Magnetic field measuring device and optical frequency modulator

Abstract

Abstract PURPOSE:To obtain relatively small-sized constitution and take a high-precision measurement by measuring the difference frequency between a clockwise and a counterclockwise polarized wave projected from either one of reflecting mirrors respectively. CONSTITUTION:A semiconductor laser 1 is provided with the reflecting surfaces (reflecting mirror) 2 and 3 constituting an external resonator. Then, a lambda/4 plate 4 is provided in front of the reflecting surface 2, and a Faraday rotator 5 and a lambda/4 plate 6 are arranged in front of the reflecting surface 3. Two kinds of light passed through the Faraday rotator 5, i.e. a TE wave and a TM wave projected to the right side of the semiconductor laser 1 are circularly polarized waves differing in rotational direction. Those circularly polarized light waves have a difference in the passing time of the Faraday rotator 5 having constant thickness, so the distance between the reflecting surfaces 2 and 3 is different apparently between the two kinds of light, so that those light waves have different resonance frequencies. A means which controls and varies an applied magnetic field is provided to constitute an optical frequency modulator.

Inventors

• 👤 Masataka Shirasaki
• 👤 白崎　正孝
• 👤 Hiroki Nakajima
• 👤 啓幾 中島
• 👤 Yasuo Furukawa
• 👤 古川　泰男
• 👤 Yushi Inagaki
• 👤 雄史 稲垣

Bibliographic Details