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:
Apr. 30, 1991
Filed:
Oct. 07, 1988
Francis J Span, Eindhoven, NL;
Brian S Driver, Langley Green, GB;
U.S. Philips Corporation, New York, NY (US);
Abstract
A collimator is described for a shielded effective point source of penetrating radiation, e.g. a radiotherapy machine which includes, after a primary collimator 16, a succession of a multileaf collimator 17, and a first and a second pair of independently adjustable block diaphragm leaves 30, 31, and 35, 36 at right angles to each other. By using rectilinear displacement of the multileaf collimator leaves 18 and the block diaphragm leaves 30, 31, a compact arrangement can be provided which fits into a standard RT collimator head. By curving the inner edges of the leaves to be tangential to the boundary ray an optimally reduced penumbra can be achieved. The block diaphragms enable the radiation leakage found in prior multileaf collimators to be minimized for small and off center irradiation patterns.