A new torque instrument driven by light power with two rings

This paper introduces a non-contact torque instrument driven by light power with two rings and circuits of micro-dissipated power. The instrument implements a non-contact signal coupling and a non-contact power supply is needed by the probe of the instrument in torque measurement. The instrument, driven by indoor natural light or the light transmitted through an optical fiber can carry out on-line measurement continuously. It is particularly suitable for inflammable and explosive environments application.<>