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Off-Focus Radiation - Video Lesson

Hey, everybody. Welcome back. This short video is about off focus radiation. All focus radiation occurs when x rays are created from interactions with materials within the x-ray tube other than the focal spot. During x-ray exposure, electrons from the cathode collide with the focal spot on the anode. And through that process, x rays are produced. Notice that these x rays are fairly well aligned with each other. We also have a collimator to help control the size of the beam. Most x rays leaving the tube are produced in this way, but not all. Some electrons actually bounce off of the anode and collide with other parts of the x-ray tube away from the focal spot, such as the glass envelope, the cathode assembly, and even other parts of the anode. Some x rays are created with interactions with these materials