The imaging principle and maintenance of DR flat panel detector

The DR system of the DR flat panel detector is mainly composed of a power supply system, a control system, a high-voltage generating device, an X-ray tube device, a mechanical device, an imaging device (flat panel detector) and an image post-processing system. Compared with the traditional X-ray TV system, the biggest difference lies in the imaging equipment part: the DR flat panel detector replaces the image intensifier tube and realizes digital direct imaging.
The system of the DR flat panel detector is composed of a ray receiver, a command processor and a power module. X-rays are first converted into visible light by dielectric materials (scintillation crystals), then converted into electrical signals by photosensitive elements (planar amorphous silicon TFT sensor arrays), and finally converted into digital signals by readout circuits (A/D).
Maintenance process of DR flat panel detector
(1) Understand the internal structure of the DR flat panel detector. (2) Measure the voltage of the plate node. (3) Check whether the system control IC has not sent a signal to the Ic16 (74LVC540) tri-state bus buffer, and Ic16 has no high-level signal to the base of Q4. In order to determine whether the system control IC is damaged, please try to disconnect the digital power supply from a group of power supplies of the system control IC. The tablet will immediately report a communication error, indicating that the possibility of system IC failure is very small. The next step should be to determine whether the external working conditions are met. (4) When the power is detected to be unstable, pin 8 outputs a reset signal. Please check whether the peripheral components and power supply of MB3771 are normal in order to judge that the Ic25 itself is faulty. Troubleshooting after replacement.

Author：Lillian