A vacuum tube for amplifier circuit includes: a light incidence window that transmits signal light; a photoelectric conversion unit that converts the signal light transmitted through the light incidence window into photoelectrons; an output unit that has an anode, on which the photoelectrons are incident, and outputs a signal corresponding to the incident photoelectrons; and a grid electrode that is disposed in a path of the photoelectrons from the photoelectric conversion unit to the anode and controls the amount of photoelectrons incident on the anode.

A nano-vacuum tube (NVT) transistor comprising a source having a knife edge, a drain, and a channel formed between the source and the drain, the channel having a width to provide a pseudo-vacuum in a normal atmosphere. The NVT transistor utilizing a space charge plasma formed at the knife edge within the channel.

A nano-vacuum tube (NVT) transistor comprising a source having a knife edge, a drain, and a channel formed between the source and the drain, the channel having a width to provide a pseudo-vacuum in a normal atmosphere. The NVT transistor utilizing a space charge plasma formed at the knife edge within the channel.

A nano-vacuum tube (NVT) transistor comprising a source having a knife edge, a drain, and a channel formed between the source and the drain, the channel having a width to provide a pseudo-vacuum in a normal atmosphere. The NVT transistor utilizing a space charge plasma formed at the knife edge within the channel.

A vacuum tube for amplifier circuit includes: a light incidence window that transmits signal light; a photoelectric conversion unit that converts the signal light transmitted through the light incidence window into photoelectrons; an output unit that has an anode, on which the photoelectrons are incident, and outputs a signal corresponding to the incident photoelectrons; and a grid electrode that is disposed in a path of the photoelectrons from the photoelectric conversion unit to the anode and controls the amount of photoelectrons incident on the anode.

An X-ray generator is provided using a transmission type target having a long life span, where it is possible to change the point for generating X-rays on the surface of the target while maintaining the vacuum chamber in a high vacuum state. A portion of a vacuum chamber 1 that includes a target 2 is linked to a main body portion 1a of the chamber through a linking member 5 as a movable chamber portion 1b. A fixed anode 12 is provided between the target 2 and the electrode 10 at the final stage from among a group of electrodes 8, 9 and 10 for electrostatically accelerating and converging electrons from an electron source 7 and is fixed to the main body portion 1a of the chamber in order to prevent the form of the electrical field from changing when the movable chamber portion 1b is shifted.

An X-ray generator is provided using a transmission type target having a long life span, where it is possible to change the point for generating X-rays on the surface of the target while maintaining the vacuum chamber in a high vacuum state. A portion of a vacuum chamber 1 that includes a target 2 is linked to a main body portion 1a of the chamber through a linking member 5 as a movable chamber portion 1b. A fixed anode 12 is provided between the target 2 and the electrode 10 at the final stage from among a group of electrodes 8, 9 and 10 for electrostatically accelerating and converging electrons from an electron source 7 and is fixed to the main body portion 1a of the chamber in order to prevent the form of the electrical field from changing when the movable chamber portion 1b is shifted.