Film cassette having marker for identifying the exposure side of a medical radiograph
US5189689A · kind A · utility
Inventor
Key dates
| Filing date | Nov 4, 1991 |
| Grant date | Feb 23, 1993 |
| Priority date | — |
| Expiry date | Nov 4, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B42/047
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention provides an X ray film cassette with a permanent marking means for identifying the side of the radiographic film that faced the X ray tube during exposure. Such identification is achieved irrespective of whether the film is exposed through the cover or base of the cassette and does not require any separate action by the X ray technologist, eliminating the element of human error. In a preferred embodiment, the working means is comprised of chirally asymmetric X ray opaque and/or light-opaque letters or markings permanently mounted in the film cassette. A user friendly apparatus is described, for installing the light-opaque markers on the intensifying screens of the X ray film cassette.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.