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. 27, 2000
Filed:
Nov. 03, 1997
Peter Z Chen, Fremont, CA (US);
Applied Fiber Optics, Inc., Fremont, CA (US);
Abstract
A structure and method are provided to compensate for temperature changes on wavelength shifting in DWDM by reducing tension in a fused-fiber DWDM when temperature increases and increasing tension when temperature decreases, thereby stabilizing wavelength shifts throughout the range of operating temperatures. The DWDM, which is enclosed by a protective package in some embodiments, is connected to substrates of different thermal expansion coefficients, such that the fused-fiber portion of the DWDM exhibits negative thermal expansion, i.e. contracts when temperature increases and expands when temperature decreases. As a result, temperature-induced wavelength shifts are minimized due to a passive thermal compensation, which can be easily adjusted. In other embodiments, twisting the fused-fiber portion of the DWDM to obtain optimum phase matching minimizes the polarization-dependent losses in the incoming light.