News Column

Patent Issued for Single-Mode Optical Fibers for Optical Fiber Connectors

July 16, 2014



By a News Reporter-Staff News Editor at Telecommunications Weekly -- From Alexandria, Virginia, VerticalNews journalists report that a patent by the inventors Li, Ming-Jun (Horseheads, NY); Peng, Gaozhu (Horseheads, NY); Saravanos, Constantine (Highland Village, TX), filed on March 30, 2012, was published online on July 1, 2014.

The patent's assignee for patent number 8764311 is Corning Cable Systems LLC (Hickory, NC).

News editors obtained the following quote from the background information supplied by the inventors: "Optical fiber connectors are used in a variety of telecommunications applications to connect one optical fiber to another, or to connect an optical fiber to a telecommunications device. Certain optical fiber connectors such as mechanical splice connectors include a short section of single-mode optical fiber (SMF) called a stub fiber that interfaces with a field optical fiber that is inserted into the connector in the field by the end-user. When a connector is operably connected (mated) to another connector, the stub fiber resides between the field fiber of its own connector and the stub fiber of the mating connector.

"When all the optical fibers are aligned and otherwise matched in size and configuration, the light travels in the field and stub fibers in the lowest or fundamental mode, namely the LP.sub.01 mode. However, a misalignment, a mismatch in the mode-field diameter (MFD) of the fibers, or a combination of these and other factors, can cause light to travel in higher-order modes, such as the LP.sub.11 mode for a short distance even though the fibers are SMFs. Thus, though an optical fiber may be designed to be an SMF, there are circumstances under which they operate as multimode optical fibers.

"Coherent light traveling in different guided modes takes different optical paths and can cause multi-path interference (MPI). MPI can cause light transmitted through the connector to have significant time-dependent fluctuations that are exacerbated by the use of off-the-shelf SMFs designed for long-haul telecommunications applications. MPI and the attendant power fluctuations are undesirable and degrade the performance of the telecommunications system in which the optical fiber connector is used."

As a supplement to the background information on this patent, VerticalNews correspondents also obtained the inventors' summary information for this patent: "Single-mode optical fibers suitable for use in optical fiber connectors as stub fibers are disclosed herein. The single-mode optical fibers have a fundamental mode (LP.sub.01) that substantially matches the mode field diameter of a standard SMF to reduce or minimize connector loss.

"An aspect of the disclosure is a single-mode optical fiber ('fiber') for use in an optical fiber connector having an operating wavelength .lamda.. The fiber includes a core having a radius r.sub.0, with a cladding immediately surrounding the core, with the core and cladding supporting a fundamental mode. The core and cladding define a relative refractive index profile .DELTA. that defines a cutoff wavelength .lamda..sub.C.ltoreq.1200 nm and a mode-field diameter MFD.sub.SN that is: a) between 8.2 .mu.m and 9.7 .mu.m when the operating wavelength .lamda.=1310 nm, and b) between 9.2 .mu.m and 10.9 .mu.m when the operating wavelength .lamda.=1550 nm.

"Another aspect of the disclosure is fiber for use in an optical fiber connector having an operating wavelength .lamda.. The fiber has a core having a radius r.sub.0, with a cladding immediately surrounding the core, wherein the core radius r.sub.0 is in the range from 3.5 .mu.m to 5.5 .mu.m. The core and cladding define a relative refractive index profile .DELTA. that defines a cutoff wavelength .lamda..sub.C.ltoreq.1200 nm and that has a maximum relative refractive index .DELTA..sub.0 in the range from 0.26 to 0.40%. The core and cladding also define a mode-field diameter MFD.sub.SN that is: a) between 8.2 .mu.m and 9.7 .mu.m when the operating wavelength .lamda.=1310 nm, and b) between 9.2 .mu.m and 10.9 .mu.m when the operating wavelength .lamda.=1550 nm.

"Another aspect of the disclosure is an optical fiber connector that utilizes the fiber as disclosed herein as a stub fiber. The connector has a first alignment member that operably supports the stub fiber, with the stub fiber having an end. The connector also includes a second alignment member that operably supports a single-mode field optical fiber such that the respective ends of the stub fiber and the single-mode field optical fiber are operably aligned and interfaced.

"These and other aspects of the disclosure will be further understood and appreciated by those skilled in the art by reference to the following specification, claims and appended drawings."

For additional information on this patent, see: Li, Ming-Jun; Peng, Gaozhu; Saravanos, Constantine. Single-Mode Optical Fibers for Optical Fiber Connectors. U.S. Patent Number 8764311, filed March 30, 2012, and published online on July 1, 2014. Patent URL: http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=8764311.PN.&OS=PN/8764311RS=PN/8764311

Keywords for this news article include: Telecommunications.

Our reports deliver fact-based news of research and discoveries from around the world. Copyright 2014, NewsRx LLC


For more stories covering the world of technology, please see HispanicBusiness' Tech Channel



Source: Telecommunications Weekly


Story Tools






HispanicBusiness.com Facebook Linkedin Twitter RSS Feed Email Alerts & Newsletters