Abstract: Provided is a manufacturing apparatus for a carbon nanotube, including: at least two electrodes whose tips are opposed to each other, and a power supply that applies a voltage between the two electrodes to generate discharge plasma in a discharge area between the two electrodes. By using a porous carbonaceous material for at least one of the two electrodes, it is possible to provide a manufacturing apparatus and method for a carbon nanotube, which are capable of manufacturing at a low cost the carbon nanotube that is inexpensive and has a further higher purity.

Abstract: To provide an active electronic device which is formed from a carbon nanotube and which excels in high frequency operation and an electronic apparatus using the active electronic device. Provided are the active electronic device including: a carbon nanotube (1); a first electrode (S) connected to one end of the carbon nanotube; a second electrode (D) connected to the other end of the carbon nanotube; and a third electrode (G) facing the carbon nanotube (1) to irradiate the carbon nanotube (1) with electromagnetic waves, in which the amount of current flowing into the carbon nanotube (1) is changed by electromagnetic waves, at least high frequency electromagnetic waves, radiated from the third electrode onto the carbon nanotube (1), and the electronic apparatus using the active electronic device.

Abstract: An apparatus for manufacturing a carbon nanotube of the present invention includes: at least two electrodes whose tips oppose to each other; a power supply which applies a voltage between the electrodes so as to generate discharge plasma in a discharge area between the electrodes; a plurality of magnets which generates at least one of a magnetic field having lines of magnetic force in multiple directions or a magnetic field having a component in parallel with the direction of a discharge current in the generation area of the discharge plasma; and a magnet cooling unit which cools the magnets. The carbon nanotubes are manufactured by cooling the magnets. With this arrangement, there is provided a manufacturing apparatus and method for a carbon nanotube, which can efficiently synthesize carbon nanotubes with extremely low concentration of impurities on an industrial basis, and simultaneously can properly control especially the length of the obtained carbon nanotubes.

Abstract: A photoelectric conversion element comprising a substrate and a light sensor disposed on a surface of the substrate and receiving high speed optical pulse signals and converting them into high frequency waves in which the light sensor comprises at least carbon nano-tubes, as well as a photoelectric conversion device having the element, for directly converting high speed optical pulses signals in a communication band into signals of high frequency waves or electromagnetic waves.

Abstract: A photoelectric conversion element comprising a substrate and a light sensor disposed on a surface of the substrate and receiving high speed optical pulse signals and converting them into high frequency waves in which the light sensor comprises at least carbon nano-tubes, as well as a photoelectric conversion device having the element, for directly converting high speed optical pulses signals in a communication band into signals of high frequency waves or electromagnetic waves.

Abstract: Apparatus for producing a carbon structure at least including two electrodes 11 and 12 having forefront portions opposed to each other, and a power supply 18 for applying a voltage between the electrodes 11 and 12 so that discharge plasma is produced in a discharge area between the electrodes 11 and 12. The apparatus for producing a carbon structure further including a magnetic field generating unit 20 to 23 for forming at least a magnetic field including multidirectional lines of magnetic force or a magnetic field including a component parallel with the traveling direction of a discharge current, in an area where the discharge plasma is generated. In addition, a method for producing a carbon structure, using such an operation.

Abstract: The method of manufacturing carbon nanotubes and/or fullerenes reduces the pressure inside a system to 1.3 Pa or lower, supplies a carboniferous liquid state material to raise the pressure inside the system to at least 1.3 kPa to 93.3 kPa, generates arc discharges, supplies the carboniferous liquid state material in discharge plasma created by the arc discharges, and disintegrates or excites the carboniferous liquid state material, thereby producing the carbon nanotubes and/or the fullerenes. And, the manufacturing apparatus is equipped with at least a pair of electrodes that generate arc discharges into a vacuum chamber to create discharge plasma, a gas supply unit capable of supplying a carrier gas into the vacuum chamber, and a raw material supply unit capable of supplying a carboniferous liquid state material in the discharge plasma through an introduction tube.

Abstract: In an optical fiber comprising a core, and a clad which has a smaller refractive index than that of the core and with which the core is covered, an tip portion of the core has the most pointed portion which is in a conical form and has the top of an acute angle of .theta.1. Furthermore, the tip portion of the core has a core tip peripheral portion which is contiguous to the most pointed portion and has a slant of a gentler incline than the acute angle .theta.1. The optical fiber is used for, e.g., a probe.