Texas Instruments Corporation

Jds Uniphase Corporation

Lumentum Operations LLC

Leonid Frenkel

Barthelemy Fondeur

Jinxi Shen

David R Walker

Yimin Hua

Vlatko Milinkovic

Yu Zhang

Andrew Gerrit Huibers

Satyadev R Patel

Peter W Richards

Regis Grasser

Jim Dunphy

Igor Volfman

Greg Schaadt

A tunable PLC optical filter having sequentially connected thermally tunable Mach-Zehnder (MZ) interferometers is described. The cascade of MZ interferometers, each having a free spectral ranges matching ITU frequency grid spacing, are tuned so as to have a common passband centered on the frequency of the signal being selected, while having at least one of the stopbands centered on any other ITU frequency. Any other optical channel that may be present at any other ITU frequency is suppressed as a result. Another MZ interferometer in series with the cascade of interferometers including an asymmetric or variable coupler, is tuned to have low transmission at the center frequency of the selected optical channel.

Flat-top tunable filter

A tunable optical filter is configured to take point measurements at a few optical frequencies per frequency channel of a DWDM optical network. The measurement frequencies are shifted by pre-determined amounts relative to the optical frequency channel being characterized. Since the spectral shape of the tunable optical filter is known, the center optical frequency, the modulation bandwidth, and the total optical power of the channel can be obtained from as few as three optical measurements. The center optical frequency and the total optical power can be continuously monitored by providing a tunable filter stage coupled to an interleaver stage, and computing a ratio and a weighted sum the optical signals at the two outputs of the interleaver stage.

Characterizing a frequency channel in an optical network

The invention provides a method and apparatus for evaluating the product quality and performances of micromirror array devices through measurements of the electromechanical responses of the individual micromirrors to the driving forces of electric fields. The electromechanical responses of the micromirrors according to the present invention are described in terms of the rotational angles associated with the operational states, such as the ON and OFF state angles of the ON and OFF state when the micromirror array device is operated in the binary-state mode, and the response speed (i.e. the time interval required for a micromirror device to transit form one state to another) of the individual micromirrors to the driving fields.

Performance analyses of micromirror devices

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Palo Alto, CA, United States of America

Leonid Frenkel