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:
Nov. 23, 1999
Filed:
May. 12, 1998
Douglas M Baney, Los Altos, CA (US);
Steven A Newton, Belmont, CA (US);
Wayne V Sorin, Mountain View, CA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
An optical switch includes a pump source, a pump director, and a pump-dependent attenuator. The pump-dependent attenuator passes optical signals when it is supplied with pump energy at a pumping wavelength and attenuates optical signals when it is not supplied with pump energy. The pump source generates pump energy for the pump-dependent attenuator, and the pump director optically manipulates the delivery of pump energy to the pump-dependent attenuator. In a preferred embodiment, the pump-dependent attenuator is an erbium-doped fiber (EDF), the pump source is a laser diode, and the pump director is a tunable fiber Bragg grating (FBG). The EDF is located along an optical signal transmission path between an input waveguide and an output waveguide. The tunable FBG is located along a transmission path between the laser diode and the EDF. To operate the switch, pump energy at a pumping wavelength is generated by the laser diode and transmitted toward the tunable FBG. To turn on the switch, the FBG is tuned off of the pumping wavelength of the EDF, thereby passing pump energy to the EDF, and to turn off the switch, the FBG is tuned onto the pumping wavelength of the EDF, thereby blocking pump energy to the EDF. An adjustable bandpass filter may also be used as the pump director. The optical switch can also be applied to various optical systems, such as a 1.times.N switch, add/drop multiplexers, broadcast/multicast switches, and wavelength-selectable lasers.