Dynamic gain equalization arrangement for optical signals

Patent 6892021 Issued on May 10, 2005. Estimated Expiration Date:

September 17, 2022. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

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Issued on: 09/03/2002
Inventor: Doerr

Inventor

Doerr, Christopher Richard

Assignee

Lucent Technologies Inc.

Application

No. 10245666 filed on 09/17/2002

US Classes:

385/140, Attenuator385/15, WITH OPTICAL COUPLER385/24Plural (e.g., data bus)

Examiners

Primary: Frech, Karl D.
Assistant: Hess, Daniel A.

Attorney, Agent or Firm

International Class

G02B006/12

Abstract

An optical dynamic gain equalization filter (DGEF) comprises a planar arrangement of preferably “perfectly sampled” (or alternatively oversampled) waveguide grating routers (WGR's) connected by individual optical paths each containing a Mach-Zehnder interferometer operated in a push-pull fashion so that a positive phase change in one interferometer arm and a corresponding negative phase change in the other interferometer arm produces a desired change in attenuation while, at the same time, the overall phase of the optical signals after passing through the Mach-Zehnder interferometer is kept constant with respect to the adjacent paths. Alternatively, the above-described arrangement is effectively “cut in half”, and its size effectively also reduced accordingly, using a mirror placed at the midpoint of the device and an appropriate circulator to separate the input and output optical signals.

Other References

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