Patent · US Expired

System for measuring radiation doses in radiotherapy apparatus

US4034222A · kind A · utility

9Cited by
5References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 12, 1976
Grant dateJul 5, 1977
Priority date
Expiry dateApr 12, 1996

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61N5/1048
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

A system for measuring radiation doses in radiotherapy comprises two identical metering networks energized in parallel from a common radiation source, each network including an integrating amplifier whose time constant is variable by the short-circuiting of an input resistor. A manually or automatically reversible switch selectively foreshortens the time constant of one or the other amplifier whereby the corresponding metering network controls the cutoff of the radiation source whenever the emitted radiant energy reaches a predetermined value. The other network, acting as a backup, takes over the radiation cutoff upon failure of the controlling network; this takeover may be indicated by a set of signal lamps jointly controlled by the reversing switch and by a counting unit of the standby network.

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