närfältsregionen
The närfältsregionen, often translated as the near-field region, is a concept used in physics, particularly in electromagnetism and acoustics, to describe the area close to a radiating source. It is contrasted with the far-field region, which is the area significantly distant from the source. The characteristics of waves and their propagation behave differently in these two regions.
In the context of electromagnetism, the near-field region is where the electric and magnetic fields are strongly
For acoustic waves, the near-field region is where the pressure and velocity components of the wave are
The transition between the near-field and far-field is not always sharply defined and depends on the wavelength