Dr. Stephen T. Kreger Profile

Dr. Stephen T. Kreger

Technology Development Lead at Luna Innovations Inc

SPIE Involvement:

Author

Publications (23)

Proceedings Article | 14 May 2019 Presentation + Paper

Distributed polarization state sensing with optical frequency domain reflectometry

Stephen Kreger, Emily Templeton, Daniel Kominsky, Brian Templeton

Proceedings Volume 11000, 1100006 (2019) https://doi.org/10.1117/12.2519184

KEYWORDS: Polarization, Birefringence, Sensors, Reflectometry, Fiber optics sensors, Spatial resolution, Interferometers

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Proceedings Article | 27 April 2017 Presentation + Paper

Optical frequency domain reflectometry for aerospace applications

Stephen Kreger, Osgar John Ohanian, Naman Garg, Matthew Castellucci, Dan Kominski, Nur Aida Abdul Rahim, Matthew Davis, Noah Beaty, James Jeans, Emily Templeton, J. Pedrazzani

Proceedings Volume 10208, 1020803 (2017) https://doi.org/10.1117/12.2262845

KEYWORDS: Sensors, Absorption, Sensor calibration, Composites, Aerospace engineering, Fiber optics sensors, Reflectometry, Data acquisition, Structural health monitoring, Finite element methods, Fiber Bragg gratings, Temperature metrology, Defect detection, Calibration

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Proceedings Article | 12 May 2016 Paper

Optical frequency domain reflectometry: principles and applications in fiber optic sensing

Stephen Kreger, Nur Aida Abdul Rahim, Naman Garg, Sandra Klute, Daniel Metrey, Noah Beaty, James Jeans, Robert Gamber

Proceedings Volume 9852, 98520T (2016) https://doi.org/10.1117/12.2229057

KEYWORDS: Fiber optics sensors, Sensors, Fiber Bragg gratings, Composites, Fiber optics sensors, Sensors, Reflectometry, Composites, Fourier transforms, Computer aided design, Spatial resolution, Optical fibers, Structured optical fibers

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Proceedings Article | 13 May 2015 Paper

Distributed Rayleigh scatter dynamic strain sensing above the scan rate with optical frequency domain reflectometry

Stephen Kreger, Justin Klein, Nur Aida Abdul Rahim, Joseph Bos

Proceedings Volume 9480, 948006 (2015) https://doi.org/10.1117/12.2177578

KEYWORDS: Actuators, Geometrical optics, Spatial resolution, Sensors, Fiber optics sensors, Motion measurement, Reflectometry, Fiber lasers, Laser scattering, Phase measurement

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Proceedings Article | 29 May 2013 Paper

High resolution, high sensitivity, dynamic distributed structural monitoring using optical frequency domain reflectometry

Stephen Kreger, Alex Sang, Naman Garg, Julia Michel

Proceedings Volume 8722, 87220D (2013) https://doi.org/10.1117/12.2018237

KEYWORDS: Sensors, Spatial resolution, Fiber Bragg gratings, Digital signal processing, Fiber optics sensors, Reflectometry, Signal processing, Optical fibers, Head, Structural monitoring

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Proceedings Article | 17 May 2011 Paper

Millimeter resolution distributed dynamic strain measurements using optical frequency domain reflectometry

A. Sang, M. Froggatt, S. Kreger, D. Gifford

Proceedings Volume 7753, 77532S (2011) https://doi.org/10.1117/12.885946

KEYWORDS: Optical fibers, Spatial resolution, Transducers, Optical testing, Data acquisition, Aluminum, Fiber Bragg gratings, Digital signal processing, Reflectometry, Calibration

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Proceedings Article | 17 May 2011 Paper

High precision, high sensitivity distributed displacement and temperature measurements using OFDR-based phase tracking

Dawn Gifford, Mark Froggatt, Stephen Kreger

Proceedings Volume 7753, 77533I (2011) https://doi.org/10.1117/12.885131

KEYWORDS: Temperature metrology, Fiber Bragg gratings, Spatial resolution, Phase measurement, Fiber optics sensors, Optical fibers, Reflectometry, Sensors, Precision measurement, Phase shift keying

