Fourier domain mode locked (FDML) Laser

Research and development of the fastest tunable Lasers

In Fourier Domain Mode Locking (FDML), complementary to standard mode-locked lasers, not the phase or amplitude but the spectrum is modulated. This creates a sequence of spectrally very pure optical frequency sweeps, which in principle can also be compressed into a train of ultrashort light pulses. The optical signal of a complete frequency sweep is optically stored in the resonator.

FDML lasers have just revolutionized biomedical imaging using OCT in terms of imaging speed. They are also used in spectroscopy, to generate high-frequency microwave frequency sweeps, and for fast laser scanning units, among other applications. Although commercial FDML lasers are already available, the mechanism of FDML and potential problems that may arise are still partially misunderstood. The goal of this research topic is to develop a comprehensive theoretical understanding of FDML, delineate the experimental limitations and problems and explore potential applications in biomedical imaging and spectroscopy.

Objectives:

  • Laser Physics - Investigate the relevant physical effects and operation of real FDML laser implementations to develop a comprehensive understanding and validated theoretical model.
  • Technology - Further development of existing and novel operating modes of FDML lasers with a focus on practical applications.
  • Application - Define and implement FDML lasers on new applications in metrology, spectroscopy, and imaging.

Publications

2007

Robert Huber, Vivek J. Srinivasan, Desmond C. Adler, Iwona Gorczynska, and James G. Fujimoto,
Fourier Domain Mode Locking (FDML) in the non-zero dispersion regime: A laser for ultrahigh-speed retinal OCT imaging at 236kHz line rate, in Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference and Photonic Applications Systems Technologies , Optica Publishing Group, 052007. pp. CThAA5.
DOI:10.1109/CLEO.2007.4452681}
Bibtex: BibTeX
@inproceedings{Huber:07,
author = {Robert Huber and Vivek J. Srinivasan and Desmond C. Adler and I. Gorczynska and James G. Fujimoto},
booktitle = {Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference and Photonic Applications Systems Technologies},
journal = {Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference and Photonic Applications Systems Technologies},
keywords = {General physics; General science; Fourier domain mode locking; Image quality; In vivo imaging; Laser sources; Ophthalmic imaging; Optical coherence tomography},
pages = {CThAA5},
publisher = {Optica Publishing Group},
title = {Fourier Domain Mode Locking (FDML) in the non-zero dispersion regime: A laser for ultrahigh-speed retinal OCT imaging at 236kHz line rate},
year = {2007},
url = {https://opg.optica.org/abstract.cfm?URI=CLEO-2007-CThAA5},
abstract = {Fourier Domain Mode Locking (FDML) in the 1070nm wavelength range is investigated. Problems, design rules and the performance of an FDML laser with a dispersive cavity are discussed. Retinal OCT imaging at 236kHz is demonstrated.},
}
Michael W. Jenkins, Desmond C. Adler, Madhusudhana Gargesha, Robert Huber, Florence Rothenberg, Jon Belding, Masahiro Watanabe, David L. Wilson, James G. Fujimoto, and Andrew M. Rollins,
Ultrahigh-speed optical coherence tomography imaging and visualization of the embryonic avian heart using a buffered Fourier Domain Mode Locked laser, Opt. Express , vol. 15, no. 10, pp. 6251-6267, 05 2007. Optica Publishing Group.
DOI:10.1364/OE.15.006251
Bibtex: BibTeX
@article{Jenkins:07,
author = {M. W. Jenkins and D. C. Adler and M. Gargesha and R. Huber and F. Rothenberg and J. Belding and M. Watanabe and D. L. Wilson and J. G. Fujimoto and A. M. Rollins},
journal = {Opt. Express},
keywords = {Three-dimensional image processing; Lasers; Medical and biological imaging; Optical coherence tomography; Developmental biology; Gated imaging; Imaging systems; Laser Doppler velocimetry; Laser modes; Mode locking},
