Radiographic Technique And Interpretation Essay Research Paper

Production of x-rays requires training a stream of electrons produced at a methal cathode on a metal anode. As the electrons collide with atoms in the anode, they are stopped but their energy is released in two forms–mostly heat and a very small quantity (1%) as x-rays. The area ofthe cathode where the fast moving electrons collide is called the focal spot and is in fact the source of the x-rays. The x-rays generated at the focal spot travel out in all directions. However, the head of the x-ray machine is constructed in such a way as to absorb “stray radiation and at the same time emit a central beam, which emerges from the cone and is the useful beam.The x-rays traveling in the central beam are not continous, but are emitted in pulses of 1/120 of a second due to the fact that are produced by 60 cycle per second AC current. In addition, as Fitgerald points out, the x-rays diverge as they proceed from the target, which is not simply a point but an area with finite dimensions no matter how small. These features of the central beam are essential to the understanding of what we do to produce x-ray images and what we realy see as we interpret the record of the object radiographed.