Robert Roland Heck

US Patent:

56549962, Aug 5, 1997

Filed:

Mar 29, 1996

Appl. No.:

8/623724

Inventors:

Todd H. Steinberg - Antioch CA
Michael John Smidebush - Concord CA
Robert J. Heck - Pacifica CA

Assignee:

Siemens Medical Systems, Inc. - Iselin NJ

International Classification:

A61N 510

US Classification:

378 65

Abstract:

A method and an apparatus for positioning blocking elements (310, 320) in a collimator (4) is provided. The collimator (4) is located in a radiation emitting device (2) delivering a radiation beam (1) to an object (13). The collimator (4) includes a plurality of movable blocking elements (310, 320). The blocking elements (310, 320) are movable for defining an opening (330) for the radiation beam (1). After forming an opening (330) with the blocking elements (310, 320), a calibration tool (400) having a cross bar (410) is inserted in the opening (330) and the cross bar (410) is moved to a defined first position (500) in the opening (408) of the calibration tool. A group of blocking elements is then moved to the cross bar (410). The cross bar (410) is then moved to a defined second position (510) in the opening (408) and the a group of blocking elements is moved to the cross bar (410). The beformentioned steps are repeated until the collimator is calibrated or all the blocking elements (310, 320) are positioned.