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:
Apr. 11, 1995
Filed:
Dec. 30, 1993
Kokusai Denshin Denwa Kabushiki Kaisha, Tokyo, JP;
Abstract
A chromatic dispersion measuring method and apparatus are disclosed which permit highly accurate measurements of the wavelength dispersion characteristic of an optical transmission such as an optical fiber or an optical amplifier repeater system. Measurements are made on the propagation time of a first optical signal of a fixed wavelength through an optical transmission line to be measured and the propagation time through the same optical transmission line of a second optical signal whose wavelength can be arbitrarily set over the measuring wavelength band. By obtaining a difference between the both propagation times, it is possible to obtain only a change in the propagation time of each signal which is caused by a change in the wavelength of the second optical signal. That is, the elongation or shrinkage of the optical fiber has an equal influence on both of the first optical signal and the second optical signal, and hence does not induce an error in the detection of the above-said time difference.