Light isolator

Abstract

Abstract PURPOSE: To achieve the improvement in wavelength characteristics and temperature characteristics by interposing a magneto-optic material and an opticially active material between a pair of polarizers. CONSTITUTION: A magneto-optic material 1 such as YIG having Faraday effect and an optically active material 5 such as tellurium oxide having natural optical activity are interposed between a pair of polarizers 2, 3 disposed in mutually orthogonal positions. As a result, the light propagating in the direction of the arrow (a) is rotated 45° by the magneto-optic material 1 to which an external magnetic field is applied by a magnet 4 and 45° by the optically acitive material 5, by which its plane of polarization is rotated 90. The light propagating in the direction of the arrow (b) is then rotated 45° by the optically active material 5 and rotated -45° by the magneto-optic material 1, by which the rotation of its plane of polarization is made zero. Hence, it turns out that the light propagates in the (a) direction but not in the (b) direction. Owing to the introduction of the optically active material 5, only the difference of the change quantity of the rotatory power of the YIG and crystal affects the degradation of reverse loss and the temperature characteristics are improved by the combination of the YIG and tellurium oxide. COPYRIGHT: (C)1979,JPO&Japio

Inventors

• 👤 Hidetoshi Iwamura
• 👤 Shintaro Hayashi

Bibliographic Details