It was developed in the context of computer graphics to render 3D scenes, but it has been also used in other similar areas such as acoustics and electromagnetism simulations.
This sort of implementation is rarely used, as the geometric processes involved are much more complex and therefore expensive than simply casting more rays through the pixel.
In recent years, Monte Carlo algorithms like distributed ray tracing and Metropolis light transport have become more popular for rendering calculations.
Similar to photon mapping, backwards beam tracing may be used to efficiently model lighting effects such as caustics.
[7] In both of these applications, beams are used as an efficient way to track deep reflections from a source to a receiver (or vice versa).