PLASMA EXPANDER OF VARIABLE VOLUME Russian patent published in 2018 - IPC H05H1/34 

FIELD: technological processes.

SUBSTANCE: invention relates to plasma expander of variable volume and to devices for forming plasma for producing electron or ion beams. Variable-volume plasma expander has cylindrical shape, is made of conductive materials, plasma enters it through the hole in anode, on the other hand, there is a partial plasma limitation. Expander structure consists of 1 – cylindrical base, 2 – insert, made in the form of (A) ring, selectable from a set of rings with thickness of 5 to 30 mm in increments of 1 to 10 mm, bellows (B) or threaded connections (C), 3 – front, 4 – covers with emission hole and 5 – accessories for securing parts. Method for obtaining plane-parallel beam of charged particles involves use of specified plasma expander, in which plasma density is changed by controlling expander dimensions. In case of divergent beam from concave plasma boundary (Fig. 5C), an expander with shorter insert (2 in FIG. 6), reducing length and volume of expander, thereby increasing plasma density, and in case of divergent beam from plasma convex boundary (Fig. 5A), expander with longer insert (2 in FIG. 6), increasing expander length and reducing plasma density until plasma boundary is nearly flat.

EFFECT: technical result is simplification of tuning of beam formation system with simultaneous increase of its accuracy, which provides obtaining plane-parallel beam of charged particles.

6 cl, 6 dwg, 4 ex