Ionization chamber having off-passageway measuring electrodes
US5672878A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 24, 1996 |
| Grant date | Sep 30, 1997 |
| Priority date | — |
| Expiry date | Oct 24, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J47/02
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An ionization chamber for monitoring a radiation beam includes a housing having a primary beam passageway and a number of secondary beam cells that are adjacent to the primary beam passageway. The primary beam passageway passes entirely through the housing. In the preferred embodiment, a large-area beam measuring electrode and an array of small-area beam measuring electrodes are each coaxial with the primary beam passageway. Also, in the preferred embodiment, each secondary beam cell includes a beam measuring electrode. Because the portions of the radiation beam that enter the secondary beam cells do not pass through the ionization chamber, these portions do not contaminate the treatment beam, allowing the beam measuring electrodes within the cells to be dimensioned and configured so as to maximize signal strength.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.