The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 24, 1996
Filed:
Feb. 21, 1995
Dominique Valentian, Rosny, FR;
Societe Europeenne de Propulsion, Suresnes, FR;
Abstract
The present invention relates to an ion-optical system for a gas-discharge ion source, the system comprising a screen grid and an accelerator grid each constituted by a respective frame and a set of wires held parallel by supports and fixed to said frames by means of springs, the frames and the grids being assembled together by means of insulators to which they are fixed. According to the invention, the system further comprises a decelerator grid constituted by a frame and a set of wires, the frame of the decelerator grid being engaged in the frame of the accelerator grid and being separated therefrom by insulators. The supports of the wires are constituted either by a comb-shaped plate or by rollers with at least one of the rollers installed in the screen grid being shaped so as to be barrel-shaped, having a larger diameter in its center than at its ends. The pitch of the wires of the screen grid is preferably determined in such a manner as to ensure that the outermost beams converge towards the central beam by a predetermined amount.