In physics, backscatter (or backscattering) is the reflection of waves, particles, or signals back to the direction from which they came. It is a diffuse reflection due to scattering, as opposed to specular reflection like a mirror. Backscattering has important applications in astronomy, photography and medical ultrasonography.
Read more about Backscatter: Backscatter of Waves in Physical Space, Backscatter in Waveguides, Backscatter in Photography