Nippon Telegraph and Telephone Corporation

Ntt Electronics Corporation

Katsuaki Magari

Osamu Tadanaga

Yoshiki Nishida

Masaki Asobe

Tsutomu Yanagawa

Yasuhiro Suzuki

Hiroyuki Suzuki

Hiroshi Miyazawa

Toshio Ito

Takeshi Umeki

Hiromi Oohashi

Hiroyasu Mawatari

Junji Yumoto

Hiroyuki Kamioka

A wavelength converter which performs simultaneously wavelength conversion for a plurality of input light wavelengths that are unequally intervals, is provided. The nonlinear material of the wavelength converter has a modulation structure which has modulation of a nonlinear optical constant at a period &#x39b;in a propagating direction of light, a phase being continuously changed each period &#x39b;and a continuous phase modulation for a different period &#x39b;being added to the modulation structure. The nonlinear material has a modulation structure obtained by changing a modulation curve for the phase modulation, wherein a phase mismatch &#x394;&#x3b2; is represented by &#x394;&#x3b2;=2&#x3c0;(n/&#x3bb;&#x2212;n/&#x3bb;&#x2212;n/&#x3bb;), and at least three peaks at unequally intervals within a plurality of peaks for conversion efficiency represented by 2&#x3c0;/&#x39b;+2&#x3c0;i/&#x39b;(i=m, m+1, . . . , n: where m and n are positive or negative integers) have highest conversion efficiency.

Wavelength converter and wavelength conversion apparatus

A light source apparatus with modulation function has a wavelength conversion module () composed of a nonlinear optical material with a structure having a nonlinear constant modulated periodically. It outputs a difference frequency or sum frequency produced by multiplexing pumping light from semiconductor laser light sources () and () with different wavelengths through a WDM coupler () and by launching the multiplexed light into the optical waveguide. The semiconductor laser light source () includes a diffraction grating. The semiconductor laser light source () includes a section for modulating output light emitted from its semiconductor laser, and is connected to an external FBG () which has a reflection band narrower than a resonance wavelength spacing determined by the device length of the semiconductor laser. The FBG () is supplied with the modulated output.

Light source apparatus with modulation function and its driving method

In an SOA characteristic evaluation method, the current is supplied to an SOA. An optical output generated by the SOA that have received the current is measured. Transmission light obtained by transmitting the optical output through a wavelength filter and/or a polarizer is measured. The characteristic of the SOA is evaluated on the basis of the measurement result of the optical output and the measurement result of the transmission light without using an optical input to the SOA. An SOA characteristic evaluation apparatus is also disclosed.

Semiconductor optical amplifier characteristic evaluation method and apparatus

Growing community of inventors

Atsugi, Japan

Katsuaki Magari