Final answer:
Remnant radiation is responsible for producing the diagnostic portion of the image on the image receptor in medical imaging. It is the altered primary radiation that has passed through and been attenuated by the patient's body, providing the contrasts necessary for a detailed image. Scatter radiation and penumbra may affect image quality but do not contribute to the diagnostic content.
Step-by-step explanation:
In medical imaging, the production of a diagnostic image on the image receptor is made possible by remnant radiation. Remnant radiation refers to the radiation that exits the patient after the x-ray beam has passed through the body. This type of radiation has the necessary information to produce the image, as it has been attenuated by different tissues to various degrees based on their composition and density. Remnant radiation is what creates the contrast and detail in the final image. The energy and type of radiation, as well as the number of photons that strike a given area, all affect the quality of the diagnostic image. It's important to know that scatter radiation can degrade the quality of the image, as it introduces unwanted exposure that does not represent the patient's anatomy accurately. On the other hand, primary radiation is the initial beam emitted toward the patient, but only the remnant of this primary beam contributes to the image after interacting with the patient's tissues. Finally, the penumbra is not radiation but refers to the blurry edge around a shadow in an image, which can also affect image quality.