Light pulse tester

Abstract

Abstract PURPOSE:To eliminate completely an effect of rear scattered light caused when a light source of intense interfering property is used, by detecting polarized wave elements of rear scattering light beams in two directions and composing both polarized wave elements. CONSTITUTION:Pulse light beam 6 emitted from a light source 5 is introduced into a Faraday rotating element 13 through parallel lens 4 and direction coupling element 14 and after 45 deg. rotation of its polarized wave axis, it is directed onto a specimen optical fiber 1. And, the rear scattering light beams 7, upon returning from the specimen fiber 1, are introduced into the directional coupling element 12 through a convergent lens 2 and a delta-axis polarized wave element 16 is introduced into an optical detector 20. Further, a gamma-axis polarized wave element, when passing through a Faraday rotator 13, is rotated by 45 deg. with respect to the polarizing axis to become rear scattering beams 18 parallel to the polarizing axis beta and its optical path is polarized by the directional coupling element 14 to be introduced into an optical detector 21. Consequently, the overall power of rear scattering light beams are generated always from an electrical composite circuit 22 regardless of polarization condition of the rear scattering light beams.

Inventors

• 👤 Yasuyuki Kato
• 👤 康之 加藤
• 👤 Mitsuru Miyauchi
• 👤 宮内　充
• 👤 Akihiko Ishikura
• 👤 石倉　昭彦

Bibliographic Details