Patent Number: 039379710
Section: abstract

A focused shield for use in connection with a radiation therapy machine or the like is constructed using a method and apparatus that results in a shield having a bevel-walled aperture. The aperture is cut into a focused shield blank and has a predetermined configuration corresponding to a selected area of a patient to be exposed to a field of radiation with the angularity of the aperture sidewalls relative to the radiation rays being such that any rays of a radiation beam in alignment with the aperture enter the same and do not strike the sidewalls thereof but rather pass through the aperture in an unimpeded manner. The method and apparatus employed in making the focused shield incorporates the use of a focused shield blank having a convexly rounded bottom side and a blank holding fixture, adapted for use with a band saw or the like, having a bowl-shaped concavity for receiving the blank and positioning the same on a surface that has a radius of curvatuve corresponding to the curvature of the blank bottom wall during the cutting of the aperture into the blank.