Abstract
A system has been previously described by the writer* whereby an object may be radiographed with a narrow beam of rays as produced by means of a slit-shaped diaphragm, the resulting radiogram being greater in area than the cross-section of the beam. This is accomplished by moving the tube, during exposure, in a plane parallel to the film and in a direction parallel to one side of it (Fig. 1). It will be seen that as regards one dimension all rays reaching the film are vertical to it. A dry pelvis radiographed in this manner is shown in Fig. 2, the elliptical shadow superimposed being that of a circular metal cone on which the pelvis rested. All those dimensions parallel to the direction to the tube-traverse are recorded exactly to size. With this system, tube distance is not a factor even if varied during exposure. Exposures are calculated by dividing width of slit-image into length of tube traverse. In many cases where the diaphragm is midway between tube and film, the width of the slit-image will be twi...
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
