Optical waveguides – With optical coupler – Particular coupling structure
Patent
1997-04-30
1998-12-01
Lee, John D.
Optical waveguides
With optical coupler
Particular coupling structure
252582, 385146, 4284735, B32B 2700, G02B 626
Patent
active
058450254
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
This invention relates to novel optical devices and, more particularly, to high speed, high bandwidth integrated polymer electro-optic modulators.
BACKGROUND OF THE INVENTION
Electro-optic (EO) modulators have been identified as likely alternatives to diode direct modulators for the next generation of single-mode transmission systems (see, e.g., Korotoky, et al., J. Lightwave Technol., 1985, LT-3, 1027.) Among external modulators, poled polymer EO modulators have demonstrated particular potential for such applications. (see, e.g., Teng, Appl. Phys. Lett. 1992, 60(13), 1538.) Poled polymer modulators provide many attractive characteristics and advantages, including large optical nonresonant EO coefficients, low dielectric constants, ultrafast electronic responses, multiple layer device ability, and simple fabrication techniques which are compatible with standard semiconductor device manufacturing steps. By comparison with Ti:LiNbO.sub.3 EO modulators and semiconductor EO modulators, poled polymer EO modulators are easier to fabricate.
Important properties for evaluating EO modulators include coupling strength, bandwidth, insertion loss, voltage-length-product, and driving power. Although a number of EO modulators have been reported, such devices have not yet met industry performance criteria. Indeed, most known EO modulators exhibit only weak coupling, narrow bandwidth, high insertion loss, high voltage-length product, and/or high driving power. Thus, there remains a need in the art for improved devices that meet industry standards.
OBJECTS OF THE INVENTION
It is one object of the present invention to provide optical (e.g., electro-optical) devices.
It is another object of the invention to provide EO modulators, particularly those that exhibit tunable strong coupling.
It is yet another object to provide poled polymer EO devices.
It is yet another object to provide methods for designing and fabricating optical devices.
It is still another object to provide methods for operating the optical devices of the present invention.
SUMMARY OF THE INVENTION
These and other objects are satisfied by the present invention, which provides a new class of optical devices wherein optical waveguide elements are coupled by introducing an optical coupling element between them to permit strong optical coupling between the waveguides in a direction generally perpendicular to the direction in which light would propagate in the waveguide in the absence of the coupling element.
The optical devices of the invention generally include first and second waveguide members that each have a longitudinal surface extending between a light input surface and a light output surface. Disposed between the first and second members and optically coupled to each is an optical coupling member that can be used to tune the coupling strength between the first member and second member. Surrounding the members is some form of cladding. In preferred embodiments, the longitudinal surface of the first member includes a first coupling surface, the longitudinal surface of the second member includes a second coupling surface, and the coupling member includes surfaces that are coupled, respectively, with the first coupling surface and the second coupling surface.
The first member, second member, and coupling member can be fabricated from a variety of materials and in a variety of dimensions and shapes. The first member and the second member preferably have similar shape and dimensions and the coupling member preferably has shape and dimensions that are different from the first and second members, and a refractive index that is larger than the refractive index of the first and second members or the cladding. In preferred embodiments, devices of the invention further include means for applying light to one or both input surfaces, electrode means for establishing a modulating electric field within the device, and output means for receiving light discharged from one or more of the output surfaces.
In contrast to traditional directiona
REFERENCES:
patent: 4026632 (1977-05-01), Hill et al.
patent: 4400053 (1983-08-01), Kazkaz
patent: 4431263 (1984-02-01), Garito
patent: 4439514 (1984-03-01), Garito
patent: 4483583 (1984-11-01), Unger
patent: 4536450 (1985-08-01), Garito
patent: 4581315 (1986-04-01), Garito
patent: 4615962 (1986-10-01), Garito
patent: 4759596 (1988-07-01), Po et al.
patent: 4950044 (1990-08-01), Makita
patent: 5071997 (1991-12-01), Harris
Garito, A.F., et al., "Origin of Nonlinear Optical Properties of Rigid Rod Polymers", MRS Int'l. Mtg. On Adv. Mats., 12, 1989, Materials Research Society, pp. 3-20.
Garito, A.F., et al., "Microscopic Origin of Second Order Nonlinear Optical Properties of Organic Structures" Edited by Paras N. Parsad and Donald R. Ulrich (Plenum Publishing Corp., 1988).
Garito, A.F. and Singer, K., "Organic Crystals and Polymers--A New Class of Nonlinear Optical Materials", Reprinted from Laser Focus Magazine, Feb., 1982, pp. 59-64.
Heflin, J.R. and Garito,A.F., "Optics Beyond the Limits", Nature, 356, Mar. 19, 1992.
Lindle, J.R., et al., "Nonlinear Optical Properties of Benzimidazobenzophenanthroline Type Ladder Polymers", Applied Physics Letters, 1990, 56(8), 712-714.
Sroog, C.E., "Polymides", Prog. Polym. Sci., 1992, 16, 561-694.
Teng, C.C. and Garito, A.F., "Dispersion of the Nonlinear Second-Order Optical Susceptibility of an Organic System: p-Nitroaniline", The American Physical Society, 1983, 50, 350-352.
Ermer, et al., "Thermally Stable Electrooptic Polymers", Polymer Preprints, 1991, 32(3), 92-93.
Wu, et al., "Highly Thermally Stable Electrooptic Response in Poled Guest-Host Polyimide Systems Cured at 360.degree. C.", J. Applied Phys., Oct. 1991, 69, 7366-7368.
Cai Yongming
Garito Anthony F.
Qian Qiuming
Lee John D.
The Trustees of the University of Pennsylvania
LandOfFree
Optical coupling device and process for modulating light does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Optical coupling device and process for modulating light, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical coupling device and process for modulating light will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2401706