Portal verification radiographic element and method of imaging
US5952147A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 29, 1998 |
| Grant date | Sep 14, 1999 |
| Priority date | — |
| Expiry date | Apr 29, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S430/167
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Portal radiographic elements and a process of confirming the targeting of a beam of X-radiation of from 4 to 25 MVp using the portal radiographic elements are disclosed. The X-radiation is directed at a shield containing a port to create a beam. The beam is directed at a selected anatomical feature of a patient over a period of at least 30 seconds. The portion of the beam that passes through the patient impinges on a metal screen, causing it to emit electrons, and the electrons impinge upon a fluorescent screen, causing it to emit light that exposes a portal verification radiographic element to create a latent image in light-sensitized silver halide grains. A processor is employed to convert the latent image to a viewable silver image from which intended targeting of the X-radiation beam can be verified. The processor relies on attenuation of an infrared beam of a wavelength from 850 to 1100 nm by the radiographic element for activation, and at least one of the hydrophilic colloid layers of the radiographic element contains desensitized silver halide grains to increase the specular density of the radiographic element in the wavelength range of infrared sensors that control the proc…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.