Optical waveguides – With optical coupler – Particular coupling function
Reexamination Certificate
2001-09-07
2003-04-01
Uliah, Akm E. (Department: 2874)
Optical waveguides
With optical coupler
Particular coupling function
C385S015000, C385S032000, C385S039000, C385S050000
Reexamination Certificate
active
06542663
ABSTRACT:
BACKGROUND
This application relates to optical fiber devices, and more specifically, to devices based on evanescent optical coupling between two fibers.
Optical waves may be transported through optical waveguiding elements or “light pipes” such as optical fibers. A typical fiber may be simplified as a fiber core and a cladding layer surrounding the fiber core. The refractive index of the fiber core is higher than that of the fiber cladding to confine the light. Light rays that are coupled into the fiber core within a maximum angle with respect to the axis of the fiber core are totally reflected at the interface of the fiber core and the cladding. This total internal reflection provides a mechanism for spatially confining the optical energy of the light rays in one or more selected fiber modes to guide the optical energy along the fiber core. Optical fibers may be used in transmission and delivery of optical signals from one location to another in a variety of optical systems, including but not limited to, fiber devices, fiber links and fiber networks for data communications and telecommunications. In addition, optical fibers may be used to form various optical devices to modify, filter, or process guided optical energy.
The guided optical energy in a fiber, however, is not completely confined within the core of the fiber. A portion of the optical energy can “leak” through the interface between the fiber core and the cladding via an evanescent field that essentially decays exponentially with the distance from the core-cladding interface. The distance for a decay in the electric field of the guided light by a factor of e≈2.718 is about one wavelength of the guided optical energy. This evanescent leakage may be used to couple optical energy into or out of the fiber core, or alternatively, to perturb the guided optical energy in the fiber core.
SUMMARY
According to one embodiment, a fiber device includes a substrate having first and second opposing substrate surfaces and including an elongated groove formed over the first substrate surface, and a fiber having a fiber coupling portion engaged in the elongated groove. A portion of fiber cladding of the fiber coupling portion is removed to form a side fiber surface spaced from a fiber core of the fiber within a reach of an evanescent field of a guided mode in the fiber. The fiber coupling portion has a fiber cladding portion whose radial index distribution is different from adjacent fiber portions to produce a radial mode profile wider than a radial mode profile of the adjacent fiber portions.
Methods for fabricating a fiber device are also provided. In one embodiment, a method includes selecting a fiber portion of a fiber, removing a portion of fiber cladding of the selected fiber portion to form a fiber coupling surface spaced from a fiber core of the selected fiber portion within a reach of an evanescent field of a guided mode, and modifying a property of said selected fiber portion. The modification increases a cladding refractive index of the selected fiber portion and to increase a spatial mode profile of said guided mode in the selected fiber portion to be greater than a spatial mode profile of the guided mode in an adjacent fiber portion whose cladding refractive index is not modified.
REFERENCES:
patent: 4021097 (1977-05-01), McMahon
patent: 4136929 (1979-01-01), Suzaki
patent: 4259016 (1981-03-01), Schiffner
patent: 4301543 (1981-11-01), Palmer
patent: 4302071 (1981-11-01), Winzer
patent: 4307933 (1981-12-01), Palmer et al.
patent: 4315666 (1982-02-01), Hicks, Jr.
patent: 4378539 (1983-03-01), Swanson
patent: 4392712 (1983-07-01), Ozeki
patent: 4431260 (1984-02-01), Palmer
patent: 4479701 (1984-10-01), Newton et al.
patent: 4493528 (1985-01-01), Shaw et al.
patent: 4536058 (1985-08-01), Shaw et al.
patent: 4556279 (1985-12-01), Shaw et al.
patent: 4560234 (1985-12-01), Shaw et al.
patent: 4564262 (1986-01-01), Shaw
patent: 4601541 (1986-07-01), Shaw et al.
patent: 4688882 (1987-08-01), Failes
patent: 4721352 (1988-01-01), Sorin et al.
patent: 4723827 (1988-02-01), Shaw et al.
patent: 4778237 (1988-10-01), Sorin et al.
patent: 4784453 (1988-11-01), Shaw et al.
patent: 4828350 (1989-05-01), Kim et al.
patent: 4842358 (1989-06-01), Hall
patent: 4869567 (1989-09-01), Millar et al.
patent: 4896932 (1990-01-01), Cassidy
patent: 4900118 (1990-02-01), Yanagawa et al.
patent: 4986624 (1991-01-01), Sorin et al.
patent: 4991922 (1991-02-01), Dahlgren
patent: 5029961 (1991-07-01), Suzuki et al.
