(under subclass 145) Subject matter comprising control of X-ray beam shape, size, axial direction, or focal length.
(1) Note. This subclass includes X-ray opaque aperture plates, source mounted masking devices, etc.
(2) Note. Beam masking devices positioned on or adjacent an irradiated object so as to protect the object are considered radiation shields and are classified in Class 250, Radiant Energy, subclass 515.1.
