Electric field displacing type optical isolator - includes dielectric light guide parallel to dielectric substrate with thin magnetic film

摘要

A glass substrate (7) is provided with a light guide (1) and a thin film (2) magnetised in direction shown (3). A resistance body (8) is formed on film (2). Light rays propagating through the light guide downwards have an electric field distribution which is inclined towards the side of the light guide opposite film (2), and travel with little absorption. Rays perpendicular to this are absorbed by thin film (2) and resistance body (8). The device is very efficient at absorbing rays in undesired directions and is utilised in optical integrated circuits.