Patent · US Expired

Adjustable collimator

US4277685A · kind A · utility

38Cited by
10References
28Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 12, 1978
Grant dateJul 7, 1981
Priority date
Expiry dateJun 12, 1998

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03B42/02
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

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 t…

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