Computerised tomographic diagnostic machine - has lens system with bi-convex cylindrical lens between picture amplifier and CRT input

摘要

The computerised tomographic system has a source (2) from which an X-ray beam is directed through part of a patient's body (4) and with an amplifier (6) onto the face (5) of which the colleinated beam is directed. At the output (7) is a strip shaped visible image (8) of reduced size. This is projected by means of a biconvex cylindrical astigmatic lens (9) onto the input (10) of a picture tube (11). The axis (12) of the lens is at right angles to the plane of strip image (8). It is used to focus this image along its own plane and defocus it in the line directions of the image at right angles to this plane. The output (15) of the tube gives a signal corresponding to the absorption of the part of the body being examined.