Optical waveguides – Integrated optical circuit
Reexamination Certificate
2001-12-05
2003-11-04
Palmer, Phan T. H. (Department: 2874)
Optical waveguides
Integrated optical circuit
C385S132000, C385S008000, C385S145000, C385S126000
Reexamination Certificate
active
06643419
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to fiber optic devices used for communication and other applications. More specifically, the present invention relates to planar lightwave circuits.
2. Description of the Related Art
As is well-known in the art, many optical circuits use optical guides: planar lightwave circuits constructed with patterned silicon-dioxide layers on a silicon substrate.
Planar lightwave circuits (PLCs) made of low-loss silica promise to make significant impact as they reach commercial viability. Indeed, silica-based planar lightwave circuits—passive optical waveguide structures made using photolithographic techniques—comprise one of the most dynamic segments of the photonics field. Among their key virtues are extremely low propagation loss (0.01 dB/cm), excellent fiber coupling loss (0.1 dB for low index contrast waveguides), ease of defining complex structures such as Arrayed Waveguide Grating (AWGs) and Mach-Zehnder arrays using photolithographic fabrication processes, mode compatibility with optical fibers, and physical robustness. However, silica is a passive material with no electrically controlled phase shifting ability except for slow thermo-optic index modulation techniques.
In general, passive materials, previously used for routing and switching, offer low losses but suffer from low speeds and are not electrically responsive. Active materials, used for modulators and other devices, offer higher speeds but suffer from higher losses as well.
Consequently, a need exists in the art for a system and method for integrating low loss passive materials with active high speed electro-optic materials to make more sophisticated devices such as modulators, routers, and switches using fabrication processes compatible with both passive and active materials.
SUMMARY OF THE INVENTION
The need the art is addressed by the device for effecting a transition from a passive waveguide to an active waveguide or from an active waveguide to a passive waveguide of the present invention. The inventive device comprises a first cladding; a first core disposed within the first cladding; and a ground plane disposed over the first cladding and the core. A second cladding is disposed on the ground plane. A second core is disposed on the second cladding. A third cladding is disposed on the second cladding and the second core and an electrode is disposed on top of the third cladding.
The inventive device enables the construction of a novel and advantageous switch comprising an input port; an output port; and plural waveguides disposed between the input port and the output port. Each waveguide includes a first cladding; a first core disposed within the first cladding; and a ground plane disposed over the first cladding and the core. A second cladding is disposed on the ground plane. A second core is disposed on the second cladding. A third cladding is disposed on the second cladding and the second core and an electrode is disposed on top of the third cladding.
The inventive device also enables a unique and advantageous router design comprising an active tuned arrayed waveguide grating and switching logic, for controlling the grating. In the illustrative embodiment, the grating includes an input port; an output port; and plural waveguides disposed between the input port and the output port. Each waveguide includes a first cladding; a first core disposed within the first cladding; and a ground plane disposed over the first cladding and the core. A second cladding is disposed on the ground plane. A second core is disposed on the second cladding. A third cladding is disposed on the second cladding and the second core and an electrode is disposed on top of the third cladding.
REFERENCES:
patent: 4781424 (1988-11-01), Kawachi et al.
patent: 6229949 (2001-05-01), Ido et al.
patent: 6421161 (2002-07-01), Rice
K. Kato and Y. Tohmori, “PLC hybrid integration technology and its application to photonic components,”IEEE Journal of Selected Topics in Quantum Electronics, vol 6, No. 1, Jan./Feb. 2000.
L. Ketelsen et al., “Electro-absorption modulated 1.55um wavelength selective DFB array using hybrid integration,” Proceedings of OFC'99, 1999, paper PD4-1.
S. Garner et. al, “Three dimensional integrated optics using polymers,” IEEE Journal of Quantum Electronics, vol. 35, No. 8, Aug. 1999.
N. Keil et al., “Thermal-optic vertical coupler switches using hybrid polymer/silica integration technology,” Electronics Letters, vol. 36, No. 5, Mar. 2000.
Bachmann M., Besse P., Melchior H., “General self-imaging properties in NxN multimode interference couplers including phase relations.” Applied Optics, vol 33, No. 18, pp 3905-3911, 1994.
Ferreras A. et. al., “Useful formulas for multimode interference power splitter/combiner design.” IEEE Photonics Technology Letters, vol. 5, No. 10, pp 1224-1227, 1993.
Jenkins et. al., “Novel 1xN and NxN integrated optical switches using self-imaging multimode GaAs/AlGaAs waveguides.” Applied Physics Letters, vol. 64, No. 6, pp 684-686, 1993.
Smit, M. and van Dam, C, PHASAR-Based WDM Devices:Principles, Design, and Applications. IEEE Journal of Selected Topics in Quantum Electronics, vol. 2, No. 2, pp236-250, 1996.
Azfar Talal
Chang Daniel H.
Fetterman Harold R.
Michael Joseph
Benman, Brown & Williams
Pacific Wave Industries, Inc.
Palmer Phan T. H.
LandOfFree
Ultra-high speed, active polymer-silica hybrid, single... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Ultra-high speed, active polymer-silica hybrid, single..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ultra-high speed, active polymer-silica hybrid, single... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3160642