patent: 5042896 (1991-08-01), Dahlgren
patent: 5100219 (1992-03-01), Takahashi
patent: 5329607 (1994-07-01), Kamikawa et al.
patent: 5444723 (1995-08-01), Chandonnet et al.
patent: 5533155 (1996-07-01), Barberio et al.
patent: 5586205 (1996-12-01), Chen et al.
patent: 5623567 (1997-04-01), Barberio et al.
patent: 5651085 (1997-07-01), Chia
patent: 5729641 (1998-03-01), Chandonnet et al.
patent: 5781675 (1998-07-01), Tseng et al.
patent: 5809188 (1998-09-01), Tseng et al.
patent: 5841926 (1998-11-01), Takeuchi et al.
patent: 5854864 (1998-12-01), Knoesen et al.
patent: 5892857 (1999-04-01), McCallion
patent: 5900983 (1999-05-01), Ford et al.
patent: 5903685 (1999-05-01), Jones et al.
patent: 5915063 (1999-06-01), Colbourne et al.
patent: 5940556 (1999-08-01), Moslehi et al.
patent: 5963291 (1999-10-01), Wu et al.
patent: 5966493 (1999-10-01), Wagoner et al.
patent: 5970201 (1999-10-01), Anthony et al.
patent: 6011881 (2000-01-01), Moslehi et al.
patent: 6026205 (2000-02-01), McCallion et al.
patent: 6038359 (2000-03-01), Moslehi et al.
patent: 6052220 (2000-04-01), Lawrence et al.
patent: 6058226 (2000-05-01), Starodubov
patent: 6130984 (2000-10-01), Shen et al.
patent: 6134360 (2000-10-01), Cheng et al.
patent: 6144793 (2000-11-01), Matsumoto et al.
patent: 6185358 (2001-02-01), Park
patent: 6453102 (2002-09-01), Dong et al.
patent: 28 12 346 (1978-03-01), None
patent: 0178045 (1986-04-01), None
patent: 2613844 (1988-10-01), None
patent: 52-14430 (1977-02-01), None
patent: 52-24539 (1977-02-01), None
patent: 53-91752 (1978-08-01), None
patent: 54-4153 (1979-01-01), None
patent: 54-8542 (1979-01-01), None
patent: 54-68651 (1979-01-01), None
patent: 54-101334 (1979-08-01), None
patent: 54-118255 (1979-09-01), None
patent: 56-85702 (1981-07-01), None
patent: 58-10701 (1983-01-01), None
patent: 60-131503 (1985-07-01), None
patent: 64-50003 (1989-02-01), None
patent: 1-130106 (1989-05-01), None
patent: 1-222205 (1989-09-01), None
patent: 1-255803 (1989-10-01), None
patent: 4-31801 (1992-02-01), None
patent: WO 87/03676 (1987-06-01), None
McCallion et al., “Side-polished fiber provides functionality and transparency,” (Abstract) Laser Focus World, vol. 34, No. 9, p. S19-20, S22 S24, PennWell Publishing, Sep., 1998.
Das et al., “Automatic determination of the remaining cladding thickness of a single-mode fiber half-coupler,” (Abstract) Optics Letters, vol. 19, No. 6, p. 384-6, Mar. 15, 1994.
Ishikawa et al., “A new optical attenuator using the thermal diffusion of W-cladding fiber,” (Abstract) MOC/GRIN '97 Technical Digest of the 6thMicrooptics Conf./14thTopical Meeting on Gradient-Index Optical Systems in Tokyo, Japan, p. (vii+432+27), 208-11, Oct. 1997.
Matejec et al., “Optical fiber with novel geometry for evanescent-wave sensing,” (Abstract) Sensors and Actuators B, (Chemical), vol. B29, No. 1-3, p. 416-22, Elsevier Publishing, Oct. 1995.
Alonso et al., “Single-mode, optical-fiber sensors and tunable wavelength filters based on the resonant excitation of metal-clad modes,” (Abstract) Applied Optics, vol. 33, No. 22, p. 5197-201, Aug. 1, 1994.
Tomita et al., “Leaky-mode loss of the second propagating mode in single-mode fibres with index well profiles,” (Abstract) Applied Optics, vol. 24, No. 11, p. 1704-7, Jun. 1, 1995.
Leminger et al., “Determination of the variable core-to-surface spacing of single-mode fiber-coupler blocks,” (Abstract) Optics Letters, vol. 12, No. 3, p. 211-13, Mar. 1987.
Morshnev et al., “A fiber thermo-optical attenuator,” (Abstract) Source: Radiotekhnika i Elektronika, Translated in: Soviet Journal of Com
Pi Bo
Zhao Shulai
Doan Jennifer
Fish & Richardson P.C.
Oluma, Inc.
Uliah Akm E.
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