Optical waveguides – With optical coupler – Particular coupling function
Reexamination Certificate
2001-09-26
2003-07-22
Ullah, Akm E. (Department: 2874)
Optical waveguides
With optical coupler
Particular coupling function
C385S024000, C385S028000, C385S031000, C385S032000, C385S039000
Reexamination Certificate
active
06597833
ABSTRACT:
BACKGROUND
This application relates to optical signal multiplexers, and in particular, to optical signal multiplexers and demultiplexers based on evanescent coupling through a polished fiber coupling port.
Optical waves may be transported through optical waveguiding elements or “light pipes” such as optical fibers, or optical waveguides formed on substrates. 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 waveguides formed on substrates can also be designed to provide spatial optical confinement based on total the internal reflection. Planar waveguides, for example, may be formed by surrounding a slab or strip of a dielectric material with one or more dielectric materials with refractive indices less than that of the dielectric slab or strip.
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. Optical waveguides on substrates may be used in integrated optical devices where optical elements, opto-electronic elements, or MEMS elements are integrated on one or more substrates.
The guided optical energy in the fiber or waveguide, however, is not completely confined within the core of the fiber or waveguide. In a fiber, for example, 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
This application includes optical devices having at least one fiber integrated on or engaged to a substrate fabricated with one or more grooves. One portion of the cladding of this fiber is removed and polished to form a fiber coupling port through which optical energy can be evanescently coupled into or out of the fiber core via evanescent fields. At least two such fiber coupling ports may be formed at different positions in the fiber such that this fiber can be coupled with two coupling ports of another fiber or planar waveguide to form a Mach-Zehnder interferometer for signal processing operations such as optical attenuation, optical modulation, optical switching, and signal multiplexing or demultiplexing.
The fiber may be mounted and engaged to one or more grooves formed in a substrate in a fiber device. One embodiment includes a substrate that is formed with an elongated groove on one substrate surface, and at least one opening located at one end of the groove that penetrates through the substrate. An optical fiber is engaged to the substrate by passing through the opening to lay a portion in the groove. The fiber cladding of the portion in the groove may be partially removed to form a fiber coupling port to allow for evanescent coupling.
The optical coupling between a fiber in a first substrate in one of the above fiber devices and a waveguide formed in a second substrate may be implemented by positioning the first and the second substrates relative to each other so that a coupling port of the fiber is adjacent to the waveguide to allow for evanescent coupling between the fiber and the waveguide. A single fiber may be optically coupled to two or more waveguides through its different coupling ports located in grooves of the first substrate.
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: 6031948 (2000-02-01), Chen
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: 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
T. Ono and Y. Yano; Key technologies for terabit/second WDM systems with high spectral efficiency of over 1 bit/s/Hz; IEEE Journal of Quantum Electronics, vol. 34, No. 11, Nov. 1998.
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-cla
Pi Bo
Zhao Shulai
Doan Jennifer
Fish & Richardson P.C.
Oluma, Inc.
Ullah Akm E.
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