X-Rays: Even Shorter Wavelengths

Using shorter wavelength photons with greater energies than in the UV presents a different problem. X-rays are capable of penetrating more material without being reflected or absorbed. Medical uses of X-ray energies take advantage of this penetration. Hence, medical X-ray images show shadow pictures of dense structures such as bones that absorb the energy, but the X-rays go right through soft tissue without much absorption. Visible light gets reflected from the body's surface giving a much different picture. The medical X-rays or soft X-rays have the lower energies in the X-ray continuum. They penetrate to give shadow pictures or they can be focused with difficulty onto dense detectors to give transmitted images.