What is a primary feature of third-generation CT scanners?

The primary feature of third-generation CT scanners is the fan-shaped beam. This design represents a significant advancement over earlier generations, where the x-ray beam was either pencil-shaped or a rotating collimator was used. The fan-shaped beam allows for the acquisition of a wider slice of the body in a single rotation, improving image quality and reducing scan times.

By utilizing the fan-shaped beam, these scanners can capture more data in a shorter timeframe, which enhances the speed of the imaging process and minimizes motion artifacts from the patient. The geometry of the fan beam also contributes to improved image resolution and the ability to produce thinner slices for more detailed images.

In comparison, planar imaging pertains to techniques that involve flat images rather than cross-sectional imaging and is not a characteristic of third-generation CT technology. The mention of no rotating components describes a different type of scanner entirely, which is more relevant to advanced or alternative imaging systems like certain types of flat-panel detectors. Single detector arrays refer to earlier or different generations of CT technology that used only one detector rather than the multiple detectors found in third-generation systems, which allow for more efficient data collection.