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Proceedings Article | 9 September 2010 Paper

Strain measurements of a fiber loop rosette using high spatial resolution Rayleigh scatter distributed sensing

Dawn Gifford, Alex Sang, Steven Kreger, Mark Froggatt

Proceedings Volume 7653, 765333 (2010) https://doi.org/10.1117/12.866536

KEYWORDS: Spatial resolution, Optical fibers, Geometrical optics, Reflectometry, Fiber optics sensors, Temperature metrology, Sensors, Fiber Bragg gratings, Aluminum, Distance measurement

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Proceedings Article | 28 April 2009 Paper

Distributed strain and temperature sensing in plastic optical fiber using Rayleigh scatter

Stephen Kreger, Alex Sang, Dawn Gifford, Mark Froggatt

Proceedings Volume 7316, 73160A (2009) https://doi.org/10.1117/12.821353

KEYWORDS: Phase only filters, Optical fibers, Spatial resolution, Fiber Bragg gratings, Temperature metrology, Polymer optical fibers, Calibration, Backscatter, Optical sensing, Multimode fibers

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Proceedings Article | 12 October 2007 Paper

Swept-wavelength interferometric interrogation of fiber Rayleigh scatter for distributed sensing applications

Dawn Gifford, Steven Kreger, Alex Sang, Mark Froggatt, Roger Duncan, Matthew Wolfe, Brian Soller

Proceedings Volume 6770, 67700F (2007) https://doi.org/10.1117/12.734931

KEYWORDS: Temperature metrology, Spatial resolution, Fiber Bragg gratings, Calibration, Interferometry, Scatter measurement, Spectral resolution, Sensors, Optical fibers, Polarization

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Proceedings Article | 10 April 2007 Paper

High-resolution extended distance distributed fiber-optic sensing using Rayleigh backscatter

Stephen Kreger, Dawn Gifford, Mark Froggatt, Alex Sang, Roger Duncan, Matthew Wolfe, Brian Soller

Proceedings Volume 6530, 65301R (2007) https://doi.org/10.1117/12.720913

KEYWORDS: Spatial resolution, Backscatter, Multimode fibers, Optical fibers, Temperature metrology, Spectral resolution, Sensors, Fiber Bragg gratings, Reflectivity, Interferometers

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Proceedings Article | 10 April 2007 Paper

High-accuracy fiber-optic shape sensing

Roger Duncan, Mark Froggatt, Stephen Kreger, Ryan Seeley, Dawn Gifford, Alexander Sang, Matthew Wolfe

Proceedings Volume 6530, 65301S (2007) https://doi.org/10.1117/12.720914

KEYWORDS: Sensors, Fiber Bragg gratings, Fiber optics sensors, Optical fibers, Spatial frequencies, Fiber optics, Calibration, Fiber optics tests, Precision measurement, Scatter measurement

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Proceedings Article | 16 May 2005 Paper

Failure mechanisms of fiber optic sensors placed in composite materials

Eric Udd, Mike Winz, Stephen Kreger, Dirk Heider

Proceedings Volume 5758, (2005) https://doi.org/10.1117/12.603626

KEYWORDS: Composites, Fiber optics sensors, Optical fibers, Sensors, Optical coatings, Carbon, Epoxies, Genetic algorithms, Connectors, Bridges

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Proceedings Article | 16 May 2005 Paper

Damage evaluation and analysis of composite pressure vessels using fiber Bragg gratings to determine structural health

Marley Kunzler, Eric Udd, Stephen Kreger, Mont Johnson, Vaughn Henrie

Proceedings Volume 5758, (2005) https://doi.org/10.1117/12.599890

KEYWORDS: Composites, Fiber optics sensors, Sensors, Fiber Bragg gratings, Ultrasonics, Algorithm development, Nondestructive evaluation, Imaging systems, Manufacturing, Roads

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Proceedings Article | 27 July 2004 Paper

Modeling and experimental strain measurements on a nonhomogeneous cylinder under transverse load

John Viator, Stephen Kreger, Michele Winz, Eric Udd

Proceedings Volume 5384, (2004) https://doi.org/10.1117/12.541589

KEYWORDS: Fiber Bragg gratings, Optical fibers, Data modeling, Fiber optics sensors, Sensors, Polarization, Phase modulation, Silica, Roads, Environmental sensing

