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:
Mar. 06, 2001
Filed:
Mar. 15, 2000
Mark Dinsmore, Sudbury, MA (US);
Photoelectron Corporation, Lexington, MA (US);
Abstract
A modular multistage accelerator for use in an X-ray treatment system includes a first 10 kV acceleration stage which houses an electron beam gun supplied with −50 kV of voltage. The modular multi-stage accelerator includes four additional 10 kV stages placed in series with the first stage to achieve a 50 kV accelerator overall. Each stage is shielded to prevent stray electrons from being propagated along the length of the drift tube. The triple point within each modular stage is recessed to significantly reduce the emission of stray electrons within each stage. Additionally, the beam current at the X-ray emitting probe of the X-ray source is measured by isolating the beam current to a beam current measuring circuit in electrical connection with a nulling junction node, wherein other currents within the circuit are nulled at the nulling junction node and the beam current flows to the beam current measuring circuit.