FIBER OPTIC SENSOR FOR POSITION SENSING

摘要

A system for sensing the position of a movable object includes a polarization maintaining fiber configured to receive light from a light source; an optical system configured to rotate an angle of polarization of the light by a first predetermined angle; a low birefringence fiber connected to the optical system at a first end and having a mirror connected to a second end configured to reflect the light and rotate the angle of polarization at a second predetermined angle, the second end being configured to overlap a magnetic field of the a magnet attached to the object. The angle of polarization is rotated to a third predetermined angle proportional to at least one of the strength of the magnetic field and an amount of the overlap. The optical system is configured to decompose the third predetermined angle into a first component and a second component. A detector is configured to detect a differential between the first and second components indicative of the amount of the overlap.

主权项

1. A system for sensing the position of a movable object having a first magnet attached to the object, comprising:
a polarization maintaining fiber configured to receive light from a light source; an optical system configured to rotate an angle of polarization of the light by a first predetermined angle; a low birefringence fiber connected to the optical system at a first end and having a mirror connected to a second end configured to reflect the light and rotate the angle of polarization at a second predetermined angle that is twice the first predetermined angle, the second end being configured to overlap a magnetic field of the first magnet at at least one position of the movable object, wherein the angle of polarization will be rotated to a third predetermined angle proportional to at least one of the strength of the magnetic field and an amount of the overlap, and the optical system is configured to decompose the third predetermined angle into a first component and a second component; and a detector operatively connected to the optical system configured to detect a differential between the first and second components indicative of the amount of the overlap.