Film digitization using a cooled, fiber-optic faceplate-bonded charge-coupled device

Photographic film remains critical to x-ray diagnostics because it is the most resilient option for photon detection in high-radiation environments such as those present in inertial confinement fusion experiments. Film is traditionally digitized using a microdensitometer, which measures the optical density of a 20-μm square region and builds the image dataset by raster scanning. While the microdensitometer offers a high dynamic range, it requires a long processing time and is limited to a 12-bit digitizer resolution. A 16-bit, cooled CCD (charge-coupled device) bonded to a 6-μm-core fiber optic faceplate was tested as an alternative method for digitizing film. The film’s emulsion layer was placed in direct contact with the fiber-optic faceplate to reduce scattered light. Multiple images were captured and averaged to mitigate photon statistical noise and digitizer noise intrinsic to the CCD. Spatial resolution and dynamic range were measured and compared against a Perkin-Elmer PDS microdensitometer system. Further development must be done for this platform, but a preliminary look suggests that a fiber-bonded CCD serves as a viable method for fast, quantitative film digitization.