scanning

Scanning is the systematic examination of an object, area, or data source to collect information. It typically involves a sensor or measurement device moving across a defined plane or volume, or the object being moved past a stationary sensor. The result is data such as images, spectra, or geometric measurements that can be analyzed or rendered for interpretation.

In medical and biological contexts, scanning refers to imaging procedures that reveal internal structures. Computed tomography (CT) and magnetic resonance imaging (MRI) produce cross‑sectional images used for diagnosis. In digital imaging and documentation, scanners convert physical documents or photographs into electronic files. In logistics and retail, barcode and QR code scanners read encoded information to identify products or track movements.

3D scanning captures the shape and sometimes color of real‑world objects. Techniques include laser scanning, structured‑light or stereo photogrammetry, and time‑of‑flight methods. The output often takes the form of point clouds or polygon meshes used in design, manufacturing, cultural heritage, or virtual reality.

Scanning methods may be raster, systematic, or continuous, and depend on the sensor technology. Common considerations include resolution, accuracy, speed, and the handling of occlusions or reflective surfaces. Data from scanners usually require processing steps such as noise filtering, alignment with reference frames (registration), and reconstruction or visualization.

Applications span healthcare, industrial inspection, archaeology, security screening, environmental monitoring, and research. Safety, privacy, and ethical issues can arise in contexts such as radiation exposure in medical imaging or surveillance scanning. Limitations include cost, accessibility, data size, and potential artifacts or biases in interpretation.