Abstract: A carbon nanotube field emitter comprises at least two electrodes and at least one graphitized carbon nanotube structure. The at least one graphitized carbon nanotube structure comprises a first end and a field emission end. The first end is opposite to the field emission end. The first end is fixed between the at least two electrodes, and the field emission end is exposed from the at least two electrodes and configured to emit electrons.

Abstract: A field emission neutralizer is provided. The field emission neutralizer includes a bottom plate and a field emission cathode unit located on the bottom plate. The field emission cathode unit includes a substrate, a shell located on the substrate, a cathode emitter located inside the shell, a mesh grid insulated from the cathode emitter, and a shielding layer insulated from the mesh grid. The cathode emitter includes a cathode substrate and a graphitized carbon nanotube array. The graphitized carbon nanotube array is in electrical contact with the cathode substrate. The graphitized carbon nanotube array is fixed on a surface of the substrate body, and the carbon nanotubes of the graphitized carbon nanotube array are substantially perpendicular to the cathode substrate.

Abstract: A carbon nanotube field emitter comprises at least two electrodes and at least one graphitized carbon nanotube structure. The at least one graphitized carbon nanotube structure comprises a first end and a field emission end. The first end is opposite to the field emission end. The first end is fixed between the at least two electrodes, and the field emission end is exposed from the at least two electrodes and configured to emit electrons.

Abstract: A method for making a carbon nanotube field emitter is provided. A carbon nanotube film is dealed with a carbon nanotube film in a circumstance with a temperature ranged from 1400 to 1800° C. and a pressure ranged from 40 to 60 MPa to form at least one first carbon nanotube structure. The at least one first carbon nanotube structure is heated to graphitize the at least one first carbon nanotube structure to form at least one second carbon nanotube structure. At least two electrodes is welded to fix one end of the at least one second carbon nanotube structure between adjacent two electrodes to form a field emission preparation body. The field emission preparation body has a emission end. The emission end is bonded to form a carbon nanotube field emitter.

Abstract: A field emission neutralizer is provided. The field emission neutralizer includes a bottom plate and a field emission cathode unit located on the bottom plate. The field emission cathode unit includes a substrate, a shell located on the substrate, a cathode emitter located inside the shell, a mesh grid insulated from the cathode emitter, and a shielding layer insulated from the mesh grid. The cathode emitter includes a cathode substrate and a graphitized carbon nanotube array. The graphitized carbon nanotube array is in electrical contact with the cathode substrate. The graphitized carbon nanotube array is fixed on a surface of the substrate body, and the carbon nanotubes of the graphitized carbon nanotube array are substantially perpendicular to the cathode substrate.

Abstract: A method for making a carbon nanotube field emitter is provided. A carbon nanotube film is dealed with a carbon nanotube film in a circumstance with a temperature ranged from 1400 to 1800° C. and a pressure ranged from 40 to 60 MPa to form at least one first carbon nanotube structure. The at least one first carbon nanotube structure is heated to graphitize the at least one first carbon nanotube structure to form at least one second carbon nanotube structure. At least two electrodes is welded to fix one end of the at least one second carbon nanotube structure between adjacent two electrodes to form a field emission preparation body. The field emission preparation body has a emission end. The emission end is bonded to form a carbon nanotube field emitter.

Abstract: A method for making a carbon nanotube field emitter is provided. A carbon nanotube array and a cathode substrate are provided. The carbon nanotube array is heated to form a graphitized carbon nanotube array. A conductive adhesive layer is formed on a surface of the cathode substrate. One end of the graphitized carbon nanotube array is contact with the conductive adhesive layer. The conductive adhesive layer is solidified to fix the graphitized carbon nanotube array on the cathode substrate.

Abstract: A method for making a carbon nanotube field emitter is provided. At least one carbon nanotube wire and at least two electrodes are provided. The at least one carbon nanotube wire is heated to form at least one graphitized carbon nanotube wire. The at least one graphitized carbon nanotube wire comprises a first end and a second end, and the first end is opposite to the second end. The at least two electrodes are welded to fix the first end between the at least two electrodes. welding the at least two electrodes to fix the first end between the at least two electrodes. The second end of the at least one graphitized carbon nanotube wire is exposed from the at least two electrodes as an electron emission end.

Abstract: A field emission neutralizer is provided. The field emission neutralizer comprises a bottom plate and at least one field emission cathode unit located on the bottom plate. The field emission cathode unit comprises a substrate, a shell located on the substrate, a mesh grid, a shielding layer insulated and spaced from the mesh grid, and at least one cathode emitter located inside the shell, and insulated and spaced from the mesh grid. The cathode emitter comprises two cathode electrode sheets and a graphitized carbon nanotube structure, the graphitized carbon nanotube structure comprises a first portion and a second portion, the first portion is clamped between the two cathode electrode sheets, and the second portion is exposed outside of the two cathode electrode sheets.

