Edward M Laskowski

US Patent:

6925232, Aug 2, 2005

Filed:

May 30, 2003

Appl. No.:

10/448711

Inventors:

Edward John Laskowski - Short Hills NJ, US
Christi Kay Madsen - South Plainfield NJ, US
Annjoe Golangco Wong-Foy - Basking Ridge NJ, US

Assignee:

Lucent Technologies, Inc. - Murray Hill NJ

International Classification:

G02B006/26
G02B006/10

US Classification:

385 39, 385129

Abstract:

In accordance with the invention, a high speed thermo-optic phase shifter comprises a length of optical waveguide including a waveguiding core of a first material having an index of refraction nand a first order temperature dependence |dn/dT| and, optically coupled to the core, a length of a second material having an index npreferably greater than the core (n>n) and a first order temperature dependence |dn/dT| than the core (|dn/dT|>|dn/dT|). Advantageously, the length of second material is adiabatically tapered at both ends. Upon heating, as by a resistance heater, the second material changes the optical pathlength by an amount predominantly determined by |dn/dT| providing faster switching speed. In a preferred embodiment, the core comprises silica, and the second material comprises silicon to produce switching speeds up to a few hundred MHz.

US Patent:

54061946, Apr 11, 1995

Filed:

Sep 21, 1992

Appl. No.:

7/948059

Inventors:

Douglas R. Dykaar - Gillette NJ
Ulrich D. Keil - Warren NJ
Rose F. Kopf - Greenbrook NJ
Edward J. Laskowski - Scotch Plains NJ
George J. Zydzik - Columbia NJ

Assignee:

AT&T Corp. - Murray Hill NJ

International Classification:

G01R 3100

US Classification:

324 96

Abstract:

A new electro-optic sampling probe with femtosecond resolution suitable for ultra-fast electro-optic sampling. The new probe is several times thinner and has a dielectric constant four times less than the best reported conventional bulk LiTaO. sub. 3 probes. In addition, the ultimate bandwidth is 50 percent greater than an equivalent LiTaO. sub. 3 probe. The probe is a thin film of Al. sub. x Ga. sub. 1-x As used in both total internally reflecting and free-standing geometries. Here x is chosen for sufficient transmission of the crystal to the wavelength of the laser source being used for electro-optic sampling. The thickness of the film is a small fraction of the thickness of prior art probes and is chosen, for speed and sensitivity of electro-optic sampling, to be thin compared to the spatial extent of the laser pulse. The thin film probe eliminates many of the problems associated with the use of bulk crystals as electro-optic sensors.

US Patent:

55966616, Jan 21, 1997

Filed:

Dec 28, 1994

Appl. No.:

8/365618

Inventors:

Charles H. Henry - Skillman NJ
Edward J. Laskowski - Scotch Plains NJ
Yuan P. Li - Alpharetta GA
Cecilia Y. Mak - Bedminster NJ
Henry H. Yaffe - Dunwoody GA

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

C02B 628

US Classification:

385 24

Abstract:

In accordance with the invention, a new type of monolithic optical waveguide filter comprises a chain of optical couplers of different effective lengths linked by differential delays of different lengths. The transfer of the chain of couplers and delays is the sum of contributions from all possible optical paths, each contribution forming a term in a Fourier series whose sum forms the optical output. A desired frequency response is obtained by optimizing the lengths of the couplers and the delay paths so that the Fourier series best approximates the desired response. The filter is advantageously optimized so that it is insensitive to uncontrolled fabrication errors and is short in length. The wavelength dependence of practical waveguide properties is advantageously incorporated in the optimization. Consequently, the filter is highly manufacturable by mass production.

US Patent:

61155209, Sep 5, 2000

Filed:

Mar 5, 1998

Appl. No.:

9/035317

Inventors:

Edward John Laskowski - Scotch Plains NJ
Dirk Joachim Muehlner - Berkely Heights NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G02B 626
G01B 902

US Classification:

385 50

Abstract:

The present invention includes a MZI comprising a pair of folded waveguides disposed between a pair of couplers. Each folded waveguide comprises a pair of segments intersecting at a reflector. The respective reflectors are different distances from the couplers to provide a major portion of the differential path length between the two arms. In a preferred embodiment, the reflectors are polysilicon mirrors and can be formed by etching through the intersecting waveguides and depositing polysilicon. The result is a compact MZI that can be used as a multiwavelength reference for a laser light source on a common silicon optical bench chip.

