Marc H Simpson

US Patent:

6471888, Oct 29, 2002

Filed:

Dec 12, 1995

Appl. No.:

08/571307

Inventors:

John T. Mihalczo - Oak Ridge TN
Marc L. Simpson - Knoxville TN
Stephanie A. McElhaney - Oak Ridge TN

Assignee:

UT-Battelle, LLC - Oak Ridge TN

International Classification:

G01T 1164

US Classification:

25230117, 25230118, 25230134, 25230135, 25230136, 2504721, 2504831, 2504842, 2504843, 25039011

Abstract:

Simultaneous measurement of neutron flux and temperature is provided by a single sensor which includes a phosphor mixture having two principal constituents. The first constituent is a neutron sensitive Li F and the second is a rare-earth activated Y O thermophosphor. The mixture is coated on the end of a fiber optic, while the opposite end of the fiber optic is coupled to a light detector. The detected light scintillations are quantified for neutron flux determination, and the decay is measured for temperature determination.

US Patent:

56802528, Oct 21, 1997

Filed:

Mar 23, 1995

Appl. No.:

8/409390

Inventors:

David N. Sitter - Knoxville TN
Marc L. Simpson - Knoxville TN

Assignee:

Martin Marietta Energy Systems, Inc. - Oak Ridge TN

International Classification:

G02B 528
G02B 2744
G02B 2742

US Classification:

359566

Abstract:

A miniature lens system that corrects for imaging and chromatic aberrations, the lens system being fabricated from primarily commercially-available components. A first element at the input to a lens housing is an aperture stop. A second optical element is a refractive element with a diffractive element closely coupled to, or formed a part of, the rear surface of the refractive element. Spaced closely to the diffractive element is a baffle to limit the area of the image, and this is closely followed by a second refractive lens element to provide the final correction. The image, corrected for aberrations exits the last lens element to impinge upon a detector plane were is positioned any desired detector array. The diffractive element is fabricated according to an equation that includes, as variables, the design wavelength, the index of refraction and the radius from an optical axis of the lens system components.

US Patent:

61234559, Sep 26, 2000

Filed:

May 2, 1997

Appl. No.:

8/850239

Inventors:

David L. Beshears - Knoxville TN
David N. Sitter - Tucson AZ
William H. Andrews - Oliver Springs TN
Marc L. Simpson - Knoxville TN
Ruth A. Abston - Vienna, AT
Michael R. Cates - Oak Ridge TN
Steve W. Allison - Knoxville TN

Assignee:

American Iron and Steel Institute - Washington DC

International Classification:

G01K 1120
G01K 1112

US Classification:

374161

Abstract:

An apparatus for measuring the temperature of a moving substrate includes an air gun with a powder inlet port in communication with the outlet port of a powder reservoir, an air inlet port in communication with a pressurized air source, and an outlet nozzle spaced from and directed toward the moving substrate. The air gun is activated by the air pulses to spray controlled amounts of the powdered phosphor onto the moving substrate, where the phosphor assumes the temperature of the moving substrate. A laser produces light pulses, and optics direct the light pulses onto the phosphor on the moving substrate, in response to which the phosphor emits a luminescence with a decay rate indicative of the temperature of the phosphor. A collection lens is disposed to focus the luminescence, and a photodetector detects the luminescence focused by the collection lens and produces an electrical signal that is characteristic of the brightness of the luminescence. A processor analyzes the electrical signal to determine the decay characteristic of the luminescence and to determine the temperature of the phosphor from the decay characteristic.

US Patent:

53520408, Oct 4, 1994

Filed:

Apr 8, 1994

Appl. No.:

8/225363

Inventors:

John T. Mihalczo - Oak Ridge TN
Marc L. Simpson - Knoxville TN
Stephanie A. McElhaney - Oak Ridge TN

Assignee:

Martin Marietta Energy Systems, Inc. - Oak Ridge TN

International Classification:

G01J 500

US Classification:

374131

Abstract:

Simultaneous measurement of neutron flux and temperature is provided by a single sensor which includes a phosphor mixture having two principal constituents. The first constituent is a neutron sensitive 6LiF and the second is a rare-earth activated Y203 thermophosphor. The mixture is coated on the end of a fiber optic, while the opposite end of the fiber optic is coupled to a light detector. The detected light scintillations are quantified for neutron flux determination, and the decay is measured for temperature determination.

US Patent:

59495391, Sep 7, 1999

Filed:

Nov 10, 1997

Appl. No.:

8/966657

Inventors:

Charles L. Britton - Alcoa TN
David L. Beshears - Knoxville TN
Marc L. Simpson - Knoxville TN
Michael R. Cates - Oak Ridge TN
Steve W. Allison - Knoxville TN

Assignee:

American Iron and Steel Institute - Washington DC

International Classification:

G01J 330

US Classification:

356317

Abstract:

A method for determining the decay-time constant of a fluorescing phosphor is provided, together with an apparatus for performing the method. The apparatus includes a photodetector for detecting light emitted by a phosphor irradiated with an excitation pulse and for converting the detected light into an electrical signal. The apparatus further includes a differentiator for differentiating the electrical signal and a zero-crossing discrimination circuit that outputs a pulse signal having a pulse width corresponding to the time period between the start of the excitation pulse and the time when the differentiated electrical signal reaches zero. The width of the output pulse signal is proportional to the decay-time constant of the phosphor.

US Patent:

59862726, Nov 16, 1999

Filed:

Apr 19, 1999

Appl. No.:

9/293916

Inventors:

Charles L. Britton - Alcoa TN
David L. Beshears - Knoxville TN
Marc L. Simpson - Knoxville TN
Michael R. Cates - Oak Ridge TN
Steve W. Allison - Knoxville TN

Assignee:

American Iron and Steel Institute - Washington DC

International Classification:

G01K 1100

US Classification:

2504591

Abstract:

A method for determining the temperature of a fluorescing phosphor is provided, together with an apparatus for performing the method. The apparatus includes a photodetector for detecting light emitted by a phosphor irradiated with an excitation pulse and for converting the detected light into an electrical signal. The apparatus further includes a differentiator for differentiating the electrical signal and a zero-crossing discrimination circuit that outputs a pulse signal having a pulse width corresponding to the time period between the start of the excitation pulse and the time when the differentiated electrical signal reaches zero. The width of the output pulse signal is proportional to the decay-time constant of the phosphor.