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Robert Huber - One of the best experts on this subject based on the ideXlab platform.

  • Fourier Domain Mode Locking (FDML): A New Laser Operating Regime and Applications for Biomedical Imaging, Profilometry, Ranging and Sensing
    Frontiers in Optics, 2009
    Co-Authors: Robert Huber
    Abstract:

    Fourier Domain Mode Locking (FDML) is a new stationary Operating Regime of lasers, generating narrowband, rapidly wavelength swept output waveforms. The FDML mechanism and applications for biomedical imaging, coherent sensing and spectroscopy are discussed. (Advanced Solid-State Photonics, 2009). Download original .PDF file here:

  • Fourier Domain Mode Locking (FDML): A New Laser Operating Regime and Applications for Biomedical Imaging, Profilometry, Ranging and Sensing
    Advanced Solid-State Photonics, 2009
    Co-Authors: Robert Huber
    Abstract:

    Fourier Domain Mode Locking (FDML) is a new stationary Operating Regime of lasers, generating narrowband, rapidly wavelength swept output waveforms. The FDML mechanism and applications for biomedical imaging, coherent sensing and spectroscopy are discussed.

  • fourier domain mode locking fdml a new laser Operating Regime and applications for optical coherence tomography
    Optics Express, 2006
    Co-Authors: Robert Huber, Maciej Wojtkowski, James G. Fujimoto
    Abstract:

    We demonstrate a new technique for frequency-swept laser operation--Fourier domain mode locking (FDML)--and its application for swept-source optical coherence tomography (OCT) imaging. FDML is analogous to active laser mode locking for short pulse generation, except that the spectrum rather than the amplitude of the light field is modulated. High-speed, narrowband optical frequency sweeps are generated with a repetition period equal to the fundamental or a harmonic of cavity round-trip time. An FDML laser is constructed using a long fiber ring cavity, a semiconductor optical amplifier, and a tunable fiber Fabry-Perot filter. Effective sweep rates of up to 290 kHz are demonstrated with a 105 nm tuning range at 1300 nm center wavelength. The average output power is 3 mW directly from the laser and 20 mW after post-amplification. Using the FDML laser for swept-source OCT, sensitivities of 108 dB are achieved and dynamic linewidths are narrow enough to enable imaging over a 7 mm depth with only a 7.5 dB decrease in sensitivity. We demonstrate swept-source OCT imaging with acquisition rates of up to 232,000 axial scans per second. This corresponds to 906 frames/second with 256 transverse pixel images, and 3.5 volumes/second with a 256×128×256 voxel element 3-D OCT data set. The FDML laser is ideal for swept-source OCT imaging, thus enabling high imaging speeds and large imaging depths.

  • Fourier Domain Mode Locking (FDML): A new laser Operating Regime and applications for optical coherence tomography 8 / OPTICS EXPRESS 3225
    Optics Express, 2006
    Co-Authors: Robert Huber, Maciej Wojtkowski, James G. Fujimoto
    Abstract:

    We demonstrate a new technique for frequency-swept laser operation--Fourier domain mode locking (FDML)--and its application for swept-source optical coherence tomography (OCT) imaging. FDML is analogous to active laser mode locking for short pulse generation, except that the spectrum rather than the amplitude of the light field is modulated. High-speed, narrowband optical frequency sweeps are generated with a repetition period equal to the fundamental or a harmonic of cavity round-trip time. An FDML laser is constructed using a long fiber ring cavity, a semiconductor optical amplifier, and a tunable fiber Fabry-Perot filter. Effective sweep rates of up to 290 kHz are demonstrated with a 105 nm tuning range at 1300 nm center wavelength. The average output power is 3 mW directly from the laser and 20 mW after post-amplification. Using the FDML laser for swept-source OCT, sensitivities of 108 dB are achieved and dynamic linewidths are narrow enough to enable imaging over a 7 mm depth with only a 7.5 dB decrease in sensitivity. We demonstrate swept-source OCT imaging with acquisition rates of up to 232,000 axial scans per second. This corresponds to 906 frames/second with 256 transverse pixel images, and 3.5 volumes/second with a 256x128x256 voxel element 3-D OCT data set. The FDML laser is ideal for swept-source OCT imaging, thus enabling high imaging speeds and large imaging depths. "Amplified, frequency swept lasers for frequency domain reflectometry and OCT imaging: design and scaling principles," Opt. Express 13, 3513-3528 (2005). http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-9-3513. 9. M. A. Choma, K. Hsu, and J. Izatt, "Swept source optical coherence tomography using an all-fiber 1300-nm ring laser source," J. Biomed. Opt. 10, 044009 (2005). Cable, "Three-dimensional and C-mode OCT imaging with a compact, frequency swept laser source at 1300 nm," Opt. Express 13, 10523-10538 (2005). http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-26-10523. 11. Y. Yasuno, V. Madjarova, S. Makita, M. Akiba, A. Morosawa, C. Chong, T. Sakai, K. Chan, M. Itoh, and T. Yatagai, "Three-dimensional and high-speed swept-source optical coherence tomography for in vivo investigation of human anterior eye segments," Opt. Express 13, 10652-10664 (2005). http://www.opticsexpress.org/abstract.cfm?id=86669. 12. W. Y. Oh, S. H. Yun, G. J. Tearney, and B. E. Bouma, "115 kHz tuning repetition rate ultrahigh-speed wavelength-swept semiconductor laser," Opt. Lett. 30, 3159-3161 (2005). 13. S. T. Sanders, J. A. Baldwin, T. P. Jenkins, D. S. Baer, and R. K. Hanson, "Diode-laser sensor for monitoring multiple combustion parameters in pulse detonation engines," P. Combust. Inst. 28, 587-594 (2000). 14. J. Wang, S. T. Sanders, J. B. Jeffries, and R. K. Hanson, "Oxygen measurements at high pressures with vertical cavity surface-emitting lasers," Appl. Phys. B 72, 865-872 (2001). 15. G. Totschnig, M. Lackner, R. Shau, M. Ortsiefer, J. Rosskopf, M. C. Amann, and F. Winter, "1.8 mu m vertical-cavity surface-emitting laser absorption measurements of HCl, H2O and CH4," Meas. Sci. Technol. 14, 472-478 (2003). 16. A. A. Bol'shakov, B. A. Cruden, and S. P. Sharma, "Determination of gas temperature and thermometric species in inductively coupled plasmas by emission and diode laser absorption," Plasma Sci. Technol. 13, 691-700 (2004). 17. L. A. Kranendonk, R. J. Bartula, and S. T. Sanders, "Modeless operation of a wavelength-agile laser by high-speed cavity length changes," Opt. Express 13, 1498-1507 (2005). http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-5-1498. 18. W. Eickhoff and R. Ulrich, "Optical frequency-domain reflectometry in single-mode fiber," Appl. Phys. Lett. 39, 693-695 (1981). 19. R. Passy, N. Gisin, J. P. Vonderweid, and H. H. Gilgen, "Experimental and theoretical investigations of coherent Ofdr with semiconductor-laser sources," J. Lightwave Technol. 12, 1622-1630 (1994). 20. U. Glombitza and E. Brinkmeyer, "Coherent frequency-domain reflectometry for characterization of single-mode integrated-optical wave-guides," J. Lightwave Technol. 11, 1377-1384 (1993). 21. H. Barfuss and E. Brinkmeyer, "Modified optical frequency-domain reflectometry with high spatial-resolution for components of integrated optic systems," J. Lightwave Technol. 7, 3-10 (1989). 22. M. A. Choma, M. V. Sarunic, C. Yang, and J. Izatt, "Sensitivity advantage of swept source and Fourier domain optical coherence tomography," Opt. Express 11, 2183-2189 (2003). http://www.opticsexpress.org/abstract.cfm?URI=OPEX-11-18-2183. 23. M. Wojtkowski, R. Leitgeb, A. Kowalczyk, T. Bajraszewski, and A. F. Fercher, "In vivo human retinal imaging by Fourier domain optical coherence tomography," J. Biomed. Opt. 7, 457-463 (2002). 24. S. H. Yun, G. J. Tearney, B. E. Bouma, B. H. Park, and J. F. de Boer, "High-speed spectral-domain optical coherence tomography at 1.3 mu m wavelength," Opt. Express 11, 3598-3604 (2003). http://www.opticsexpress.org/abstract.cfm?URI=OPEX-11-26-3598. 25. "In vivo high-resolution video-rate spectral-domain optical coherence tomography of the human retina and optic nerve," Opt. Express 12, 367-376 (2004). http://www.opticsexpress.org/abstract.cfm?URI=OPEX-12-3-367.