number = {10},
pages = {6251--6267},
publisher = {Optica Publishing Group},
title = {Ultrahigh-speed optical coherence tomography imaging and visualization of the embryonic avian heart using a buffered Fourier Domain Mode Locked laser},
volume = {15},
month = {May},
year = {2007},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-15-10-6251},
doi = {10.1364/OE.15.006251},
abstract = {The embryonic avian heart is an important model for studying cardiac developmental biology. The mechanisms that govern the development of a four-chambered heart from a peristaltic heart tube are largely unknown due in part to a lack of adequate imaging technology. Due to the small size and rapid motion of the living embryonic avian heart, an imaging system with high spatial and temporal resolution is required to study these models. Here, an optical coherence tomography (OCT) system using a buffered Fourier Domain Mode Locked (FDML) laser is applied for ultrahigh-speed non-invasive imaging of embryonic quail hearts at 100,000 axial scans per second. The high scan rate enables the acquisition of high temporal resolution 2D datasets (195 frames per second or 5.12 ms between frames) and 3D datasets (10 volumes per second). Spatio-temporal details of cardiac motion not resolvable using previous OCT technology are analyzed. Visualization and measurement techniques are developed to non-invasively observe and quantify cardiac motion throughout the brief period of systole (less than 50 msec) and diastole. This marks the first time that the preseptated embryonic avian heart has been imaged in 4D without the aid of gating and the first time it has been viewed in cross section during looping with extremely high temporal resolution, enabling the observation of morphological dynamics of the beating heart during systole.},
}
Shu-Wei Huang, Aaron D Aguirre, Robert Huber, Desmond C. Adler, and James G. Fujimoto,
Swept source optical coherence microscopy using a Fourier domain mode-locked laser, Opt. Express , vol. 15, no. 10, pp. 6210-6217, 05 2007. Optica Publishing Group.
DOI:10.1364/OE.15.006210
Bibtex: BibTeX
@article{Huang:07,
author = {Shu-Wei Huang and Aaron D. Aguirre and Robert A. Huber and Desmond C. Adler and James G. Fujimoto},
journal = {Opt. Express},
keywords = {Optical coherence tomography; Lasers, tunable; Medical and biological imaging; Confocal microscopy; Three-dimensional microscopy; Image quality; Laser sources; Mode locking; Optical delay lines; Swept sources; Three dimensional imaging},
number = {10},
pages = {6210--6217},
publisher = {Optica Publishing Group},
title = {Swept source optical coherence microscopy using a Fourier domain mode-locked laser},
volume = {15},
month = {May},
year = {2007},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-15-10-6210},
doi = {10.1364/OE.15.006210},
abstract = {Swept source optical coherence microscopy (OCM) enables cellular resolution en face imaging as well as integration with optical coherence tomography (OCT) cross sectional imaging. A buffered Fourier domain mode-locked (FDML) laser light source provides high speed, three dimensional imaging. Image resolutions of 1.6 $\mu$m {\texttimes} 8 $\mu$m (transverse {\texttimes} axial) with a 220 $\mu$m {\texttimes} 220 $\mu$m field of view and sensitivity higher than 98 dB are achieved. Three dimensional cellular imaging is demonstrated in vivo in the Xenopus laevis tadpole and ex vivo in the rat kidney and human colon.},
}
Desmond C. Adler, Robert Huber, and James G. Fujimoto,
Phase-sensitive optical coherence tomography at up to 370,000 lines per second using buffered Fourier domain mode-locked lasers, Opt. Lett. , vol. 32, no. 6, pp. 626-628, 03 2007. Optica Publishing Group.
DOI:10.1364/OL.32.000626
Bibtex: BibTeX
@article{Adler:07,
author = {Desmond C. Adler and Robert Huber and James G. Fujimoto},
journal = {Opt. Lett.},
