Question

Thin film transistors (TFTs) are used in direct digital radiography systems to:

a)              Produce a flash of light

b)             Convert the X-ray energy to an electrical charge

c)              Temporarily store the electric charge

d)             Trap the electrons in the photostimulable phosphor

e)              Bind the photostimulable phosphor to the glass screen

Answer 1

answer is (b) Convert the X-ray energy to an electrical charge.

Direct-conversion detectors have an X-ray photoconductor, such as amorphous selenium, that directly converts X-

ray photons into an electric charge.

The selenium-based technology uses an amorphous selenium-coated thin-film-transistor (TFT) array to capture and

convert X-ray energy directly into digital signals. It is a direct-conversion technology that converts X-ray beams into

electric charges directly.