Abstract: An optical isolator includes a first optical collimator, an isolated core, a second optical collimator and an outer tube. The first and second collimators and the isolated core are accommodated in the outer tube. The second collimator has a long sleeve which entirely accommodates the isolated core. The isolated core includes a first polarizer, a Faraday rotator crystal, and a second polarizer positioned in sequence within a toroidal magnetic core. An axial length of the toroidal magnetic core is equal to or slightly less than an overall length of the two polarizers and the rotator crystal. The two polarizers and the rotator crystal are sized such that an overall diameter of the isolated core is less than an inner diameter of the long sleeve. The magnetic core is glued within the long sleeve.

Abstract: An optical isolator includes a first optical collimator, an isolated core, a second optical collimator and an outer tube. The first and second collimators and the isolated core are accommodated in the outer tube. The second collimator has a long sleeve which entirely accommodates the isolated core. The isolated core includes a first polarizer, a Faraday rotator crystal, and a second polarizer positioned in sequence within a toroidal magnetic core. An axial length of the toroidal magnetic core is equal to or slightly less than an overall length of the two polarizers and the rotator crystal. The two polarizers and the rotator crystal are sized such that an overall diameter of the isolated core is less than an inner diameter of the long sleeve. The magnetic core is glued within the long sleeve.