To provide a sound collecting apparatus collecting the sonic waves while improving a detection efficiency of sonic waves.
A sound collecting apparatus 1 comprises: a horn unit 3 including a horn body formed into a hollow tubular shape wherein an area of one of both opening end faces is wider than an area of the other end face, and a vibrating film spread over an inner wall in the vicinity of one end face of the horn body so as to close the relevant one end face; an optical fiber 5 passed through a center of the vibrating film of the horn unit 3 and supported between the relevant vibrating film and a fixed portion bonded to an inner wall in the vicinity of the other end face of the horn unit 3; optical fiber Bragg grating 7 provided between the vibrating film and the fixed portion for emitting reflection light with vibration as distortion; an optical fiber distortion measuring means 9; and a conversion device 11.
KUROZUMI KOICHI
TANABE ITSUO
Etsuo Tada