Breast cancer screening programes are helping to reduce the mortality rates of women by finding cancer in its early stages when it is easier to treat. Sweden was one of the first countries in the world to introduce a screening program after successful clinical trials in the 1980s.

The first mammography systems in use in screening programs were analog film-screen (FS) units where the x-rays are captured in a photographic film with the aid of an intensifying screen. The image is then developed in a lab and displayed on light boxes. The images then have to be handled manually and stored in large archives. The intrinsic properties of the film-screen itself sets limits on dose levels and exposure factors, as the film needs a certain exposure to give a good image and both under- and overexposure leads to bad image quality.