The invention discloses an
optical fiber acoustic atomic force probe structure and a preparation method, and belongs to the technical field of optical micro-nano sensor preparation. One end face of the connecting diaphragm is fixed at one end of the single-mode
optical fiber, the acoustic
grating array is connected with the other end face of the connecting diaphragm through a plurality of supporting columns, the connecting diaphragm, the supporting columns and the acoustic
grating array form a Fabry-Perot cavity, the Fabry-Perot cavity is integrated on the end face of the
optical fiber and is obtained through 3D printing, and an environment medium is arranged in the cavity; the acoustic
grating array is a cone-shaped body formed by arranging a series of circular diaphragms with gradually increased radiuses and the same thickness along a central shaft at equal intervals. External
sound pressure acts on the conical acoustic grating array, when the
audio frequency is high, the inherent structural characteristic frequency of part of acoustic gratings is in a high-frequency range, the cavity drives the diaphragm to generate
large deformation along with the acoustic gratings, ultrasonic
signal detection is achieved by detecting interference
light intensity changes, and the atomic force probe structure can achieve
broadband high-frequency ultrasonic
signal detection. The sensitivity at the resonant frequency is high, and high-frequency weak ultrasonic signals can be accurately captured.