James G. Fujimoto - One of the best experts on this subject based on the ideXlab platform.

  • fourier domain mode locking fdml a new laser Operating Regime and applications for optical coherence tomography
    Optics Express, 2006
    Co-Authors: Robert Huber, Maciej Wojtkowski, James G. Fujimoto
    Abstract:

    We demonstrate a new technique for frequency-swept laser operation--Fourier domain mode locking (FDML)--and its application for swept-source optical coherence tomography (OCT) imaging. FDML is analogous to active laser mode locking for short pulse generation, except that the spectrum rather than the amplitude of the light field is modulated. High-speed, narrowband optical frequency sweeps are generated with a repetition period equal to the fundamental or a harmonic of cavity round-trip time. An FDML laser is constructed using a long fiber ring cavity, a semiconductor optical amplifier, and a tunable fiber Fabry-Perot filter. Effective sweep rates of up to 290 kHz are demonstrated with a 105 nm tuning range at 1300 nm center wavelength. The average output power is 3 mW directly from the laser and 20 mW after post-amplification. Using the FDML laser for swept-source OCT, sensitivities of 108 dB are achieved and dynamic linewidths are narrow enough to enable imaging over a 7 mm depth with only a 7.5 dB decrease in sensitivity. We demonstrate swept-source OCT imaging with acquisition rates of up to 232,000 axial scans per second. This corresponds to 906 frames/second with 256 transverse pixel images, and 3.5 volumes/second with a 256×128×256 voxel element 3-D OCT data set. The FDML laser is ideal for swept-source OCT imaging, thus enabling high imaging speeds and large imaging depths.

  • Fourier Domain Mode Locking (FDML): A new laser Operating Regime and applications for optical coherence tomography 8 / OPTICS EXPRESS 3225
    Optics Express, 2006
    Co-Authors: Robert Huber, Maciej Wojtkowski, James G. Fujimoto
    Abstract:

    We demonstrate a new technique for frequency-swept laser operation--Fourier domain mode locking (FDML)--and its application for swept-source optical coherence tomography (OCT) imaging. FDML is analogous to active laser mode locking for short pulse generation, except that the spectrum rather than the amplitude of the light field is modulated. High-speed, narrowband optical frequency sweeps are generated with a repetition period equal to the fundamental or a harmonic of cavity round-trip time. An FDML laser is constructed using a long fiber ring cavity, a semiconductor optical amplifier, and a tunable fiber Fabry-Perot filter. Effective sweep rates of up to 290 kHz are demonstrated with a 105 nm tuning range at 1300 nm center wavelength. The average output power is 3 mW directly from the laser and 20 mW after post-amplification. Using the FDML laser for swept-source OCT, sensitivities of 108 dB are achieved and dynamic linewidths are narrow enough to enable imaging over a 7 mm depth with only a 7.5 dB decrease in sensitivity. We demonstrate swept-source OCT imaging with acquisition rates of up to 232,000 axial scans per second. This corresponds to 906 frames/second with 256 transverse pixel images, and 3.5 volumes/second with a 256x128x256 voxel element 3-D OCT data set. The FDML laser is ideal for swept-source OCT imaging, thus enabling high imaging speeds and large imaging depths. "Amplified, frequency swept lasers for frequency domain reflectometry and OCT imaging: design and scaling principles," Opt. Express 13, 3513-3528 (2005). http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-9-3513. 9. M. A. Choma, K. Hsu, and J. Izatt, "Swept source optical coherence tomography using an all-fiber 1300-nm ring laser source," J. Biomed. Opt. 10, 044009 (2005). Cable, "Three-dimensional and C-mode OCT imaging with a compact, frequency swept laser source at 1300 nm," Opt. Express 13, 10523-10538 (2005). http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-26-10523. 11. Y. Yasuno, V. Madjarova, S. Makita, M. Akiba, A. Morosawa, C. Chong, T. Sakai, K. Chan, M. Itoh, and T. Yatagai, "Three-dimensional and high-speed swept-source optical coherence tomography for in vivo investigation of human anterior eye segments," Opt. Express 13, 10652-10664 (2005). http://www.opticsexpress.org/abstract.cfm?id=86669. 12. W. Y. Oh, S. H. Yun, G. J. Tearney, and B. E. Bouma, "115 kHz tuning repetition rate ultrahigh-speed wavelength-swept semiconductor laser," Opt. Lett. 30, 3159-3161 (2005). 13. S. T. Sanders, J. A. Baldwin, T. P. Jenkins, D. S. Baer, and R. K. Hanson, "Diode-laser sensor for monitoring multiple combustion parameters in pulse detonation engines," P. Combust. Inst. 28, 587-594 (2000). 14. J. Wang, S. T. Sanders, J. B. Jeffries, and R. K. Hanson, "Oxygen measurements at high pressures with vertical cavity surface-emitting lasers," Appl. Phys. B 72, 865-872 (2001). 15. G. Totschnig, M. Lackner, R. Shau, M. Ortsiefer, J. Rosskopf, M. C. Amann, and F. Winter, "1.8 mu m vertical-cavity surface-emitting laser absorption measurements of HCl, H2O and CH4," Meas. Sci. Technol. 14, 472-478 (2003). 16. A. A. Bol'shakov, B. A. Cruden, and S. P. Sharma, "Determination of gas temperature and thermometric species in inductively coupled plasmas by emission and diode laser absorption," Plasma Sci. Technol. 13, 691-700 (2004). 17. L. A. Kranendonk, R. J. Bartula, and S. T. Sanders, "Modeless operation of a wavelength-agile laser by high-speed cavity length changes," Opt. Express 13, 1498-1507 (2005). http://www.opticsexpress.org/abstract.cfm?URI=OPEX-13-5-1498. 18. W. Eickhoff and R. Ulrich, "Optical frequency-domain reflectometry in single-mode fiber," Appl. Phys. Lett. 39, 693-695 (1981). 19. R. Passy, N. Gisin, J. P. Vonderweid, and H. H. Gilgen, "Experimental and theoretical investigations of coherent Ofdr with semiconductor-laser sources," J. Lightwave Technol. 12, 1622-1630 (1994). 20. U. Glombitza and E. Brinkmeyer, "Coherent frequency-domain reflectometry for characterization of single-mode integrated-optical wave-guides," J. Lightwave Technol. 11, 1377-1384 (1993). 21. H. Barfuss and E. Brinkmeyer, "Modified optical frequency-domain reflectometry with high spatial-resolution for components of integrated optic systems," J. Lightwave Technol. 7, 3-10 (1989). 22. M. A. Choma, M. V. Sarunic, C. Yang, and J. Izatt, "Sensitivity advantage of swept source and Fourier domain optical coherence tomography," Opt. Express 11, 2183-2189 (2003). http://www.opticsexpress.org/abstract.cfm?URI=OPEX-11-18-2183. 23. M. Wojtkowski, R. Leitgeb, A. Kowalczyk, T. Bajraszewski, and A. F. Fercher, "In vivo human retinal imaging by Fourier domain optical coherence tomography," J. Biomed. Opt. 7, 457-463 (2002). 24. S. H. Yun, G. J. Tearney, B. E. Bouma, B. H. Park, and J. F. de Boer, "High-speed spectral-domain optical coherence tomography at 1.3 mu m wavelength," Opt. Express 11, 3598-3604 (2003). http://www.opticsexpress.org/abstract.cfm?URI=OPEX-11-26-3598. 25. "In vivo high-resolution video-rate spectral-domain optical coherence tomography of the human retina and optic nerve," Opt. Express 12, 367-376 (2004). http://www.opticsexpress.org/abstract.cfm?URI=OPEX-12-3-367.

