| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical module having characteristics of small-sizing and high extinction ratio appropriate for an optical isolator to be used for a high-output laser such as an e.g., fiber laser which is used for laser processing or the like. <P>SOLUTION: An optical module comprises a Faraday rotator of which the Verdet constant in waveform 1.06 μm is 0.27 min/(Oe cm) or more and a hollow magnet which is disposed in the outer circumference of the Faraday rotator. A magnetic flux density B(Oe) applied to the Faraday rotator is settled within the range of an inequality (1) 0.5×10<SP POS="POST">4</SP>≤B≤1.5×10<SP POS="POST">4</SP>. A sample length L(cm) and an outer diameter D(cm) with which the Faraday rotator is disposed are settled within the ranges of inequalities (2) 0.70≤L≤1.10 and (3)0.20≤D≤0.60. Further, in the optical module, the Faraday rotator is formed cylindrical, meets the dimensions of (2) and (3) and has an insertion loss of 1 dB or less and an extinction ratio of 35 dB or more. <P>COPYRIGHT: (C)2013,JPO&INPIT |
