What is the first step in solid-state image formation?

• A. X-rays hit the scintillator
• B. Light hits the sensor
• C. Electrons accumulate
• D. Heat is generated

Answer: (A)

The first step in solid-state image formation is the interaction of incoming X-ray photons with a scintillator material, which absorbs the X-rays and converts them into visible light. That light is then detected by the sensor, where it produces an electrical signal as photons are converted into charge. Heat generation is not involved in forming the image signal. In this chain, the initial X-ray–to–light conversion is what enables the sensor to produce a usable image, making X-rays hitting the scintillator the correct first step.