What function does lead foil serve in radiographic film?

Lead foil in radiographic film plays a crucial role in preventing film fogging by absorbing scatter radiation. When X-rays are produced, not all of them are directed towards the film; some are scattered in different directions. This scatter radiation can fog the film, causing a reduction in image quality and contrast. By incorporating lead foil, the film can effectively reduce this unwanted scatter radiation, leading to a clearer image.

The presence of lead foil enhances the diagnostic quality of radiographs by ensuring that only the primary beam contributes to the image exposure, thereby minimizing the background noise that scatter radiation creates. This function is essential in maintaining the accuracy and reliability of radiographic diagnostics.