Question 619
{"accessible":false,"alternatives":[{"id":3103,"text":"greater anode heel effect"},{"id":3104,"text":"larger effective focal spot"},{"id":3106,"text":"reduction in geometric blurring"},{"id":3105,"text":"smaller actual focal spot"},{"id":3107,"text":"smaller field size"}],"archived":false,"correctAlternativeId":3104,"explanation":"\u003cp\u003eAccording to the \u003ca href=\"/articles/line-focus-principle\"\u003eline focus principle\u003c/a\u003e\u0026nbsp;the effective focal spot (\u003cem\u003ef\u003c/em\u003e) size can be determined by\u0026nbsp;the\u0026nbsp;real focal spot size (F) * sin of the anode angle:\u003c/p\u003e\u003cp\u003e\u0026nbsp;\u003cem\u003ef\u003c/em\u003e\u0026nbsp;= F*sinθ\u003c/p\u003e\u003cp\u003eTherefore increasing the angle will result in a larger effective focal spot.\u003c/p\u003e\u003cp\u003eAdapted from\u0026nbsp;\u003ca href=\"https://en.wikibooks.org/wiki/Basic_Physics_of_Digital_Radiography\"\u003eBasic Physics of Digital Radiography\u003c/a\u003e\u0026nbsp;by\u0026nbsp;Kieran Maher,\u0026nbsp;with author's permission (License:\u0026nbsp;\u003ca href=\"https://creativecommons.org/licenses/by-sa/3.0/\"\u003eCreative Commons\u0026nbsp;BY-SA 3.0\u003c/a\u003e).\u003c/p\u003e\u003cp\u003eThe magnitude of the anode heel effect increases as anode angle decreases.\u003c/p\u003e\u003cp\u003ePrimary X-ray beam field size increases with increasing anode angle.\u003c/p\u003e\u003cp\u003eThe increase in effective focal spot size results in an increase in geometric blurring/unsharpness.\u003c/p\u003e","id":619,"imageUrl":null,"imageAttribution":null,"imageAttributionCaseInfo":null,"firstQuestionPath":"/questions/2605","nextQuestionPath":null,"relatedArticles":[{"id":8178,"title":"Anode (x-ray tube)","link":"/articles/anode-x-ray-tube?lang=us"},{"id":29775,"title":"Anode heel effect","link":"/articles/anode-heel-effect?lang=us"},{"id":29771,"title":"Focal spot","link":"/articles/focal-spot?lang=us"}],"alsoUsedIn":[],"stem":"\u003cp\u003eIncreasing the anode angle of a diagnostic x-ray tube results in a...\u003c/p\u003e","menuLinks":[{"text":"Report problem with question","url":"https://docs.google.com/forms/d/e/1FAIpQLSfO3soWYhOjJ7yErSysyCe5V4A1CqW7WK3rDA7MtAkecMGqNw/viewform?entry.1624461248\u0026entry.553583435=https://radiopaedia.org/questions/619"}],"attemptsPercentages":[{"alternativeId":"3107","percentage":2},{"alternativeId":"3105","percentage":10},{"alternativeId":"3103","percentage":15},{"alternativeId":"3108","percentage":3},{"alternativeId":"3106","percentage":16},{"alternativeId":"3104","percentage":55}],"promptToLogin":false,"questionManager":false,"articleId":"line-focus-principle"}