title: Optical radiation-field indication in X-ray tubes with more than one focus.
authors.affiliation: Department of Diagnostic Radiology, Karolinska Hospital, Stockholm, Sweden.
authors.forename: O
authors.initials: O
authors.lastname: Mattsson
mesh_terms: D004867:Equipment Design; D006801:Humans; D008027:Light; D055095:Optics and Photonics / Q000295:instrumentation*; D011878:Radiotherapy / Q000295:instrumentation* / Q000592:standards