Ranjan Dutta

US Patent:

6344919, Feb 5, 2002

Filed:

May 5, 2000

Appl. No.:

09/565387

Inventors:

Ranjan Dutta - Lawrenceville NJ
William R. Holland - Warrington PA

Assignee:

Lucent Technologies, Inc. - Murray Hill NJ

International Classification:

G02F 2608

US Classification:

359301, 359110, 359246, 359251, 359298, 356 731, 356367, 356368

Abstract:

Methods and devices are provided for quickly producing all possible linear polarization states of light at the output of a length of optical fiber. Linearly polarized light is input and is transmitted through a fiber. Due to the birefringence of the fiber, light at the output of the fiber is elliptically polarized irrespective of the input polarization. The elliptically polarized states of light at the output are generated as an arbitrary circle on an output Poincare sphere. This arbitrary circle is then manipulated to produce a final circle substantially coinciding with the equator of the Poincare sphere. This final circle represents all possible linear polarization states at the output of the fiber. The invention eliminates the need for determining transformation matrices and performing point-by-point calculations in order to obtain input polarization settings for polarization-based, passive optical network (âPONâ) testing.

US Patent:

6748150, Jun 8, 2004

Filed:

Apr 30, 2003

Appl. No.:

10/426187

Inventors:

Ranjan Dutta - East Windsor NJ
Diego Fernando Grosz - Middletown NJ
Alejandra B. Gurevich - Maplewood NJ
Alain P. Kung - Fribourg, CH
Magaly Spector - Holmdel NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G02B 642

US Classification:

385123, 385 24, 385 31, 398 81, 398 82, 398 83, 398 85

Abstract:

The invention comprises a method and apparatus for implementing a relatively low cost add/drop multiplexer (OADM) wherein pre-demux and post-mux dispersion compensation is employed in a manner that substantially avoids imparting additional dispersion compensation to pass-through wavelength channels in a WDM system.

US Patent:

6911645, Jun 28, 2005

Filed:

Mar 7, 2003

Appl. No.:

10/383911

Inventors:

Alexander Beger - Bridgewater NJ, US
Ranjan Dutta - Lawrenceville NJ, US
Mitchell E. Haller - Marlboro NJ, US
Shuai Shen - East Brunswick NJ, US

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

G01J004/00

US Classification:

25022719, 250214 R

Abstract:

A channel detection system includes an interferometer coupled to a spectrum analyzer to differentiate additive spontaneous emission (ASE) noise from optical channels in a dense wave-division multiplex (DWDM) signal. It is assumed that channels, if present, are centered at frequencies corresponding to a standardized channel grid. The relative delay of the interferometer is chosen to be greater than the coherence time of the ASE noise but less than the coherence time of the channels with the interferometer's free spectral range set to an integer divisor of the channel-to-channel frequency spacing of the grid such that active channels experience a high degree of interference. The phase delay of the interferometer is then adjusted to maximize the interference at each grid-aligned frequency. The spectrum-analyzed outputs are compared (e. g. , subtracted from one another and then thresholded) to determine the channels present in the DWDM signal.

US Patent:

59030569, May 11, 1999

Filed:

Apr 21, 1997

Appl. No.:

8/845111

Inventors:

Everett Joseph Canning - Trenton NJ
Ranjan Dutta - East Windsor NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

H01L23/48

US Classification:

257773

Abstract:

The specification describes a thermocompression bonding process using anisotropic conductive film (ACF) bonding material in which the bonding pads are shaped to prevent depletion of conductive particles in the bonding region during compression. The process is useful in bump technology for interconnecting component assemblies on substrates such as glass, printed wiring boards, etc. The shaped structure can be made using photodefinable polymer strips around the bonding pads where the strips are thicker than the bonding pad. Alternative approaches to shaping one or both of the mating conductive surfaces are disclosed.

US Patent:

50757563, Dec 24, 1991

Filed:

Aug 31, 1990

Appl. No.:

7/576551

Inventors:

Ranjan Dutta - Lawrenceville NJ

Assignee:

AT&T Bell Laboratories - Murray Hill NJ

International Classification:

H01L 2348
H01L 2940
H01L 2144
H01L 2148

US Classification:

357 67

Abstract:

An ohmic contact to a III-V semiconductor material comprises substantially eighty to ninety-five percent by weight of tungsten, five to ten percent by weight of antimony, and zero to fifteen percent by weight of indium. The materials are simultaneously sputtered from separate targets in a sputtering reactor.

US Patent:

54157307, May 16, 1995

Filed:

Dec 14, 1993

Appl. No.:

8/167259

Inventors:

Everett J. Canning - Trenton NJ
Ranjan Dutta - Lawrenceville NJ

Assignee:

AT&T Corp. - Murray Hill NJ

International Classification:

H01L 21302

US Classification:

216 17

Abstract:

Aluminized optical fiber is used for transmitting electricity, as well as transmitting lightwaves. In one example, an aluminized optical fiber (17) is bonded within a photonics package in contact with a conductor (15) that interconnects it to a photonic device (12) or electronic circuit. Power is then supplied to the package by applying it to the aluminized coating (19) of the optical fiber. This avoids the need for a separate conductor extending into the photonics package for supplying electrical power. It also may significantly simplify system design since the power supply can conveniently be included a fairly remote distance from the photonics package. The aluminized optical fiber can be bonded to a metallization in the V-groove (13) that provides electrical contact simply by applying heat and pressure. This allows the aluminized fiber to be bonded without the need for any adhesives, while assuring good electrical contact for the transmission of electrical power. According to another embodiment (FIG.

US Patent:

50117920, Apr 30, 1991

Filed:

Feb 12, 1990

Appl. No.:

7/478875

Inventors:

Ranjan Dutta - Lawrenceville NJ

Assignee:

AT&T Bell Laboratories - Murray Hill NJ

International Classification:

H01L 21283

US Classification:

437184

Abstract:

An ohmic contact to III-V semiconductor material comprises substantially eighty to ninety-five percent by weight of tungsten, five to ten percent by weight of antimony, and zero to fifteen percent by weight of indium. The materials are simultaneously sputtered from separate targets in a sputtering reactor.

US Patent:

53891937, Feb 14, 1995

Filed:

Dec 14, 1993

Appl. No.:

8/167255

Inventors:

Alexander Coucoulas - Basking Ridge NJ
Ranjan Dutta - Lawrenceville NJ
Robert Klaiber - Lebanonon NJ

Assignee:

AT&T Corp. - Murray Hill NJ

International Classification:

H01L 21306
B44C 122

US Classification:

156633

Abstract:

Aluminized optical fiber (11) can be permanently bonded to silicon surfaces by applying both heat and pressure to the optical fiber. Thus, an optical fiber (11) can be bonded within a silicon V-groove (16) simply by applying heat and pressure, thereby to give an extremely accurate predetermined alignment of the central axis of the optical fiber within the V-groove, while avoiding the use of any potentially contaminating adhesives. This method can also be used to bond the aluminized fiber to aluminized V-grooves, as is described below.