The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 14, 1995
Filed:
Mar. 16, 1994
Tatsuyuki Fujita, Tokyo, JP;
Mikio Maeda, Tokyo, JP;
Toshiya Sato, Katsuta, JP;
Tsuneo Horiguchi, Mito, JP;
Ando Electric Co., Ltd., Tokyo, JP;
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
Abstract
An optical pulse tester capable of displaying Raman scattered light is disclosed. An optical pulse with the specified wavelength is injected into an optical fiber to be measured via a directional coupler and an optical demultiplexer/multiplexer. The demultiplexer/multiplexer demultiplexes returning light from the optical fiber into Raman scattered light different from the optical pulse in wavelength. The directional coupler divides returning light from the optical fiber into Fresnel reflection light and Rayleigh scattered light with the specified wavelength. The switcher supplies the Rayleigh scattered light to a display In the case of long distance measurement or precise loss measurement of the optical fiber. Therefore, the display displays the characteristic waveform of the optical fiber with the Rayleigh scattered light. In contrast, the switcher supplies the Raman scattered light to the display in the case of the measurement of the near-end part of the optical fiber or the connecting point between optical fibers without a dead area. Therefore, the display displays the characteristic waveform of the optical fiber with the Raman scattered light.