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Proceedings Article | 20 November 2003 Paper

Nondestructive evaluation of composite materials using multi-axis fiber grating strain sensors

Eric Udd, Stephen Kreger, Sean Calvert, Marley Kunzler, Tad Taylor

Proceedings Volume 5278, (2003) https://doi.org/10.1117/12.544357

KEYWORDS: Fiber optics sensors, Sensors, Composites, Bridges, Optical fibers, Adhesives, Epoxies, Titanium, Roads, Optical coatings

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Proceedings Article | 20 November 2003 Paper

Monitoring of advanced composite weave structures using multi-axis fiber grating strain sensors

Katy Davol, Eric Udd, Stephen Kreger, Marley Kunzler, Marty Laylor, Dirk Heider, Zhicheng Yu

Proceedings Volume 5278, (2003) https://doi.org/10.1117/12.544457

KEYWORDS: Sensors, Composites, Fiber optics sensors, Structured optical fibers, Polarization, Fiber optics, Roads, Fiber optics tests, Refraction, Fiber Bragg gratings

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Proceedings Article | 27 June 2002 Paper

Using multi-axis fiber grating strain sensors to measure transverse strain and transverse strain gradients in composite materials with complex weave structures

Catherine Black, Eric Udd, Whitten Schulz, Stephen Kreger, Marley Kunzler, Tad Taylor, Ross Lumsden, Dirk Heider, Zhicheng Yu

Proceedings Volume 4694, (2002) https://doi.org/10.1117/12.472613

KEYWORDS: Composites, Sensors, Fiber optics sensors, Structured optical fibers, Polarization, Temperature metrology, Fiber polarizers, Fiber optics tests, Fiber optics, 3D metrology

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Proceedings Article | 3 August 2001 Paper

Fiber grating sensor systems for traffic monitoring

Eric Udd, Marley Kunzler, Harold Laylor, Whitten Schulz, Stephen Kreger, John Corones, Robert McMahon, Steven Soltesz, Robert Edgar

Proceedings Volume 4337, (2001) https://doi.org/10.1117/12.435627

KEYWORDS: Sensors, Bridges, Fiber optics sensors, Roads, Demodulation, Epoxies, Fiber reinforced polymers, Optical design, Light sources, Optical filters

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Proceedings Article | 30 November 1999 Paper

Variation in optical disk retardance measurements

Kent Rochford, Stephen Kreger, John West

Proceedings Volume 3806, (1999) https://doi.org/10.1117/12.371163

KEYWORDS: Birefringence, Optical discs, Polarization, Optical testing, Wave plates, Temperature metrology, Polarimetry, Calibration, Optics manufacturing, Polymers

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Proceedings Article | 28 June 1999 Paper

Variation in optical disk birefringence measurements

Kent Rochford, Stephen Kreger, John West

Proceedings Volume 3864, 38641Z (1999) https://doi.org/10.1117/12.997588

KEYWORDS: Birefringence, Optical discs, Optical testing, Wave plates, Polarization, Temperature metrology, Polarimetry, Compact discs, Signal detection, Optics manufacturing

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Proceedings Article | 10 April 1997 Paper

Solid state photon counters for scanned image acquisition: thermal and electronic saturation effects

Stephen Kreger, Thomas Brown

Proceedings Volume 2984, (1997) https://doi.org/10.1117/12.271270

KEYWORDS: Capacitance, Avalanche photodetectors, Solid state electronics, Photon counting, Diodes, Signal to noise ratio, Image acquisition, Time correlated photon counting, Sensors, Image quality

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Proceedings Article | 10 April 1996 Paper

Application of avalanche photodiodes to confocal and confocal florescence microscopy

Thomas Brown, Stephen Kreger

Proceedings Volume 2655, (1996) https://doi.org/10.1117/12.237495

KEYWORDS: Confocal microscopy, Photon counting, Sensors, Luminescence, Avalanche photodetectors, Avalanche photodiodes, Microscopy, Image acquisition, Solid state electronics, Diodes

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