JPS6480926A - Optical isolator - Google Patents

Abstract

PURPOSE:To load the optical isolator compactly in the same package with other optical devices by employing an electromagnet which uses a superconducting coil as a magnetic field producing means. CONSTITUTION:The optical isolator equipped with a Faraday element 2 and the magnetic field producing means which applies a magnetic field to the Faraday element 2 employs the electromagnet 1 which uses the superconductive coil as the magnetic field producing means. The optical isolator is therefore reducible in size greatly and the optical isolator generates a little heat, so any adverse influence of heat is not exerted upon electrooptic components such as a semiconductor laser chip. Consequently, the optical isolator can be mounted with high density together with other devices such as a semiconductor laser chip, an optical integrated circuit, and an optical fiber which have characteristics affected sensitively by temperature.