High-sensitivity fiber-compatible optical acoustic sensor

An acoustic sensor includes at least one photon crystal structure which has at least one optical resonance with resonance frequency and resonance alignment. An acoustic sensor surrounds at least one photon crystal structure substantially, and contains further the housing mechanically combined with at least one photon crystal structure. At least one of resonance frequency and the resonance alignment answers the sound wave which enters into a housing. [Chosen drawing] Drawing 1