Plural image signal system for scanning x-ray apparatus
US4259582A · kind A · utility
Inventor
Key dates
| Filing date | Nov 2, 1979 |
| Grant date | Mar 31, 1981 |
| Priority date | — |
| Expiry date | Nov 2, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/32
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Radiographic images are produced by situating a subject (13) between a scanning x-ray source (16) and an x-ray detector (14) to produce electrical signals indicative of variations of x-ray transmissivity in different regions of the subject (13). A signal processing system (11) enables simultaneous display of a plurality of visible images at a plurality of display devices (52 to 55) with each image emphasizing a different aspect of the information generated by a given scanning of the subject. A feedback circuit (68) from the detector (14) to the x-ray source (16) maintains the average level of the detector signal constant while allowing short term fluctuations so that only abrupt or brief changes of x-ray transmissivity in the subject are visible in a first image at a first display device (52). A second image signal circuit (93) recovers the data suppressed by the feedback circuit (68) to enable a full contrast range image to be presented at another display device (53) and to enable display at additional display devices (54, 55) of still more images, each of which emphasizes a different selected contrast range from the total range of subject transmissivity variations developed by th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.