A symmetric figure-of-eight optical fiber resonator

A theoretical study is presented of a figure-of-eight optical fiber resonator that has two single-mode couplers. The output intensities of the optical fiber resonator are investigated in terms of the coupling coefficients and losses. The finesse and contrast are discussed. Compared with a transversely coupled fiber Fabry–Perot resonator, this resonator has an all-fiber configuration, and is more easily realized. Compared with a direct-coupling fiber ring resonator, it offers reflected outputs that may be useful in some applications.