Linear tomographic technique allows enhanced visualization of objects in a single body section (focal plane) while blurring the other sections above and below. This is achieved by a coupled linear motion of the x-ray tube and film-bucky during exposure such that the central ray of the x-ray beam always passes through the pivot point (fulcrum) and the film centre. Under this type of exposure and geometry, the focal plane is parallel to the film-plane and the objects oriented perpendicular to the focal plane provide the maximum shadow relative to other orientations. A new microprocessor controlled linear tomographic device can offer conventional, tilted, stereographic, and panoramic exposure sweeps to optimize the focal plane object contrasts depending on the object orientation. The angular interval of x-ray exposures is selectable from the control panel. A functional description of the Linear Orientation Tomographic System is presented.
"Linear Orientation Tomographic System", Proc. SPIE 0347, Application of Optical Instrumentation in Medicine X, (29 December 1982); doi: 10.1117/12.933830; https://doi.org/10.1117/12.933830