The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 08, 1993
Filed:
Nov. 08, 1991
John J Johnson, Middletown, NJ (US);
David A Smith, Freehold, NJ (US);
Bell Communications Research, Inc., Livingston, NJ (US);
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).