According to the inverse square law, how does decreasing the source-to-image distance (SID) affect receptor exposure?

The inverse square law states that the intensity of radiation is inversely proportional to the square of the distance from the source of radiation. This means that as you decrease the source-to-image distance (SID), the intensity of radiation that reaches the image receptor increases significantly.

When the distance is halved, for example, the intensity of radiation becomes four times stronger because it is 1/(0.5^2) or 4. This increase in intensity results in greater receptor exposure, meaning that the image receptor will receive more radiation and thus will exhibit a higher level of exposure.

Understanding this principle is essential for radiography because it enables professionals to manipulate exposure factors effectively, ensuring optimal image quality while minimizing the risk of overexposure to both the patient and the receptor. Adjusting the SID allows radiographers to control the exposure received and achieve the desired diagnostic outcome.