Which components are typically found in a collimator?

A collimator is an essential device used in radiography to narrow the beam of radiation and improve image quality by ensuring that only the desired area is exposed. The correct components found in a collimator include a mirror and a light bulb.

The mirror is used to reflect and direct the light emitted by the light bulb, allowing for visualization and alignment of the radiation beam with the area of interest on the patient or radiographic film. This alignment is crucial for producing high-quality images while minimizing radiation exposure to surrounding tissues.

While rare earth phosphors and other components might be relevant in different aspects of radiographic techniques and imaging systems, they are not typically integral to the functioning of a collimator. This distinction highlights why the other options are not suitable as they include components that do not directly relate to the collimator's purpose and design. Thus, the inclusion of a mirror and light bulb in the correct answer underscores the essential features of a collimator.