Optical isolation is a technique used to prevent unwanted light from interfering with sensitive optical systems. It typically involves the use of devices like optical isolators, which allow light to pass in one direction while blocking it in the opposite direction. This is crucial in applications such as lasers, where feedback can destabilize the output. By ensuring that light travels only in the intended direction, optical isolation helps maintain the performance and reliability of optical devices. It is commonly used in telecommunications, fiber optics, and various scientific instruments to protect against noise and reflections that could disrupt signal integrity.