Final answer:
The percentage of energy from absorbed x-ray photons converted into light can vary, with approximately 33% of the photon energy typically lost to heat due to electron interactions within the material. The Compton effect plays a role in this energy conversion, especially as x-ray energy increases.
Step-by-step explanation:
The percentage of energy from absorbed x-ray photons that is converted into light rather than into infrared or heat, which is regarded as wasted, varies depending on the energy of the x-ray photons and the material with which the x-ray interacts. As the energy of x-rays increases, the Compton effect becomes more significant in the attenuation of the x-rays. This attenuation involves the x-ray scattering from an atom's outer electron shell, transferring some kinetic energy to the ejected electron and consequently losing energy itself, which can contribute to heat production.
Absorbed low-energy x-rays offer better contrast for imaging purposes because they are less scattered and more absorbed by denser materials. To enhance the contrast, substances with a high atomic number (high Z) like barium or iodine may be introduced to the body. Despite this, a significant fraction of the incident photon energy is lost as heat when the energized electrons interact with the crystal lattice.
It is highlighted that approximately 33% of the incident photon energy is typically lost to heat. Such inefficiencies are an important consideration in both medical imaging technology and research settings where the management of x-ray exposure and energy transfer is critical.