Scanner for the recording of radioactivity distribution

In a scintiscanner comprising an upper measuring head and a lower measuring head and associated write heads, the activity distribution measured by the lower measuring head is recorded in the form of a mirror-image if the write heads in the two recording directions are moved in the same direction with respect to each other. However, if the write heads in the one recording direction are displaced opposite to each other, a correct recording is obtained, but it is then very difficult to compare the scintigrams recorded by the measuring heads. The invention describes a simple mechanical device by means of which the write heads can be moved in the same or in the opposite direction with respect to each other. (auth)