BRILLOUIN RING LASER

摘要

BRILLOUIN RING LASER A Brillouin ring laser comprises a length of optical fiber having first and second end portions and forming a loop portion between the end portions. A fiber optic coupler is used to optically close the loop portion. The length of the loop portion and the coupling constant of the coupler are selected to form a resonant cavity. A light source introduces pump light into the first end portion to provide a pump light wave which propagates through the loop portion. The pump light wave circulates through the resonant cavity and increases in intensity to a level which is greater than the intensity of the pump light in the first end portion. The intensity level in the resonant cavity is sufficient to cause stimulated Brillouin scattering in the fiber loop portion to provide a Brillouin wave which circulates through the fiber loop portion in a direction opposite to that of the pump light wave, and is shifted in frequency relative to the pump light wave.