Optical isolator

Abstract

Abstract PURPOSE:To miniaturize the structure of an optical isolator, by improving the uniformity of a magnetic field and obtaining a ferromagnetic field with use of the flat plate permanent magnets opposite to each other and at the same time increasing the optical path length by reflecting repetitively the light in a Faraday effect element. CONSTITUTION:Permanent magnets 1 and 2 are used, and a Faraday effect element 4 is set between the magnets 1 and 2. The element 4 is substantially trapezoidal. A reflecting multilayered film 3 is coated over the areas opposite to the upper surface, both surfaces and the bottom upper surface of the element 4 respectively. At the same time, a beam splitter 5 is connected to an upper end part of the element where no film 3 is applied, and a right-angled prism 6 is connected to the other end part of the element 4. Thus an optical isolator is obtained. With this isolator, the light 7 made incident from the left side in the figure is applied to the element 4 through the splitter 5 and travels to the right side while repeating the reflection on the upper bottom surface of the element 4. Then the light with which the polarized wave face has 45 deg. rotation is radiated unrevesely through the prism 6.

Inventors

• 👤 Satoru Amano

Bibliographic Details