Computed Radiography (CR)
Like conventional Radiography Testing (RT) using film, radiation is used to expose the CR cassette (phosphorus screen), which is then moved from the inspection site and taken to the reader location.
Unlike film RT, no hazardous chemicals are required and the development time is reduced from almost an hour to less than 30 seconds.
The digital image on the CR plate is evaluated on the analysis station (PC) using software. There are numerous tools available within the software that allow the reviewer to enhance the digital image, such as adjusting the contrast and brightness to aid in the evaluation of the image, changing from a negative to a positive image, magnification, annotation and built in measurement tools to name a few. The image plate is then erased and is ready for re-exposure.
Although the analyst can manipulate the image, the original file integrity cannot be compromised, altered or saved which maintains the integrity of the original image. In fact, any changes made by the analyst during the review for acceptance, can accompany the data file so a third party reviewer can see the image settings used for acceptance.
Another added benefit of CR is that there is no film to archive and store that WILL degrade over time. Film is replaced by a digital image that may be stored on a portable hard drive or server, and when stored on a server can be viewed by various locations worldwide. The CR software also allows third party review without having to be present.
For additional information on CR visit VMI at www.starrview.com