It is an object of the present invention to provide a transmission imager which can produce a transmission image from two or more different view points with the use of a simpler arrangement.The transmission imager according to the present invention is provided having a radiation source 2 for radiating radioactive rays from its target 2a, a radiation detector, and a specimen table provided between the target 2 and the radiation detector for having a specimen to be examined placed thereon, wherein the radiation detector is arranged with its detecting surface at the center P extending substantially at a right angle to a reference axis L1 or L2 which extends from the center P to the target 2a. In particular, the transmission imager is characterized in that the radiation detector is a combination of two, first and second, radiation detectors 3 and 4. The first radiation detector 3 is arranged to be moved to and from the target 2a by the action of a driving mechanism and thus positioned further from the target 2a than the second radiation detector 4. The radiation source 2 is specifically arranged in relation to the two, first and second, radiation detectors 3 and 4 so that its target 2a comes at an angle to face a cathode 2b which is disposed closer to the second radiation detector 4.