Final answer:
In computed tomography (CT), the beam is collimated at the detection system. The collimation process involves restricting the X-ray beam to a specific size and shape using metal collimators.
Step-by-step explanation:
In computed tomography (CT), the beam is collimated at the detection system.
The collimation process involves restricting the X-ray beam to a specific size and shape. This is done using metal collimators, which are adjustable plates with holes or slits that allow only the desired portion of the X-ray beam to pass through.
By collimating the beam, CT scans can be more precise, reducing scatter radiation and improving image quality.