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:
Mar. 04, 2008
Filed:
Oct. 11, 2005
Xuehua Wu, Union City, CA (US);
Mingjun Zhao, Fremont, CA (US);
John Feng, Union City, CA (US);
Avanex Corporation, Fremont, CA (US);
Abstract
The present invention describes a structure and method for a multi-ports WDM device for compensating the filter distortion while reducing insertion loss. The multi-ports WDM device comprises a 4-fiber collimator having a grin lens and a 2-fiber collimator having a lens where the focal plane of the second lens is shorter than the focal plane of the first grin lens Ands with aspheric surface. When a light signal travels through the first lens in the 4-fiber collimator to a filter, the film on the filter causes distortion to the light signal resulting in a large insertion loss. To compensate for the insertion loss, the lens on the 2-fiber collimator has a aspheric function and a shorter focal plane than the grin lens on the 4-fiber collimator. The type of grin lens used in the 4-fiber collimator is different than the lens used in the 2-fiber collimator. Effectively, the lens in the 2-fiber collimator operates to de-focus a light signal relative to the grin lens in the 4-fiber collimator.