David Gates - One of the best experts on this subject based on the ideXlab platform.

  • observation of a high performance Operating Regime with small edge localized modes in the national spherical torus experiment
    Nuclear Fusion, 2005
    Co-Authors: R Maingi, K Tritz, E D Fredrickson, J Menard, S A Sabbagh, D Stutman, M G Bell, R Bell, C E Bush, David Gates
    Abstract:

    We report the observation of a high performance scenario in the National Spherical Torus Experiment with very small edge-localized modes (ELMs). These ELMs, individually, have no measurable impact on the stored energy and are observed by several diagnostics. The small ELMs have clear differences as compared with the ELM types reported in the literature, and this Operating mode has distinct features compared with other high performance tokamak scenarios with little or no ELMs. The ELM is termed as 'type V', and it has a short-lived n = 1 magnetic precursor oscillation rotating counter to the plasma current and a distinct signature on the soft x-ray system. If we could extrapolate it, this scenario would provide an attractive Operating Regime for next step fusion experiments.

  • observation of a high performance Operating Regime with small edge localized modes in the national spherical torus experiment
    Other Information: PBD: 13 May 2004, 2004
    Co-Authors: R Maingi, K Tritz, E D Fredrickson, J Menard, S A Sabbagh, D Stutman, M G Bell, R Bell, C E Bush, David Gates
    Abstract:

    We report observation of a high performance scenario in the National Spherical Torus Experiment with very small edge-localized modes (ELMs). These ELMs have no measurable impact on stored energy and are consistent with high bootstrap current operation with line average density approaching Greenwald scaling. The ELM perturbation is observed to typically originate near the lower divertor region, as opposed to the outer midplane for ELMs described in the literature. If extrapolable, this scenario would provide an attractive Operating Regime for next step fusion experiments

Moustapha Mbaye - One of the best experts on this subject based on the ideXlab platform.

  • Geometric nonlinear dynamic analysis of uncertain structures with cyclic symmetry - Application to a mistuned industrial bladed disk
    2017
    Co-Authors: Evangéline Capiez-Lernout, Christian Soize, Moustapha Mbaye
    Abstract:

    This paper deals with the dynamical analysis of a mistuned industrial rotating integrally bladed disk, for which the Operating Regime under consideration takes into account the nonlinear geometrical effects induced by large displacements and deformations. First, a dedicated mean nonlinear reduced-order model of the tuned structure is explicitly constructed using the finite element method. The random nature of the mistuning is then modeled by using the nonparametric probabilistic approach extended to the nonlinear geometric context. The capability of the methodology to be applied to realistic industrial models is demonstrated through the paper. The dynamic analysis of the random response is then conducted in the frequency domain in order to quantify the impact of the nonlinear geometrical effects on the mistuned structure.

  • Computational nonlinear vibration analysis of uncertain mistuned bladed disks
    2017
    Co-Authors: Evangéline Capiez-Lernout, Christian Soize, Moustapha Mbaye
    Abstract:

    The recent improvements in turbomachinery design requires the analysis of exceptional Operating Regime of bladed disks corresponding to geometrical nonlinear effects induced by the large displacements/deformations. In addition, the random nature of the mistuning has also to be modeled. First, a mean nonlinear reduced-order model of the tuned bladed disk is explicitly constructed in the context of the finite element method. The investigation is then devoted to the modeling of the mistuning through the nonparametric probabilistic approach extended to the nonlinear geometric context. The stochastic nonlinear equations are solved in the time domain using the Monte Carlo numerical simulation coupled with advanced arc-length methods adapted to high nonlinear response levels. Finally, the methodology is applied through a numerical example of a bladed disk and a nonlinear analysis is performed in both time and frequency domain.

