| 摘要 |
A device for monitoring a magnetic field intensity having a given direction, the device including: a light conducting member (11) defining a first optical port (23), a second optical port (24), an optical path extending between the ports, and elements (31,34) for causing light to travel along the path between the ports (23,24); a first polarizer (31) disposed in the optical path for polarizing the light beam in a first plane of polarizaiton transverse to the path; a second polarizer (33) disposed in the optical path for polarizing the light beam in a second plane of polarization transverse to the path, the second polarizer (33) being spaced along the path from the first polarizer (31); and a focusing surface (18) disposed to intersect the beam at a point along the path between the polarizers (31,33) to focus the light beam from the first optical port (23) onto the second optical port (24). The light conducting member (11) constitutes a medium between the first and second polarizers (31,33) for permitting rotation of the plane of polarization of the light beam under influence of the magnetic field when the device is oriented so that at least a portion of the optical path between the polarizers (31,33) extends in a direction having a component parallel to the given direction so that the intensity of the light beam at the second optical port (24) will vary as a function of variations in the intensity of the magnetic field.
|
