Sensor optical fiber

The invention relates to a fiber optic sensor for detecting an excitation near a whole optical fiber, said excitation inducing a modulation of the phase of an optical signal propagating in said optical fiber assembly, said sensor comprising: - a laser assembly (SL) emitting at least one laser beam; - an optical fiber assembly (OF); - an optical system configured to: ○ injecting at least a portion of said laser beam; ○ at least one signal generated laser beam from the injected laser beam and propagating in said fiber assembly; ○ generating at least one reference beam (Fr) from said laser beam and said signal beam; ○ performing at least one interference zone corresponding to the interference between a portion of the reference beam and a portion of the interference signal beam corresponding to the interference between a portion of the reference beam and a portion of the signal beam; - a set of digital holography comprising: ○ a spatial modulator of liquid crystal light; ○ a camera configured to receive said interference region and the electrically transcribed on said spatial light modulator of liquid crystal light in order to create a phase hologram corresponding thereto; - at least one optical detector configured to detect an output optical signal beam (Fout).