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:
Jul. 30, 2002
Filed:
Jul. 10, 2001
Tomoyu Yamashita, Saitama, JP;
Advantest Corporation, Tokyo, JP;
Abstract
The object of the present invention is to provide an apparatus that can perform measurement of chromatic dispersion, even if the wavelength of variable-wavelength light source and that of fixed-wavelength light source for reference are identical with each other. The variable-wavelength light generated by a variable-wavelength light source is subjected to intensity modulation to a frequency f by a first optical modulator and transmitted from one end to the other end of an optical fiber The fixed-wavelength light generated by a fixed-wavelength light source is subjected to intensity modulation to a frequency f by a second optical modulator and transmitted from the other end to the one end of optical fiber Therefore, it is possible to separately obtain the variable-wavelength light and fixed-wavelength light transmitted through the optical fiber using a second directional coupler and a first directional coupler respectively, regardless of wavelengths thereof. Accordingly, it is also possible to perform the comparison of phase and measurement of chromatic dispersion, even if the wavelengths of variable-wavelength light source and fixed-wavelength light source for reference are identical with each other.