In digital radiography, what is referred to as the fill factor?

The fill factor refers to the proportion of the pixel area in a digital radiography detector that actually senses radiation. In imaging systems, especially in digital detectors, each pixel consists of both a sensing area and non-sensing area. The sensing area is responsible for collecting the radiation that forms the image, whereas the non-sensing area may include circuitry and other components necessary for the pixel’s operation.

A higher fill factor indicates that a greater percentage of the pixel's total area is available for capturing radiation, which enhances image quality, sensitivity, and resolution. Consequently, the fill factor influences not only the potential image resolution but also factors such as noise and overall sensitivity of the system to low radiation levels.

Understanding the fill factor is crucial in the design and evaluation of radiographic systems, as it directly impacts the efficiency and quality of the images produced in medical imaging and other applications.