US Patent:

57199760, Feb 17, 1998

Filed:

Oct 24, 1995

Appl. No.:

8/547767

Inventors:

Charles Howard Henry - Skillman NJ
Edward John Laskowski - Scotch Plains NJ
Yuan P. Li - Duluth GA
Henry Howard Yaffe - Dunwoody GA

Assignee:

Lucent Technologies, Inc. - Murray Hill NJ

International Classification:

G02B 626

US Classification:

385 50

Abstract:

An optimized waveguide structure enables the functional integration of various passive optic components on a single substrate. The optimized waveguide structure is characterized by a thicker core layer than used for square core waveguides and a core width that changes according to different functional regions of the optic circuit within which it is incorporated. The height (H) of the waveguide core is determined by the thickness of the core layer defined during the fabrication process and is ideally uniform across the circuit. The width (W) of the core, however, is changed between functional regions by the photo-lithographic mask and the chemical etching during the fabrication process. By way of example, an optimized waveguide structure for a P-doped silica planar waveguide with a. DELTA. approximately 0.

US Patent:

56299990, May 13, 1997

Filed:

Mar 10, 1995

Appl. No.:

8/401545

Inventors:

Charles H. Henry - Skillman NJ
Edward J. Laskowski - Scotch Plains NJ
Yuan P. Li - Scotch Plains NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G02B 626

US Classification:

385 43

Abstract:

The present invention relates to a waveguide taper. The waveguide taper has a first end and a second end for being coupled with a fiber. The core has an overall width that progressively increases from the waveguide end toward the fiber end such that the width of the fiber end of the taper corresponds to the diameter of the core of the fiber. Side-gaps are disposed in the sides of the core and extend into the core but not across the entire width of the core. The depth of the side-gaps progressively increases from the waveguide end to the fiber end of the taper. In one embodiment, the side-gaps may be aperiodically and/or randomly disposed along the length of the taper and the side-gaps can be disposed at different angles to a direction of light propagation along a length of the core.

US Patent:

60028238, Dec 14, 1999

Filed:

Aug 5, 1998

Appl. No.:

9/129522

Inventors:

Edwin Arthur Chandross - Murray Hill NJ
Arturo Hale - New York NY
Valerie Jeanne Kuck - Upper Montclair NJ
Edward John Laskowski - Scotch Plains NJ
Christi Kay Madsen - South Plainfield NJ
Ronald Edward Scotti - White House Station NJ
Joseph Shmulovich - Murray Hill NJ

Assignee:

Lucent Techolonogies Inc. - Murray Hill NJ

International Classification:

G02B 626

US Classification:

385 50

Abstract:

The thermo-optically controlled optical couplers wherein the coupling region between the waveguides in the coupling section is filled with a material having a high dependence of refractive index on temperature thus making the thermo-optic control means more efficient and allowing a greater range of adjustment in the coupling coefficient for a given temperature change.

US Patent:

55771416, Nov 19, 1996

Filed:

Mar 10, 1995

Appl. No.:

8/402266

Inventors:

Renen Adar - Haifa, IL
Edward J. Laskowski - Scotch Plains NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G02B 600
G02B 636

US Classification:

385 43

Abstract:

The invention relates to a fixed gap waveguide taper. The waveguide taper has a first end and a second end for being coupled to a fiber. The waveguide taper includes a plurality of segments extending from the first end toward the second end. The segments include a gap portion and a core portion. In the present invention, the gap portion remains fixed at a constant length s throughout the entire waveguide taper. In contrast, the core section of the segment varies from the waveguide end of the taper toward the fiber end of the taper. In particular, the core section in each of the segments progressively decreases in length from the waveguide end toward the fiber end of the taper. Accordingly, the length of the segment. LAMBDA. progressively decreases from the waveguide end toward the fiber end of the taper.