Patent ID: 11971617
Assignee: NIPPON ELECTRIC GLASS CO., LTD.
Field: Optics (Instruments)
Classification: CPC G  C | IPC C  G

Claim 0:
1. A Faraday rotator comprising:
a magnetic circuit including first to third magnetic materials each provided with a through hole through which light passes; and
a Faraday element disposed in the through hole and made of a paramagnetic material capable of transmitting light therethrough,
wherein the magnetic circuit is formed by coaxial arrangement of the first to third magnetic materials in this order in a front-to-rear direction,
when a direction where light passes through the through hole in the magnetic circuit is defined as a direction of an optical axis, the first magnetic material is magnetized in a direction perpendicular to the direction of the optical axis to have a north pole located toward the through hole, the second magnetic material is magnetized in a direction parallel to the direction of the optical axis to have a north pole located toward the first magnetic material, and the third magnetic material is magnetized in a direction perpendicular to the direction of the optical axis to have a south pole located toward the through hole, and
a length of the Faraday element along the direction of the optical axis is not less than 0.5 times but not more than 0.9 times a length of the second magnetic material along the direction of the optical axis.