PRODUCING IMAGES BY IONOGRAPHY

摘要

A method and apparatus for producing images from an electrically insulated film (6) on which a latent ionographic image has been formed by supporting the film between a pair of electrodes in a gas ionisation chamber exposed to x-rays. The film (6) is advanced on a support surface beneath at least one scanning electrode (13) signals derived from the said at least one scanning electrode (13) are digitised, and an image representative of the digitised signals is displayed. The film (6) may be supported in a cassette and advanced beneath said at least one scanning electrode (13) on the surface of a rotating drum (11). A predetermined voltage is applied between the support surface and said at least one scanning electrode (13) such that the potential difference between the film (6) and said at least one scanning electrode (13) is less than the potential difference between regions of maximum and minimum potential on the surface of the film (6).