Film-based dual energy radiography
US4561054A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 13, 1983 |
| Grant date | Dec 24, 1985 |
| Priority date | — |
| Expiry date | Oct 13, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/04791
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Apparatus for reading out individual X-ray images recorded on a double-emulsion radiographic film or on separate films that were coincident when exposed simultaneously to a polyenergetic or broad X-ray photon energy spectrum beam emergent from a body and where an image corresponding to one obtained with a low energy part of the spectrum is formed on one film and an image corresponding to a higher energy part of the spectrum is formed on the other. One readout apparatus is for the case of two separate films which, after development, are illuminated from the back and optically scanned to derive analog signals representative of the intensities of spatially corresponding picture elements on each film. Another apparatus is for the case where the two images are on opposite sides of a film and are represented by alternate fine image information lines obtained by interposing a grid during the X-ray exposure. Another is for the case where a reflective layer is disposed between the film images during readout. In all cases the films are optically scanned and the resulting analog signals are digitized and variously processed to yield an image representative of that which is different between t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.