The physical interaction between two or more systems, also known as coupling, can give rise to unique and unexpected effects. In the field of optics, coupled light sources (e.g., lasers) can influence each other, producing complex light patterns that cannot be emitted by individual light-emitting systems. The physical interaction between two or more systems, also known as coupling, can give rise to unique and unexpected effects. In the field of optics, coupled light sources (e.g., lasers) can influence each other, producing complex light patterns that cannot be emitted by individual light-emitting systems. Optics & Photonics Phys.org – latest science and technology news stories