Which of the following is essential to transfer a latent image from the imaging plate to a digital radiograph?

• A. Imaging plate reader/digitizer
• B. Scintillator
• C. PSP
• D. Developer

Answer: (B)

The essential part is reading out the stored signal from the storage phosphor plate. In computed radiography, the latent image is held in the storage phosphor layer (PSP) as trapped energy after X-ray exposure. To convert that stored information into a digital radiograph, the plate must be read by an imaging plate reader/digitizer. Inside the reader, a laser scans the plate and stimulates the trapped electrons to emit photostimulated luminescence light. This light is detected and digitized to form the image. The PSP is the storage medium, not the device that transfers the image to digital form. A scintillator is used in other detector designs to convert X-rays to light before detection, but CR relies on the PSP and the reader for the transfer. The developer is not involved in this process.