Patent attributes
A light-emitting device having a ring optical resonator and capable of laser oscillation by a novel structure realized by working out the mechanism of light emission. The light-emitting device having a ring optical resonator fabricated on a base is characterized in that the optical resonator has a core made of a semiconductor and serving to propagate light and a clad formed on at least the base side of the core in the stack direction out of the base side and the opposite side of the core, at least the ring inner and outer peripheral surfaces of the core are covered with a transparent body having an index of refraction lower than that of the space or the clad, and a part of the ring inner and outer peripheral surfaces of the clad are covered with a transparent body having an index of refraction lower than that of the space or the clad.