Multiple Optical Channel Autocorrelator Based on Optical Circulator

摘要

A multiple optical channel autocorrelator based on an optical fiber circulator includes a broad-band light source, at least an optical-fiber sensor array, an adjustable multiple light beams generator, at least an optical fiber circulator and at least a photoelectric detector. The optical-fiber sensor array is composed of the sensing fibers connected end to end. The in line mirrors are formed by the connecting end faces of the adjacent fibers. The adjustable multiple light beams generator includes a fixed arm and an adjustable arm. The optical path difference between the fixed arm and the adjustable arm is adjustable in order to match the optical path of each sensor in the sensor array. The optical fiber circulator couples the signals generated by the multiple light beams generator to the sensor array, and couples the signals returned by the sensor array to the photoelectric detector. The photoelectric detector is connected to the optical fiber circulator. The multiple optical channel autocorrelator based on the optical fiber circulator can implement the real-time in line measurement of the physical quantity of multipoint strain or deformation, and has advantages of low light source power loss, high efficiency and good stability.

主权项

1. A multiple optical channel autocorrelator based on optical fiber circulator for sensing, characterized in that, comprising: a source for providing broad-band light, at least an optical-fiber sensor array, an adjustable multi-beam generator, at least an optical fiber circulator and at least a photoelectric detector;
the optical-fiber sensor array is composed of several sensing fibers with good end-cutting connected end to end, in line partial reflective mirrors are formed at the connecting end faces of the adjacent fibers and mirrors of each part reflect part of reference light and sensing light; the adjustable multiple light beams generator includes a fixed arm and an adjustable arm, an optical path difference between the fixed arm and the adjustable arm is adjustable in order to match the optical path of each sensor in the sensor array; the optical fiber circulator couples signals generated by the dual-beam the multi-beam generator into the sensor array, and couples signals returning from the sensor array into the photoelectric detector; the photoelectric detector is connected to the optical fiber circulator, for detecting interference signal, wherein, the optical-fiber sensor array is composed of N optical-fiber sensors connected end to end in series, the in line partial reflective mirrors are formed at the connecting ends of the adjacent fibers, wherein N is a positive integer larger than 2, Wherein, the adjustable multi-beam generator is based on a structure of optical fiber Michelson interferometer and includes an optical fiber coupler, a fixed mirror, GRIN lens and a scanning mirror; sticking the mirror at the end face of c port of the optical fiber coupler forms a part of the sensing arm with a fixed optical path; serving as part of the reference arm, an end face of d port of the optical fiber coupler is connected to GRIN lens, for receiving optical signals reflected by the scanning mirror; the scanning mirror is installed on a linearity shift platform, and enables its reflecting surface to be perpendicular to the optical axis of the GRIN lens, such that an adjustable match distance is obtained between the GRIN lens and the scanning mirror; b port of the optical fiber coupler is connected to a port of the optical fiber circulator, b port of the optical fiber circulator is connected to the sensor array through input/output optical fiber; photoelectric detector is connected to c port of the optical fiber circulator; optical source is connected to optical fiber coupler through an optical fiber isolator.