Focal spot blooming is the unwanted change in the focal spot size of an X-ray tube during change in exposure.[1]

Cause

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Focal spot blooming is caused due to increased mAs. When high exposure setting are used, the electron beam from the cathode fail to focus on a particular point because of electrostatic repulsion.[2]

References

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  1. ^ Fosbinder, Robert; Orth, Denise (2011-02-16). Essentials of Radiologic Science. Lippincott Williams & Wilkins. ISBN 978-0-7817-7554-0.
  2. ^ Pettersson, Holger; Allison, David J. (1998). The Encyclopaedia of Medical Imaging. Taylor & Francis. p. 159. ISBN 978-82-91942-00-1.