The duty cycle is the part of the operation cycle of an accelerator during which radiation is produced. The duty cycle is the product of the pulse duration and the pulse-repetition frequency.

See also Duty Cycle in MRI.

A dye is usually a coloring agent. In medical imaging the term dye refers to radiopaque material used during x-ray examinations to provide or increase contrast in the different tissues and organs. Dye usually refers to intravenous contrast agents.

See also Contrast Agents.

The dynamic range describes the range of x-ray intensities a detector can differentiate. A high dynamic range provides the discrimination between small differences in x-ray attenuation.
A current CT scanner has approximately a dynamic range of 1,000,000 to 1 and 1,100 views or projections a second.