The Furukawa Electric Co., Ltd.

Hideo Aoyagi

Takeo Shimizu

Yuichiro Irie

Yutaka Ohki

Etsuji Katayama

Kiyofumi Muro

Takeharu Yamaguchi

Naoki Hayamizu

Takeshi Koiso

Toshiaki Tsuda

Yuji Yamagata

A laser module includes a semiconductor laser element and a feedback optical component forming an external cavity with the semiconductor laser element. Even if a ratio of a current threshold of the laser module changing according to a polarized state of returned light from the feedback optical component to a current threshold of the semiconductor laser element is in an arbitrary range within a predetermined range, a total value of a relative intensity noise occurring between a first frequency determined according to a cavity length of the external cavity and at least equal to or more than a frequency band of using a laser light and a second frequency calculated by multiplying the first frequency by a predetermined number is equal to or more than &#x2212;40 dB.

Laser module

An optical amplifier of the present invention comprises a pumping light source configured to output a pumping light, an amplifier unit configured to receive the pumping light from said pumping light source and amplify an optical signal that passes therethrough, and an optical fiber disposed between said pumping light source and said amplifier unit, said optical fiber including an optical filter that is configured to attenuate the optical signal from said amplifier unit.

Optical amplifier, light source module and optical system

Growing community of inventors

Tokyo, Japan

Hideo Aoyagi