California Fluoroscopy State Board Practice Exam

In a fluoroscopy system that employs a direct-capture flat panel image receptor plate (FPIR), the latent analog image is stored within the thin film transistor (TFT) and capacitor array. The TFT array is essential in this process because it converts the analog signals generated by the incoming x-rays into electrical signals.

When x-rays strike the amorphous selenium layer of the FPIR, an electrical charge is generated. This charge is then captured in the capacitors associated with each pixel in the TFT array. The result is that each pixel holds a latent image in the form of stored electrical charge. The information held in this array is ultimately read out by the system to create a visible digital image that can be displayed and analyzed.

The TFT's integration with the capacitor array is vital for quick readout times and high-resolution imaging, making it a key component in direct-capture systems for fluoroscopy. This highlights the importance of understanding how latent images are formed and stored in imaging technology, directly impacting imaging quality and diagnostic capabilities.