Faraday rotator and optical isolator based on this faraday rotator

Abstract

To provide a faraday rotator using a TGG ceramic sintered compact and a light isolator using the faraday rotator such that the influence of scattered light can be relatively reduced and overall characteristics degradation for the entire light isolator is minimized so that a high extinction ratio of at least 38 dB or greater is achieved. [Solution] The faraday rotator according to the present invention uses a TGG ceramic sintered compact having an average particle diameter of 0.2 to 5.0 μm, and has a transmission beam diameter of 0.3 mm or more, the TGG ceramic sintered compact being preferably annealed.

1 . A Faraday rotator comprising a TGG ceramics sintered compact having a mean grain diameter of 0.2-5.0 micrometers, wherein said Faraday rotator has a transmitted beam diameter of 0.3 mm or greater. 
     
     
         2 . The Faraday rotator as claimed in  claim 1 , characterized by that wherein said TGG ceramics sintered compact is subjected to an annealing treatment. 
     
     
         3 . The Faraday rotator as claimed in  claim 1 , wherein said ceramics sintered compact has an extinction ratio of at least 38 dB or higher. 
     
     
         4 . An optical isolator comprising a Faraday rotator as described in  claim 1 .