The invention belongs to the technical field of optical fibers, and particularly relates to a multi-path 
optical path correlator with adjustable 
resonance cavity length, which is applied to a 
multiplexing optical fiber white light interference 
sensor array demodulation system. An 
optical resonance cavity is connected with an 
optical fiber light path by a coupler, the length of the 
resonance cavity is adjusted, the multiple travel of the 
optical path is performed, the multi-path 
optical path correlator consists of an 
optical resonance cavity with adjustable optical path, an 
optical fiber coupler, and a three-port or four-port optical 
fiber circulator, and the adjustable optical path difference 
signal can be generated by the reciprocating oscillation of the 
optical resonance cavity; a 
light signal containing the multi-path optical path difference is outputted by the coupler; the traveling direction of the 
light source is controlled by the three-port 
circulator, and the optical path correlation is performed through the connection with a light path of an optical 
fiber white light interface 
system. The multi-path optical path correlator has the advantages that the light path matching of multiple optical paths is realized, the 
demodulation capability of a 
sensing system is improved, the light path structure of the optical 
system is simplified, the system cost is reduced, and the stability and reliability of the system are improved.