A tomographic scanning apparatus for scanning an object under test and retrieving projection-related data of the object with a light/radiation source and a detector operating in conjunction therewith includes an object carrier, a light/radiation source carrier, a detector carrier, a control module, a processing module, and a rail system (or rotating arm). The object carrier is disposed at a center of the rail system or a center of rotating tracks of the rotating arm. The light/radiation source carrier and the detector carrier move along a rail of the rail system or along the rotating tracks of the rotating arm. The carriers have a rotating mechanism, moving mechanism, and/or height adjusting mechanism for performing rotation, horizontal movement, and/or height adjustment. Accordingly, the tomographic scanning apparatus operates in various ways to suit various applications, respectively.
