Christopher M Doerr

US Patent:

6351581, Feb 26, 2002

Filed:

Mar 17, 1998

Appl. No.:

09/040477

Inventors:

Christopher Richard Doerr - Middletown NJ
Yuan P. Li - Duluth GA

Assignee:

Agere Systems Optoelectronics Guardian Corp. - Orlando FL

International Classification:

G02B 626

US Classification:

385 24, 359124

Abstract:

An optical add-drop multiplexer (ADM) avoids waveguide crossings by being constructed in the form of a Mach-Zehnder interferometer having a demultiplexer/multiplexer (demux/mux) pair in each of its arms. Each demux/mux pair is interconnected by coherent connecting paths having heating elements for increasing the path length of selected connecting paths. Waveguide optical couplers having asymmetric transfer functions are used at the input and output of the ADM. These couplers cooperate with the activated heating elements to add and/or delete a selected optical channel to/from an optical transmission path. Each coherent connecting path includes a number of waveguides. The end-to-end transmission characteristic of the ADM through each individual waveguide has a Gaussian shape. These Gaussian shapes are designed intersect at their -3 dB wavelengths so that the end-to-end transmission characteristic of the ADM is flat.

US Patent:

6385373, May 7, 2002

Filed:

Jan 25, 2000

Appl. No.:

09/490610

Inventors:

Christopher Richard Doerr - Middletown NJ
Corrado Pietro Dragone - Little Silver NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G02B 626

US Classification:

385 46, 385 33, 385 37, 385 50, 359130, 359131

Abstract:

When two star couplers are cascaded so as to perform two Fourier transformations without phase distortions, an imaging arrangement results which accurately reproduces at the output the input distribution. In order to achieve high efficiency of power transfer between a relatively large number of input ports and a relatively large number of output ports and a small star-coupler physical size, the input and output waveguides connected to the star coupler must be relatively narrow and be closely spaced at the star coupler. However close spacing gives rise to significant mutual coupling between adjacent waveguides, leading to undesirable crosstalk between the channels of the device. We have discovered that the phase distortion is approximately periodic and may be compensated for by adding or subtracting length to the waveguides between the star couplers. The path length correction is essentially a sinusoid with the minimum increase in required path length being applicable to the ports at the centers of the star-coupler Brillouin zones and the maximum increase in required length being applicable to the ports at the edges of the star-coupler Brillouin zones.

US Patent:

6393173, May 21, 2002

Filed:

Mar 28, 2000

Appl. No.:

09/535785

Inventors:

Christopher Richard Doerr - Middletown NJ
Pierre Schiffer - Delft, NL

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G02B 635

US Classification:

385 16, 385 24, 385 18

Abstract:

An optical circulator is connected to each end of an integrated circuit chip containing a pair of multiplexer/demuliplexers driving respective arrays of 2Ã2 MZIs separated by a striped mirror interface and a plate having a thickness of  the central wavelength on each side of the mirror. Light passes through the device twice making it polarization insensitive in power and in wavelength. Phase errors due to inserting these plates will not cause power disturbances because no interference exists. Because the same router is used for multiplexing/demultiplexing, there are no loss/crosstalk penalties for through-channels due to mismatch in wavelength response. Back reflections for the switch-conditions are suppressed by aligning the waveguide, which passes the striped mirror, under a slight angle so that reflected light at the interface will penetrate the substrate. Lateral offset applied between the ends of two waveguides at the mirror interface ensures that crosstalk performance is not limited.

US Patent:

6408111, Jun 18, 2002

Filed:

Apr 4, 2000

Appl. No.:

09/542426

Inventors:

Christopher Richard Doerr - Middletown NJ
Lawrence Warren Stulz - Neptune NJ

Assignee:

Agere Systems Guardian Corp. - Orlando FL

International Classification:

G02F 1035

US Classification:

385 3, 385 14, 385132

Abstract:

A planar lightguide circuit (PLC) phase shifter is fabricated on a chip which exhibits reduced thermal crosstalk by reducing the thermal resistance between the waveguide cores and the thermal âgroundâ (e. g. , a heat sink) compared to the thermal resistance between the waveguide cores. This is accomplished by removing some of the glass from the backside of the chip over a small area under the phase shifters, depositing metal on the backside, and soldering it to a copper block heat sink.

