Discrete dipole approximation

The Discrete Dipole Approximation (DDA) is a numerical method used to model the scattering and absorption of electromagnetic waves by objects that are comparable in size to the wavelength of the radiation. This technique is particularly useful in studying the optical properties of particles like aerosols, biological cells, and nanostructures. In DDA, the object of interest is represented as an array of N point dipoles (or polarizable points).