PURPOSE: To suppress the frequent occurrence of strain of an optical device at the time of sticking to a metal as small as possible by arraying to form metallized pattern in a concentric circular state at the outer circumference of the optical device except a light transmitting part in a metallizing treatment for adhesion-fixing metal to the optical device for an optical isolator.

CONSTITUTION: Gadolinium.gallium.garnet is used as a magneto-optical device and a polar core is used as a pair of polarizer. Both are worked into a disk-like shape and the metallized patterns 2 are at positions made by dividing the circumference, which is described concentric on the disk of optical device 1 and has a prescribed diameter, into eight equal parts and are circular. The optical isolator is formed by soldering these optical devices 1. In this case, by regulating the total area of the metallized pattern of 5-20% of the area of the optical device 1, sufficient adhesive strength is attained and the characteristic deterioration caused by the strain of the optical device 1 is suppressed.