Fdk Corporation

Masaharu Hoshikawa

Hiromitsu Umezawa

Mikio Kitaoka

Yuji Goto

Takashi Kato

Tsugio Tokumasu

Toshihiko Watanabe

Akitoshi Mesaki

Chiharu Nishida

It is possible to reduce the size of a magneto-optical device, increase the speed of optical control, simplify power supply structure and its control, and maintain a Faraday rotation angle in an arbitrary state even after shut-off of the excitation current. The magneto-optical device includes a magnetic yoke () made of a high-permeability magnetic material, the magnetic yoke including a tabular portion () and four pillar portions () protruding from one side of the tabular portion (), a coil () wound on each of the pillar portions, and a magneto-optical element () arranged in an open-magnetic-circuit region surrounded by the end portions of the four pillar portions. A magnetic field obtained by a coil is applied to the magneto-optical element.

Magneto-optical device

A polarized-light separating/combining element is obtained which can suppress deviation in a direction of rays (angular error), reduce beam coupling loss and improve extinction ratio. Size reduction and loss lowering is achieved for an optical device (optical circulator or optical switch), to enable manufacture at a low cost and with ease. A polarized-light separating/combining element has a transparent member having flat surfaces parallel with each other on which both parallel surfaces, polarized-light separating/combining films are formed respectively, wherein both polarized-light separating/combining films are faced to air. By using the polarized-light separating/combining element, various kinds of optical devices (optical circulators or optical switches) can be formed. Particularly, it is effective for realizing a low crosstalk characteristic in a matrix optical switch.

Polarization separating/synthesizing element and optical device using it

Growing community of inventors

Minato-ku, Japan

Masaharu Hoshikawa