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:
Jun. 11, 2002
Filed:
Oct. 05, 2000
Applicant:
Inventors:
Assignee:
Tera Fiberoptics, Inc., Fremont, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04J 1/400 ; H04J 1/402 ; H04B 1/020 ; G02B 6/28 ;
U.S. Cl.
CPC ...
H04J 1/400 ; H04J 1/402 ; H04B 1/020 ; G02B 6/28 ;
Abstract
System and method for wavelength discrimination using a DWDM (N+1)-stage fiber optic cascade tree structure with additional filtering to provide acceptable flat-top passband response, and to provide acceptable optical isolation when combined with a multilayer thin film filter. Each channel in a DWDM cascade tree structure has a conventional Mach-Zehnder interferometer (MZI) that provides wavelength discrimination. Each channel in at least one stage has an additional filter that is either (1) an inverted Fabry-Perot etalon (FPE) or (2) an inverted, non-symmetric MZI. The number of output channels may be 32, 64, 128 or more.