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. 19, 2002
Filed:
Dec. 28, 1999
Yun-Chur Chung, Daejeonkwangyeok, KR;
Jin-Hwan Jang, Daejeonkwangyeok, KR;
Seung-Kyun Shin, Daejeonkwangyeok, KR;
Hoon Kim, Goyang, KR;
Keun-Joo Park, Molopo, KR;
Kwan-Seop Lee, Incheonkwangyeok, KR;
Samsung Electronics Co., Ltd., Suwon, KR;
Abstract
A cold-start wavelength-division-multiplexed (WDM) optical transmission system uses a synchronized etalon filter, DFB lasers and passive optical demultiplexers. The DFB lasers are tested under normal operating conditions and wavelength-selected for each channel. The wavelength selection is such that the laser operates within one half of the channel spacing from the standardized wavelength. For the cold-start operation, each laser is able to automatically find its operating wavelength without any prior knowledge of its operating conditions for the standardized wavelength. In addition, this system simultaneously adjusts the output power of each laser to a desired value. Also provided is a method for generating standardized frequencies for a wavelength-division-multiplexed optical transmission system, including the step of adjusting the incident angle of an etalon filter by employing two frequency-locked lasers to compensate for differences of the thickness and refractive index of the etalon filter, and the step of fixing the position of the etalon filter to permanently have the adjusted incident angle, the etalon filter having resonant frequencies respectively corresponding to standardized frequencies.