Robert J Schroeder

US Patent:

6363180, Mar 26, 2002

Filed:

Apr 30, 1999

Appl. No.:

09/303163

Inventors:

Tsutomu Yamate - Brookfield CT
Robert J. Schroeder - Newtown CT
Rogerio T. Ramos - Bethel CT
Eric Udd - Troutdale OR

Assignee:

Schlumberger Technology Corporation - Ridgefield CT

International Classification:

G02B 600

US Classification:

385 12, 385 11, 385 37, 356 355, 356364

Abstract:

Methods for enhancing dynamic range, sensitivity, accuracy, and resolution in fiber optic sensors include manipulating the polarization characteristics of the light entering a fiber optic sensor and/or manipulating the polarization characteristics of the light exiting the sensor before it enters the light detection system. An apparatus according to the invention includes a fiber optic core having one or more gratings written onto it, a light source and a detection system for detecting light transmitted through the grating or reflected by the grating. The light source and the spectral demodulation system may be coupled to opposite ends of the fiber optic (transmission mode) or may be coupled to the same end of the fiber optic through the use of a beam splitter and terminators (reflection mode). Apparatus according to the invention include a polarizer and controller located either between the light source and the fiber or between the fiber and the detection system. Other embodiments of the invention include a depolarizing scrambler before the detection system so that the light entering the detection system is depolarized.

US Patent:

6751556, Jun 15, 2004

Filed:

Dec 12, 2002

Appl. No.:

10/317556

Inventors:

Robert J. Schroeder - Newtown CT
Jeffrey Tarvin - Brookfield CT
Rogerio T. Ramos - Chandlers Ford, GB
George A. Brown - Beaconsfield, GB

Assignee:

Sensor Highway Limited - Southampton

International Classification:

G01V 802

US Classification:

702 6, 702 12, 7315233

Abstract:

A technique usable with a subterranean well includes deploying a first optical sensor downhole in the subterranean well. The technique includes observing an intensity of backscattered light from the first optical sensor to measure a distribution of a characteristic along a portion of the well. The technique includes deploying a second sensor downhole to measure the characteristic at discreet points within the portion. The second sensor is separate from this first sensor and includes at least one interferometric sensor.

US Patent:

6946645, Sep 20, 2005

Filed:

Dec 11, 2003

Appl. No.:

10/733531

Inventors:

Jeffrey A. Tarvin - Brookfield CT, US
Robert J. Schroeder - Newtown CT, US
Rogerio T. Ramos - Chandlers Ford, GB
Tsutomu Yamate - Yokohama, JP

Assignee:

Schlumberger Technology Corporation - Ridgefield CT

International Classification:

G01B011/16

US Classification:

25022714, 25022718

Abstract:

High-resolution measurement of a parameter is provided at multiple different locations simultaneously along an optic fiber. Light within a predefined range of wavelengths is transmitted into an optic fiber that contains multiple birefringent fiber optic pressure transducers, each including a Fiber Bragg Grating. Each grating defines a spatially modulated index of refraction and a wavelength that is unique within the system. A sweeping comb filter is used to apply optical comb filtering to light reflected from the transducers so as to pass filtered light having multiple spectral portions, each spectral portion associated with one transducer. The free spectral range of the sweeping comb filter is set to be approximately equal to the spectral range of a single spectral portion. Wavelength division multiplexing is applied to the filtered light so as to separate the spectral portions. The value of a parameter is preferably determined using the spectral spacing of two maxima of spectral intensity in each spectral portion.

US Patent:

7126680, Oct 24, 2006

Filed:

May 18, 2006

Appl. No.:

11/436162

Inventors:

Tsutomu Yamate - Yokohama, JP
Robert J. Schroeder - Newtown CT, US
Rogerio T. Ramos - North Baddesley, GB
Oliver C. Mullins - Ridgefield CT, US

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

G01N 21/00

US Classification:

356 731

Abstract:

Methods for calibrating and making measurements using fiber optic sensors are disclosed using backscattered wavelengths and independent sensors. The disclosure sets outs methods applicable with fiber optic sensors either in a deployed in a loop and in a linear configuration and useful for measurements including temperature.

US Patent:

7215416, May 8, 2007

Filed:

Jun 12, 2006

Appl. No.:

11/450327

Inventors:

Tsutomu Yamate - Yokohama, JP
Robert J. Schroeder - Newtown CT, US
Rogerio T. Ramos - North Baddesley, GB
Oliver C. Mullins - Ridgefield CT, US

Assignee:

Schlumberger Technology Corp. - Sugar Land TX

International Classification:

G01N 21/00

US Classification:

356 731

Abstract:

Methods for calibrating and making measurements using fiber optic sensors are disclosed using backscattered wavelengths and independent sensors. The disclosure sets outs methods applicable with fiber optic sensors either in a deployed in a loop and in a linear configuration and useful for measurements including temperature.

US Patent:

7279678, Oct 9, 2007

Filed:

Aug 15, 2005

Appl. No.:

11/203743

Inventors:

A. Ballard Andrews - Wilton CT, US
Jacques Jundt - Bethel CT, US
Robert J. Schroeder - Newtown CT, US
Bhavani Raghuraman - Wilton CT, US
Oliver C. Mullins - Ridgefield CT, US

Assignee:

Schlumber Technology Corporation - Ridgefield CT

International Classification:

G01V 8/00

US Classification:

2502691

Abstract:

Methods and apparatus for analyzing a hydrocarbon mixture are disclosed, comprising at least one light-emitting diode (LED) and at least one photodetector positioned to detect energy transmitted by the LED through a sample of the hydrocarbon mixture. In at least one embodiment an optical filter is coupled to the output of the LED to mitigate the adverse effects of the LED's sensitivity to temperature.

US Patent:

8389054, Mar 5, 2013

Filed:

Aug 14, 2008

Appl. No.:

12/191908

Inventors:

Dan Eugen Angelescu - Noisy le Grand Cedex, FR
Robert J. Schroeder - Newtown CT, US

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

C23C 16/00

US Classification:

427250

Abstract:

Methods and related systems for fabricating a device or a part, the method including the step of growing at least one material from a vapor phase, by a CVD process, for example a MO-CVD process, on a heated base substrate, wherein the at least one material conforms to one of at least one topographical pattern of the base substrate, one or more predefined geometrical shape on the base substrate or both. The method includes removing the base substrate embedded in the CVD deposited material, as well as optionally machining a portion of the CVD deposited material.

US Patent:

8564768, Oct 22, 2013

Filed:

Dec 18, 2009

Appl. No.:

12/642385

Inventors:

Robert Schroeder - Newtown CT, US
Bill Grant - Cedar Creek TX, US
Dan Angelescu - Noisy le Grand Cedex, FR

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

G01N 1/10

US Classification:

356246, 250258

Abstract:

Devices, methods and systems for making optical measurements of a fluid at elevated pressures and temperatures are disclosed. A cell is designed for the optical spectroscopic measurements of fluids or gas using light from ultra violet (UV) to far infrared wavelengths, among other wavelengths. A cell is described that is well suited for applications using very small fluid volumes, on the order of micro liters, such as microfluidic systems. Some described embodiments are suited for very high pressure and temperature environments (for example, 20 kpsi or greater at 175 degree C. or greater). Such conditions, for example, may be found in oilfield downhole environments. Some embodiments provide are inexpensive, and make use of replaceable lenses that are used as a pressure barrier and for collimation of the optical beam path for spectroscopic measurements.