Patent ID: 7898720
Filing Date: 2011-03-01
Classification: G02F

Abstract:
1. A Faraday rotator which comprises a magnet member having at its center a through-hole through which light is to pass and a Faraday element comprising a paramagnetic material which is disposed inside the through-hole and through which the light is to be transmitted, wherein; the magnet member is constituted of a first magnet standing magnetized in the direction of magnetization that is perpendicular to the optical axis and the direction taken toward the optical axis, a second magnet standing magnetized in the direction of magnetization that is perpendicular to the optical axis and the direction taken against the optical axis, and a third magnet disposed between the first magnet and the second magnet and standing magnetized in the direction of magnetization that is parallel to the optical axis and the direction taken toward the first magnet from the second magnet; hollow spaces constituting the through-hole of the magnet member are provided at the centers of the first and second magnets and third magnet; the Faraday element is disposed at a central portion in the length direction of the through-hole constituted of these hollow spaces; and, where the length of the first magnet and that of the second magnet in the optical-axis direction are both represented by L