US Patent:

6504970, Jan 7, 2003

Filed:

Mar 15, 2001

Appl. No.:

09/809124

Inventors:

Christopher Richard Doerr - Middletown NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G02B 628

US Classification:

385 24, 385 46, 359124

Abstract:

A method and apparatus are disclosed for filtering an input wavelength-division multiplexed (WDM) signal comprised of N wavelength channels. The disclosed wavelength blocker includes a demultiplexer for producing a plurality of demultiplexed output signals from the input WDM signal and a multiplexer for producing an output WDM signal. A shutter array selectively passes each of the N wavelength channels using a plurality of shutters. The demultiplexer is coupled to the multiplexer using a plurality of waveguides having approximately equal length, in order to reduce multipath interference. Each of the N wavelength channels are selectively passed or blocked using a thermo-optic or electro-optic control signal to control the state of the corresponding shutter. Crosstalk can be reduced using dilation techniques that position two shutters in series, especially where the shutters are thermo-optic Mach-Zehnder switches. Wavelength-selective cross connects and wavelength add-drop multiplexers are also disclosed that employ the novel wavelength blockers.

US Patent:

6519059, Feb 11, 2003

Filed:

Sep 30, 1999

Appl. No.:

09/408932

Inventors:

Christopher Richard Doerr - Middletown NJ
Randy Clinton Giles - Whippany NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

H04J 1402

US Classification:

359124, 359127, 359128, 359114

Abstract:

An arrangement is disclosed for providing optical wavelength adding/dropping. The arrangement includes two duplicated-port waveguide grating routers (WGR) and a plurality of attenuator-switches. The first WGR is configured as a 1Ã2N demultiplexer and the other as a 2NÃ1 multiplexer. Each WGR includes a duplicated plurality of input or output waveguides, wherein respective pairs of each plurality have substantially identical spectral characteristics. The first plurality of output waveguides of the first WGR is coupled to the first plurality of input waveguides of the second WGR. Attenuator-switches are inserted between these two pluralities of waveguides that can be used to block incident optical wavelengths corresponding to channels to be terminated at the node where the arrangement is provided. The second plurality of output waveguides in the first WGR are drop waveguides where dropped channels exist. The second plurality of input waveguides in the second WGR are add waveguides to provide full add/drop capability.

US Patent:

6556736, Apr 29, 2003

Filed:

Jul 17, 2001

Appl. No.:

09/906965

Inventors:

Christopher Richard Doerr - Middletown NJ
Hyang Kyun Kim - Sunnyvale CA

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G02F 101

US Classification:

385 14, 385 1, 385 2, 385 3, 385140, 359127, 359130

Abstract:

The curvature, tilt, and attenuation of the passband of an optical signal is dynamically controlled by an integrated compensator that is advantageously electrically operated. The compensator arrangement can be replicated, and used to independently and dynamically control the passbands of multiple optical signals having different wavelengths, for example in a multiplexing and/or demultiplexing arrangement. Each compensator includes a â50/50â splitter arranged to divide an optical signal into first and second copies. One copy is applied to a first variable optical attenuator (VOA) via a tunable phase shifter, while the other copy is applied to a second VOA directly. The outputs of the first and second VOAs are then combined, for example in a planar waveguide grating. In the output on the other side of the grating, the two copies interfere. When the copy phase shift is zero, the net passband is Gaussian; when the copy phase shift magnitude is /2, the net passband is flat; and when the copy phase shift magnitude is between /2 and , the net passband has a dip in the middle.

US Patent:

6658174, Dec 2, 2003

Filed:

Mar 16, 2001

Appl. No.:

09/810135

Inventors:

Christopher Richard Doerr - Middletown NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G02B 628

US Classification:

385 16, 385 24, 385 39, 385140

Abstract:

A thermo-optic interferometer switch is arranged to operate in a Push-pull mode by placing approximately a quarter-wavelength effective path-length difference (90 degree bias) between the arms of an interferometer switch in the zero-drive state, and then driving one arm to activate the switch to one state (e. g. , the bar state), and driving the other arm to go to the other state (e. g. the cross state).