Optical waveguides – Polarization without modulation
Patent
1991-11-08
1993-06-08
Lee, John D.
Optical waveguides
Polarization without modulation
385 7, G02B 614
Patent
active
052186539
ABSTRACT:
An apodized acousto-optic polarization converter in which two acoustic waveguides are (14, 20) are formed in a substrate and are separated by a small gap (18) such that the two acoustic waveguides act as a directional coupler in which acoustic power is transferred back and forth. An interdigitated transducer (12) launches a surface acoustic wave in the first acoustic waveguide, and an optical waveguide is formed in the middle of the second waveguide. An acoustic absorber (26) is formed over both acoustic waveguides at a distance from the transducer such that the acoustic wave is transferred from the first to the second waveguide and back again. Thereby, the optical signal in the optical waveguide is exposed to an acoustic power density that slowly increases to a maximum and then decreases with the result that the side lobes of the frequency spectrum for the converted signal are greatly reduced. The converter may be used as an electrically tunable optical filter using orthogonal input and output polarizers (30, 32).
REFERENCES:
patent: 4738501 (1988-04-01), Sunagawa et al.
patent: 5002349 (1991-03-01), Cheung et al.
G. R. Fowles (ed.), Introduction to Modern Optics, 2nd ed., Holt, Rinehart and Winston: 1975, pp. 138-139.
D. P. Morgan, "Surface-Wave Devices for Signal Processing," Elsevier: 1985, pp. 61-64.
R. C. Alferness, "Optical directional couplers with weighted coupling," Applied Physics Letters, 1979, vol. 35, pp. 261-262.
Y. Yamamoto et al., "Guided-Wave Acoustooptic Tunable Filters Using Simple Coupling Weighting Technique," Proceedings of 1990 IEEE Ultrasonics Symposium, 1990, pp. 605-608.
J. Frangen et al., "Integrated optical acoustically tunable wavelength filter," Electronics Letters, 1989, vol. 25, pp. 1583-1584.
E. Voges et al., "Integrated-Optic Devices on LiNbO.sub.3 for Optical Communication," Journal of Lightwave Technology, 1987, vol. Lt-5, pp. 1229-1237.
Johnson John J.
Smith David A.
Bell Communications Research Inc.
Guenzer Charles S.
Heartney Phan T.
Lee John D.
Suchyta Leonard Charles
LandOfFree
Polarization converter with apodized acoustic waveguide does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Polarization converter with apodized acoustic waveguide, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Polarization converter with apodized acoustic waveguide will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1947936