Kenneth J Stephenson

US Patent:

7960687, Jun 14, 2011

Filed:

Sep 30, 2010

Appl. No.:

12/895463

Inventors:

Matthieu Simon - Princeton NJ, US
Kenneth Stephenson - Princeton NJ, US

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

G01V 5/08

US Classification:

2502691

Abstract:

Systems, methods, and devices relating to a sourceless X-ray downhole tool are provided. By way of example, such a downhole tool may include an X-ray generator, an X-ray detector, and data processing circuitry. The X-ray generator may emit some X-rays out of the downhole tool and some X-rays internally through the downhole tool. The X-ray detector may detect some of the X-rays that return to the downhole tool, as well as some of the X-rays that pass internally through the downhole tool. The data processing circuitry may gain-stabilize the X-ray detector based at least in part on the X-rays that passed internally through the downhole tool and were detected by the X-ray detector.

US Patent:

20110180698, Jul 28, 2011

Filed:

Feb 26, 2009

Appl. No.:

12/393462

Inventors:

Kenneth E. Stephenson - Princeton NJ, US

International Classification:

G01V 5/10
G21B 1/11

US Classification:

2502691, 376108, 376119

Abstract:

A neutron generator includes a sealed envelope providing a low pressure environment for a gas. One end of the envelope defines an ion source chamber. A target electrode is disposed at the other end of the envelope. An extracting electrode is spaced apart from the target electrode by an accelerating gap. The extracting electrode bounds the ion source chamber. A dispenser cathode electrode and grid electrode are disposed in the ion source chamber for inducing ionization in the ion source chamber. The dispenser cathode electrode, the grid electrode and the extracting electrode operate at a positive high voltage potential and the target electrode operates at or near ground potential. This configuration provides an electric field gradient that accelerates ions towards the target electrode to induce collisions of ions with target material, thereby causing fusion reactions that generate neutrons. High voltage power supply circuit means supplies a positive high voltage signal to the electrodes of the ion source. The positive high voltage signal has a low voltage signal component floating on a positive high voltage signal component. For the dispensing cathode electrode, the low voltage signal component can be a DC or AC signal suitable for emitting electrons from the dispensing cathode electrode. For the grid electrode, the low voltage signal component can be a positive pulsed-mode signal (preferably with magnitude in the range between 100 to 300 volts). High voltage insulation surrounds and electrically insulates the high voltage power supply circuit means. Other ion source electrode configurations, such as cold cathode (Penning) ion source and RF-driven ion source, can also be used.

US Patent:

20120197529, Aug 2, 2012

Filed:

May 21, 2010

Appl. No.:

13/321933

Inventors:

Kenneth E. Stephenson - Princeton NJ, US
David Rose - Sugar Land TX, US
Christian Stoller - Princeton Junction NJ, US
Donna Simonetti - Hamilton NJ, US

International Classification:

G06F 19/00
G01V 5/10

US Classification:

702 8, 2502696

Abstract:

Systems, methods, and devices for inelastic gamma-ray logging are provided. In one embodiment, such a method includes emitting neutrons into a subterranean formation from a downhole tool to produce inelastic gamma-rays, detecting a portion of the inelastic gamma-rays that scatter back to the downhole tool to obtain an inelastic gamma-ray signal, and determining a property of the subterranean formation based at least in part on the inelastic gamma-ray signal. The inelastic gamma-ray signal may be substantially free of epithermal and thermal neutron capture background.

US Patent:

20130211724, Aug 15, 2013

Filed:

Jun 27, 2011

Appl. No.:

13/807681

Inventors:

John B. Fitzgerald - Cambridge, GB
Kenneth E. Stephenson - Plainsboro NJ, US

Assignee:

SCHLUMBERGER TECHNOLOGY CORPORATION - Sugar Land TX

International Classification:

G01V 5/10

US Classification:

702 8, 2502696, 250254

Abstract:

The present disclosure is intended to overcome the problem of hydrogen contamination of the density signal. The approach is to compute the neutron capture portion of the total gamma ray counts and subtract it from the total counts resulting in a pure inelastic gamma ray measurement.

US Patent:

20130256520, Oct 3, 2013

Filed:

Mar 28, 2012

Appl. No.:

13/432780

Inventors:

Roman Korkin - Lawrenceville NJ, US
Wolfgang Ziegler - Hightstown NJ, US
Kenneth Stephenson - Plainsboro NJ, US

International Classification:

G01V 5/04
G01T 3/06

US Classification:

250256, 250361 R, 250362

Abstract:

A neutron detector is provided which may include a neutron converting layer, and a scintillator layer adjacent the neutron converting layer. The neutron detector may further include a photomultiplier adjacent the scintillator layer. By way of example, the neutron detector may be used in a well logging apparatus to determine a neutron flux incident upon the neutron converting layer, and thereby determine the neutron porosity of a geological formation around a wellbore.

US Patent:

20130299713, Nov 14, 2013

Filed:

Nov 11, 2011

Appl. No.:

13/885667

Inventors:

Kenneth Stephenson - Plainsboro NJ, US
Christian Stoller - Princeton Junction NJ, US
Olivier G. Philip - Ewing NJ, US

Assignee:

SCHLUMBERGER TECHNOLOGY CORPORATION - Sugar Land TX

International Classification:

G01T 3/00

US Classification:

25039001

Abstract:

A neutron detecting device using a neutron-reactive material as the source of charged particles to feed conventional dynode-based electron multiplier which not gas-filled (i.e., with He). The detector comprises a neutron-reacting material that produces charged particles, coupled with an electron multiplier that is known for use in photomultipliers. The neutron-reacting material is deposited on a substrate at the entrance to the electron multiplier. Charged particles from the neutron-reacting material impinge on the first dynode of the electron multiplier, where, in turn, electrons are generated. The secondary electrons are collected by a second dynode, and the charge so collected is amplified in each succeeding dynode stage in a cascade effect. The charge pulse from the anode is processed by subsequent pulse processing electronics and counting electronics to provide a count rate that is proportional to the neutron flux incident on the neutron-reacting material.

US Patent:

47106751, Dec 1, 1987

Filed:

Apr 29, 1985

Appl. No.:

6/728135

Inventors:

Kenneth E. Stephenson - Pennington NJ

Assignee:

Sangamo Weston, Inc. - Norcross GA

International Classification:

H01J 4306
H01J 4322

US Classification:

313532

Abstract:

A photomultiplier includes a solid disk dynode and a pair of annular guiding electrodes disposed about the disk dynode transversely along the central axis of the photomultiplier tube on opposite sides of the dynode. The secondary and subsequent dynodes may be of conventional (e. g. venetian blind) construction or of solid disk construction. The solid disk dynode and guiding structure exhibits improved photoelectron pulse-height resolution and a better signal-to-noise ratio than a conventional venetian blind type dynode. In addition, the solid dynode structure is less susceptible to physical shock than conventional photomultiplier dynode designs.

US Patent:

20140339408, Nov 20, 2014

Filed:

May 15, 2013

Appl. No.:

13/895130

Inventors:

- Sugar Land TX, US
Christian Stoller - Princeton Junction NJ, US
Kenneth E. Stephenson - Plainsboro NJ, US

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

G01V 5/12
G01T 1/20

US Classification:

250256, 2504831, 250361 R

Abstract:

A radiation detector package includes a support apparatus at least part of which is constructed from a naturally occurring radioactive material. A scintillator is associated with the support apparatus. The support may include a detector housing carrying a photodetector and the scintillator, and the detector housing may be constructed from the naturally occurring radioactive material.