What is reflection in the context of laser physics?

In the context of laser physics, reflection refers to the phenomenon where a laser beam encounters a surface and bounces back instead of penetrating further into the material. When light hits a reflective surface, the angle at which it hits (the angle of incidence) is equal to the angle at which it leaves (the angle of reflection). This principle is crucial in various applications of lasers, including diagnostics and surgery, where precise control and direction of the beam are necessary.

Understanding reflection is important in distinguishing it from other interactions like absorption, where energy is taken up by the material, or scattering, where photons are deflected in many directions. Reflection does not involve energy transfer to the underlying tissues but rather indicates that the laser is unable to penetrate due to the properties of the surface it encounters. This characteristic can influence the effectiveness of laser treatments depending on tissue types and conditions.