiconductor layer, an insulating layer, and a second electrode stacked in that sequence, wherein the semiconductor layer defines a number of holes, the first electrode comprises a carbon nanotube layer, and a portion of the carbon nanotube layer corresponding to the number of holes is suspended on the number of holes.