Patent ID: 6594068
Filing Date: 2003-07-15
Classification: G02F

Abstract:
An optical Faraday rotator comprising:an iron-garnet based magneto-optic crystal for transmitting a light beam therethrough wherein said magneto-optic crystal having bi-stable magnetization states with hysteresis coercivity greater than 10 Oe; a switching device comprising coil windings around said magneto-optic crystals; a switching circuit connected to said switching device wherein said switching circuit includes a pulse current generating means having a capacitor for generating a pulsed current of a first polarity in charging said capacitor and a pulsed current of a second polarity opposite the first polarity in discharging from said capacitor for providing a pulse current with rapid rise and fall time; said pulsed current of said first and second polarities are converted by said switching device into magnetic field of a corresponding first and second polarities for switching the saturated bi-stable magnetization state of said magneto-optic crystal; and said magneto-optic crystal is provided for rotating a polarization of said light beam transmitted therethrough depending on said saturated bi-stable magnetization state of said semi-hard or hard magneto-optic crystal.