Abstract: The disclosure relates to a battery testing apparatus. The battery testing apparatus includes a substrate and a body, the body is located on the substrate. The body includes a bottom, a central body and a cover, the bottom, the central and the cover is electrically insulated from each other. The substrate defines a first electrode point, a second electrode point and a third electrode point, the three electrode points are insulated from each other, the first electrode point is electrically connected with the central body, the second electrode point is electrically connected with the bottom, the third electrode point is electrically connected with the cover. The battery testing apparatus is configured to test electrochemical performance of a battery by a three-electrode method.

Abstract: The disclosure relates to a battery testing apparatus. The battery testing apparatus includes a substrate and a body, the body is located on the substrate. The body includes a bottom, a central body and a cover, the bottom, the central and the cover is electrically insulated from each other. The substrate defines a first electrode point, a second electrode point and a third electrode point, the three electrode points are insulated from each other, the first electrode point is electrically connected with the central body, the second electrode point is electrically connected with the bottom, the third electrode point is electrically connected with the cover. The battery testing apparatus is configured to test electrochemical performance of a battery by a three-electrode method.

Abstract: A heating pad includes a heating element, a number of first electrodes and a plurality of second electrodes. The heating element includes a flexible substrate and a carbon nanotube layer fixed on the flexible substrate. The heating element has a first end and a second end opposite to the first end. The first end is cut into a number of first strip structures. The second end is cut into a number of second strip structures. Each of the first electrodes clamps one of the first strip structures and is electrically connected with the first strip structure. Each of the second electrodes clamps one of the second strip structures and is electrically connected with the second strip structure.

Abstract: An apparatus for cutting micro-grids from a metal substrate is provided. The apparatus includes a support and a cutting module. The support includes a supporting surface, the support is configured to support a micro-grid and the metal substrate. The cutting module includes a fixing element, a spring and a cutting structure. The fixing structure and the spring are located in the cutting structure. The fixing element is configured to fix the micro-grid on the supporting surface. The cutting structure is configured to cut the micro-grid from the metal substrate.

Abstract: A field emission display includes a panel and a control unit. The panel has a number of pixel units. Each of the pixel units has at least one fluorescent layer. The control unit which electrically connects to the pixel units receives an objective image. The control unit further selects a part of the pixel units corresponding to the objective image, divides the part of the pixel units into a number of pixel unit groups, and scans the pixel unit groups to make the plurality of pixel unit groups sequentially work such that the panel displays the objective image.

Abstract: A method for making a heater is provided. A support and a flexible substrate are provided. The flexible substrate is stretched along a first direction and is fixed on a surface of the support. A carbon nanotube film is drawn from a carbon nanotube array. One end of the carbon nanotube film is attached on the flexible substrate. The carbon nanotube film is wrapped around the support by whirling the support to form a carbon nanotube layer. The flexible substrate is separated from the support and shrinks along the first direction. The carbon nanotube layer includes a plurality of carbon nanotubes aligned in the first direction. A plurality of electrodes are electrically connected with the carbon nanotube layer.

Abstract: A method for making a heater is provided. A support and a flexible substrate are provided. The flexible substrate is fixed on a surface of the support. A carbon nanotube film is drawn from a carbon nanotube array. One end of the carbon nanotube film is attached on the flexible substrate. The carbon nanotube film is wrapped around the support by whirling the support to form a carbon nanotube layer. The carbon nanotube layer includes a plurality of carbon nanotubes aligned in a first direction. The flexible substrate is heated to a temperature of about 80° C. to about 120° C. The flexible substrate is then shrunk along the first direction. A plurality of electrodes are electrically connected with the carbon nanotube layer.

Abstract: A method for making a heater is provided. A support and a flexible substrate are provided. The flexible substrate is stretched along a first direction and is fixed on a surface of the support. An adhesive layer is coated on a surface of the flexible substrate. One end of a carbon nanotube film is attached on the flexible substrate via the adhesive layer. The carbon nanotube film is wrapped around the support by whirling the support to form a carbon nanotube structure. The flexible substrate is separated from the support and shrinks along the first direction. At least two electrodes are electrically connected with the carbon nanotube structure. A voltage is applied between the at least two electrodes to heat the carbon nanotube structure. The carbon nanotube structure heats and solidifies the adhesive layer.

Abstract: A heater includes a heating element, a first electrode, a second electrode and a temperature controller. The heating element includes carbon nanotube layer and a binder. The carbon nanotube layer defines a number of wrinkles. The temperature controller is electrically connected to the heating element by the first electrode or the second electrode. The temperature controller is capable of controlling a temperature of the heating element by controlling a voltage and electric current applied to the heating element.