JPS61194399A - Electron-ray projector - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an electron beam irradiation device that irradiates an object to be irradiated with an electron beam extracted from a linear cathode through a foil, and particularly relates to an improvement of the linear cathode. Regarding.

[Conventional technology]

FIG. 3 is a schematic sectional view showing an example of a conventional electron beam irradiation device, and FIG. 4 is a schematic perspective view showing an enlarged view of the area around the cathode in FIG. 3. A cylindrical shield electrode 3 with a high potential (negative high potential) is provided in a vacuum container 4 with a low potential, and inside the shield electrode 3, a plurality of linear cathodes 1 are lined up in the longitudinal direction. An electron beam E is extracted from the linear cathode 1 through an extraction grid 2 having the same potential as the shield electrode 3. The electron beam E is made of aluminum, titanium, etc., and the electron beam E is made of, for example, aluminum, titanium, etc.
A foil 6 that separates AS from the irradiation atmosphere side (for example, the atmosphere side)
Object to be irradiated on the irradiation atmosphere side As (not shown)
is irradiated.

[Problem that the invention seeks to solve]

The electron beam (beam) E extracted from the linear cathode 1 hits the foil 6 or the object to be irradiated with a width equal to the length of the short axis direction S of the linear cathode 1. Therefore, when increasing the electron beam current, even if the foil 6 is sufficiently wide in the short axis direction S, the net transmission width of the electron beam E depends on the length of the linear cathode 1. Heat loss due to loss is concentrated,
Eventually, the foil 6 will be damaged. Therefore, there is a problem that the electron beam current is limited by the foil 6 and cannot be increased to a large current.

Therefore, an object of the present invention is to provide an electron beam irradiation device that can disperse the electron beam density in the foil 6 and allow a large current.

[Means for solving problems]

In the electron beam irradiation device of the present invention, the linear cathode is curved in the electron beam extraction direction.

[Effect]

Because the linear cathode is curved in the electron beam extraction direction,
The electron beam is drawn out by spreading in the length direction of the linear cathode. This disperses the electron beam density in the foil, making it possible to tolerate large currents.

〔Example〕

FIG. 1 is a schematic cross-sectional view showing an example of the electron beam irradiation apparatus of the present invention, and FIG. 2 is a schematic perspective view showing an enlarged view of the area around the cathode in FIG. 1. Components equivalent to those in FIGS. 3 and 4 are designated by the same reference numerals and their explanations will be omitted.

In the electron beam irradiation apparatus of the present invention, a curved cathode 5 in which a linear cathode is curved in the direction in which the electron beam E is extracted is used. In this example, a plurality of curved cathodes 5
are arranged in parallel in the longitudinal direction within the shield electrode 3.

An electron beam E is drawn out from the curved cathode 5, spreading in the length direction of the cathode (ie, in the short axis direction S). Therefore, even if the curved cathode 5 has the same length in the short axis direction S as the linear cathode l of the conventional example, the electron beam E in the foil 6
Since the density of the foil 6 is dispersed, damage to the foil 6 due to heat loss is
This will not occur unless the electron beam current is made even larger. That is, according to the present invention, a larger current can be tolerated than in the conventional example. Furthermore, when compared with the same electron beam current, the life of the foil 6 is extended compared to the conventional example by the amount that the density of the electron beam is reduced.

〔Effect of the invention〕

As described above, according to the present invention, the thermal stress of the foil is alleviated by curving the linear cathode, so that a large electron beam current can be tolerated. Furthermore, it is possible to extend the life of the foil.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view showing an example of an electron beam irradiation device of the present invention. FIG. 2 is an enlarged schematic perspective view showing the area around the cathode in FIG. 1. FIG. 3 is a schematic cross-sectional view showing an example of a conventional electron beam irradiation device. Figure 4 shows the third
It is a schematic perspective view which expands and shows the cathode area of a figure. 5... Curved cathode, 6... Foil, As... Irradiation atmosphere side, E... Electron beam

Claims (1)

[Claims] (1) An electron beam irradiation device that irradiates an object to be irradiated with an electron beam drawn from a linear cathode through a foil, characterized in that the linear cathode is curved in the electron beam extraction direction.