The working principle of the flat panel detector in the sickle arm X-ray machine

Lillian 5月 26, 2021

Do you know how flat panel detectors work in sickle arm X-ray machines? Today I will give you a general introduction to the working principle of flat-panel detectors in sickle arm X-ray machines. X-ray flat-panel detector imaging principles: flat-panel detectors, is light converted into electrical information? The answer is two kinds of conversion techniques: indirect Indirect conversion flat panel detector consists of cesium iodide and other scintillation crystal coatings and thin film transistors (Thin Film Transistor, T FT) or charge coupled devices (C hargeC oupling Device, C CD) or complementary metal oxides Semiconductor (Com plem en tary M etal Oxide S em i -Conductor, CM OS) structure. The working process of the indirect conversion flat panel detector is generally divided into two steps. First, the scintillation crystal coating converts the energy of X-rays into visible light; secondly, TF T or C CD or C MO S converts visible light into electrical signals. Since visible light will scatter in this process, it will have a certain impact on the spatial resolution. Although the scintillator is processed into a columnar shape in the new process to improve the utilization of X-rays and reduce the scattering, the influence of scattered light on the spatial resolution cannot be completely eliminated [2]. Direct conversion flat panel detector The direct conversion flat panel detector is mainly composed of an amorphous selenium layer (Am orph ou s S elenium, a -S e) T FT. The incident X-rays make the selenium layer generate electron-hole pairs. Under the action of an externally biased electric field, the electrons and holes move in opposite directions to form a current, and the current forms a stored charge in the thin film transistor. The amount of stored charge of each transistor corresponds to the dose of incident X-rays. Through the readout circuit, the amount of charge at each point can be known, and then the X-ray dose at each point can be known. Since amorphous selenium does not produce visible light and has no influence of scattered rays, it can obtain a relatively high spatial resolution.
Seeing here, everyone knows the working principle of the flat panel detector in the sickle arm X-ray machine. Please contact us if you need it.