  • Nonlinear geometric analysis of a mistuned bladed disk
    2017
    Co-Authors: Evangéline Capiez-Lernout, Christian Soize, Moustapha Mbaye
    Abstract:

    This paper deals with the dynamical analysis and uncertainty quantification of a mistuned industrial rotating integrally bladed disk, for which the Operating Regime under consideration takes into account the nonlinear geometric effects induced by large displacements and deformations. First, a dedicated mean nonlinear reduced-order model of the tuned structure is explicitly constructed using three-dimensional solid finite elements. The random nature of the mistuning is then modeled by using the nonparametric probabilistic approach extended to the nonlinear geometric context. Such a computational strategy provides an efficient tool, which is applied to a computational model of an industrial centrifugal compressor with a large number of degrees of freedom. This allows for putting in evidence some new complex dynamical behaviors.

  • Mistuning analysis and uncertainty quantification of an industrial bladed disk with geometrical nonlinearity
    Journal of Sound and Vibration, 2017
    Co-Authors: Evangéline Capiez-Lernout, Christian Soize, Moustapha Mbaye
    Abstract:

    This paper deals with the dynamical analysis and uncertainty quantification of a mistuned industrial rotating integrally bladed disk, for which the Operating Regime under consideration takes into account the nonlinear geometrical effects induced by large displacements and deformations. First, a dedicated mean nonlinear reduced-order model of the tuned structure is explicitly constructed using the finite element method. The random nature of the mistuning is then modeled by using the nonparametric probabilistic approach extended to the nonlinear geometric context. Secondly, a detailed dynamic analysis and uncertainty propagation are conducted in order to quantify the impact of the nonlinear geometrical effects on the mistuned structure. The results show that the dynamic amplification in the frequency band is significant outside the frequency band of excitation due to the presence of geometric nonlinearities combined with mistuning effects.

R Maingi - One of the best experts on this subject based on the ideXlab platform.

  • observation of a high performance Operating Regime with small edge localized modes in the national spherical torus experiment
    Nuclear Fusion, 2005
    Co-Authors: R Maingi, K Tritz, E D Fredrickson, J Menard, S A Sabbagh, D Stutman, M G Bell, R Bell, C E Bush, David Gates
    Abstract:

    We report the observation of a high performance scenario in the National Spherical Torus Experiment with very small edge-localized modes (ELMs). These ELMs, individually, have no measurable impact on the stored energy and are observed by several diagnostics. The small ELMs have clear differences as compared with the ELM types reported in the literature, and this Operating mode has distinct features compared with other high performance tokamak scenarios with little or no ELMs. The ELM is termed as 'type V', and it has a short-lived n = 1 magnetic precursor oscillation rotating counter to the plasma current and a distinct signature on the soft x-ray system. If we could extrapolate it, this scenario would provide an attractive Operating Regime for next step fusion experiments.

  • observation of a high performance Operating Regime with small edge localized modes in the national spherical torus experiment
    Other Information: PBD: 13 May 2004, 2004
    Co-Authors: R Maingi, K Tritz, E D Fredrickson, J Menard, S A Sabbagh, D Stutman, M G Bell, R Bell, C E Bush, David Gates
    Abstract:

    We report observation of a high performance scenario in the National Spherical Torus Experiment with very small edge-localized modes (ELMs). These ELMs have no measurable impact on stored energy and are consistent with high bootstrap current operation with line average density approaching Greenwald scaling. The ELM perturbation is observed to typically originate near the lower divertor region, as opposed to the outer midplane for ELMs described in the literature. If extrapolable, this scenario would provide an attractive Operating Regime for next step fusion experiments