Electromagnetic wave generating device

Abstract

An electromagnetic wave generating device includes: a hollow annular vacuum chamber; an electron gun; an electromagnet configured with a pair of discoid combinations in which a cylindrical accelerating magnet pole and an annular focusing magnet pole are arranged in this order from the inner side to the outer side of the combinations, and are disposed symmetrically and concentrically with each other on both sides of the chamber and coaxially with the center axis of the chamber, and a return yoke disposed outside both accelerating and focusing magnet poles and the chamber; accelerating coils wound around the accelerating magnet poles, for exciting the poles; and focusing coils wound around the focusing magnet poles, for exciting the poles; wherein a through hole is formed at the center of the accelerating magnet pole so that power supply wires connecting the accelerating coils to an accelerating power supply are led out through the hole.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a horizontal sectional view illustrating an electromagnetic wave generating device according to Embodiment 1 of the invention;

FIG. 2 is a vertical sectional view illustrating the electromagnetic wave generating device according to Embodiment 1 of the present invention;

FIG. 3 is a configurational view illustrating magnet poles of the electromagnetic wave generating device according to Embodiment 1 of the invention;

FIG. 4 is an explanatory view illustrating a way to lead out the power supply wires of accelerating coils not according to the invention;

FIG. 5 is an explanatory view illustrating another way to lead out the power supply wires of accelerating coils not according to the invention;

FIG. 6 is an explanatory view illustrating another way to lead out the power supply wires of accelerating coils not according to the invention;

FIG. 7 is a view schematically illustrating magnetic flux according to Embodiment 1 of the invention;

FIG. 8 is a view schematically illustrating magnetic flux generated by accelerating coils with the power supply wires led out not according to the invention;

FIG. 9 is an equivalent circuit model showing the inductances of accelerating coils with the power supply wires pulled out not according to the invention;

FIG. 10 is a cross sectional view of the accelerating coils in the electromagnetic wave generating device according to Embodiment 1 of the invention; and

FIG. 11 is a cross sectional view of accelerating coils not according to the invention.

Claims

1. An electromagnetic wave generating device, comprising: a hollow annular vacuum chamber, the chamber being hermetically sealed to be kept under vacuum;an electron gun for emitting an electron beam into the vacuum chamber;an electromagnet including: a pair of discoid combinations each composed of a cylindrical accelerating magnet pole and an annular focusing magnet pole with a rectangular cross section, arranged in this order from the inner side to the outer side of the discoid combination, and disposed concentrically and symmetrically with each other on both sides of the vacuum chamber, and the center axis of the each discoid combination being made coaxial with that of the chamber; and a return yoke disposed outside around both the accelerating and focusing magnet poles, and the vacuum chamber;a pair of accelerating coils each wound around the accelerating magnet poles, for exciting the accelerating magnet poles;a pair of focusing coils each wound around the focusing magnet poles, for exciting the focusing magnet poles;a through hole formed along the center axis of the accelerating magnet poles; andpower supply wires led out through the through hole, to be connected to an accelerating power supply, for supplying electric power to the accelerating coils.

2. The electromagnetic wave generating device according to claim 1, wherein the through hole is formed in either one of the pair of accelerating magnet poles, and lead-in and lead-out power supply wires are led out through the through hole in common with each other.

3. The electromagnetic wave generating device according to claim 1, wherein one of the accelerating coils is wound radially from the inner side to the outer side of the one of the coils and the other coil is wound radially from the outer side to the inner side thereof, and the outer ends of the windings of both accelerating coils are connected with each other, and the inner ends of the windings of the accelerating coils are connected to the power supply wires.

4. The electromagnetic wave generating device according to claim 1, wherein the accelerating coil is wound from a wire having a rectangular cross section.

5. The electromagnetic wave generating device according to claim 1, wherein lead-in and lead-out power supply wires are twisted-pair wires that are twisted around each other.