Fluoroscope Case Study

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There are many factors affect the quality of fluoroscopic image as fluoroscopy system is much more complex compare to common radiography system. The factors included are contrast, resolution, distortion and quantum mottle. Firstly, contrast of the image can be manipulated by adjusting the amplitude of the video signal. Amount of scatter radiation is the main factor to reduce the image intensified fluoroscopic contrast. Main causes of scatter radiation comes from scattered ionizing radiation, penumbral light scatter in the input and output screens and light scatter in the image intensification tube. Scattered ionizing radiation will produces scatter photons arriving at the input phosphor and produces some background fog from incident photons that are transmitted through the tube to the output screen or that backscatter from the output to the input screen. Light photons also scatter as they are reflected and refracted within the tube. Since light is emitted isotropically from the output phosphor, some of it will strike the input screen, causing a backscatter effect. All these effects combine to produce a background fog that raises the base density of …show more content…

For nonvideo recording, such as spot filming or direct optical viewing, the ability to resolve recorded detail in a fluoroscopic system will vary depending on the geometrical factors, just as in static radiography. However, the geometrical factors are different, including minification gain, electrostatic focal point, input and output screen diameter, and viewing system resolution (especially television system resolution),as well as OID and phosphor size and thickness. CsI image intensifiers are capable of 2lp/mm. Optical mirror systems that permit indirect viewing of the fluoro screen are capable of 3 lp/mm. Magnification or multifield image intensifiers are capable of up to 2.7lp/mm in the magnification

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