Optical fiber magnetic field sensor

Abstract

Abstract PURPOSE:To reduce a measurement error and to improve reliability by transmitting light beams at plural maximum output points with different wavelengths in the same optical path, and calculating errors of the influence of a magnetic field on those light beams. CONSTITUTION:This sensor is constituted of a light source 11 having peaks in two wavelengths of lambda1 and lambda2, an optical fiber 12, a polarizer means 13, a magnetooptic effect means 14, an analyzer means 15, an optical fiber means 16, etc. Light beams of lambda1 and lambda2 emitted from the light source 11 in this system are varied in level and supplied to a photodetecting means 17 as outputs P1 and P2 of light electric power. The photodetecting means 17 demultiplexes the two waves of the wavelengths lambda1 and lambda2 to detect their levels independently and the results are processed by an analog or digital arithmetic means 18 such as a microcomputer to find a magnetic field H. Thus, the measurement error is reduced and the reliability is improved.

Inventors

• 👤 Motoo Shimizu
• 👤 清水　基夫

Bibliographic Details