Adjustable collimator

Patent · Tue Jul 07 04:00:00 EDT 1981

OSTI ID:5857527

Carlson, R W; Covic, J; Leininger, G

In a rotating fan beam tomographic scanner there is included an adjustable collimator and shutter assembly. The assembly includes a fan angle collimation cylinder having a plurality of different length slots through which the beam may pass for adjusting the fan angle of the beam. It also includes a beam thickness cylinder having a plurality of slots of different widths for adjusting the thickness of the beam. Further, some of the slots have filter materials mounted therein so that the operator may select from a plurality of filters. Also disclosed is a servo motor system which allows the operator to select the desired fan angle, beam thickness and filter from a remote location. An additional feature is a failsafe shutter assembly which includes a spring biased shutter cylinder mounted in the collimation cylinders. The servo motor control circuit checks several system conditions before the shutter is rendered openable. Further, the circuit cuts off the radiation if the shutter fails to open or close properly. A still further feature is a reference radiation intensity monitor which includes a tuning-fork shaped light conducting element having a scintillation crystal mounted on each tine. The monitor is placed adjacent the collimator between it and the source with the pair of crystals to either side of the fan beam.

• Assignee: Ohio Nuclear Inc
• Patent Number(s): US 4277685
• OSTI ID: 5857527
• Country of Publication: United States
• Language: English

Related Subjects

550602* -- Medicine-- External Radiation in Diagnostics-- (1980-)
62 RADIOLOGY AND NUCLEAR MEDICINE
BEAM MONITORS
CAT SCANNING
COLLIMATORS
COMPUTERIZED TOMOGRAPHY
CONTROL EQUIPMENT
DESIGN
DIAGNOSTIC TECHNIQUES
ELECTROMAGNETIC RADIATION
EQUIPMENT
GAMMA RADIATION
IMAGE PROCESSING
IONIZING RADIATIONS
MEASURING INSTRUMENTS
MONITORS
PROCESSING
RADIATION MONITORS
RADIATIONS
TOMOGRAPHY
X RADIATION