Patent · US Expired

Radiation therapy unit

US4987309A · kind A · utility

121Cited by
10References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 22, 1989
Grant dateJan 22, 1991
Priority date
Expiry dateNov 22, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG21K1/046
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

A radiation therapy unit with a beam of rays propagating from a focal point along a beam axis comprises a radiator head arranged on the beam axis with a double-focus multi-leaf collimator. The multi-leaf collimator exhibits a plurality of adjacently arranged diaphragm plates which in each case have two side faces, two front faces and an inside and an outside face. Each side face of each diaphragm plate forms a part of a surface area of a cone, all such cones having both a common cone axis which extends perpendicularly to the beam axis through the focal point, and a common cone point which coincides with the focal point. Means are provided for guiding the diaphragm plates so that each diaphragm plate performs a pure rotation about the cone axis during its displacement.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.