Infographics / Digital Radiography

Radiographic Film Construction & Emulsion

Left: a cross-section of double-emulsion (duplitized) film showing, from outside in, a protective supercoat, a silver-halide-in-gelatin emulsion, an adhesive layer and the polyester base, then a mirror-image adhesive, emulsion and supercoat on the other side. Right: a magnified silver halide grain where an x-ray or light photon frees an electron from a halide ion; the electron is trapped at a sensitivity speck, where a silver ion is reduced to a neutral silver atom to form the latent image.