keywords = {Optical coherence tomography; Phase measurement; Lasers, tunable; Amplified spontaneous emission; Laser sources; Mode locking; Optical coherence tomography; Phase measurement; Swept lasers},
number = {6},
pages = {626--628},
publisher = {Optica Publishing Group},
title = {Phase-sensitive optical coherence tomography at up to 370,000 lines per second using buffered Fourier domain mode-locked lasers},
volume = {32},
month = {Mar},
year = {2007},
url = {https://opg.optica.org/ol/abstract.cfm?URI=ol-32-6-626},
doi = {10.1364/OL.32.000626},
abstract = {Buffered Fourier domain mode-locked (FDML) lasers are demonstrated for dynamic phase-sensitive optical coherence tomography (OCT) and 3D OCT phase microscopy. Systems are operated at sweep speeds of 42, 117, and 370 kHz, and displacement sensitivities of 39, 52, and 102 pm are achieved, respectively. Sensitivities are comparable to spectrometer-based OCT phase microscopy systems, but much faster acquisition speeds are possible. An additional factor of sqrt 2 improvement in noise performance is observed for differential phase measurements, which is important for Doppler OCT. Dynamic measurements of piezoelectric transducer motion and static 3D OCT phase microscopy are demonstrated. Buffered FDML lasers provide excellent displacement sensitivities at extremely high sweep speeds.},
}
Robert Huber, Desmond C. Adler, Vivek J. Srinivasan, Iwona Gorczynska, and James G. Fujimoto,
Fourier domain mode-locked (FDML) lasers at 1050 nm and 202,000 sweeps per second for OCT retinal imaging, in Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine XI , James G. Fujimoto and Joseph A. Izatt and Valery V. Tuchin, Eds. SPIE, 022007. pp. 642907.
DOI:10.1117/12.704084
Bibtex: BibTeX
@inproceedings{10.1117/12.704084,
author = {Robert A. Huber and Desmond C. Adler and Vivek J. Srinivasan and Iwona M Gorczynska and James G. Fujimoto},
title = {{Fourier domain mode-locked (FDML) lasers at 1050 nm and 202,000 sweeps per second for OCT retinal imaging}},
volume = {6429},
booktitle = {Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine XI},
editor = {James G. Fujimoto and Joseph A. Izatt and Valery V. Tuchin},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {642907},
abstract = {Retinal imaging ranks amongst the most important clinical applications for optical coherence
tomography (OCT) [1, 2]. The recent demonstration of increased sensitivity [3-6] in Fourier
Domain detection [7, 8] has opened the way for dramatically higher imaging speeds, up to axial
scan rates of several tens of kilohertz. However, these imaging speeds are still not sufficient for
high density 3D datasets and a further increase to several hundreds of kilohertz is necessary. In
this paper we demonstrate a swept laser source at 1050 nm with a sweep rate of 202 kHz. The
laser source provides ~10 mW average output power, up to 60 nm total sweep range and a
sensitivity roll off of less than 10 dB over 4 mm. In vivo 2D and 3D imaging of the human retina
at a record axial scan rate of 101 kHz is demonstrated. These results suggest that swept source
OCT has the potential to significantly outperform spectral/Fourier domain OCT for ophthalmic
imaging applications in the future.},
keywords = {tunable laser, optical coherence tomography, Fourier domain mode locking, swept source, OCT, FDML, retinal imaging, ophthalmic imaging},
year = {2007},
doi = {10.1117/12.704084},
URL = {https://doi.org/10.1117/12.704084}
}
Desmond C. Adler, Robert Huber, and James G. Fujimoto,
Phase-sensitive optical coherence tomography using buffered Fourier domain mode-locked lasers at up to 370,000 scans per second, in Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine XI , James G. Fujimoto and Joseph A. Izatt and Valery V. Tuchin, Eds. SPIE, 022007. pp. 64291L.
DOI:10.1117/12.704128
Bibtex: BibTeX
@inproceedings{10.1117/12.704128,
author = {Desmond C. Adler and Robert Huber and James G. Fujimoto},
title = {{Phase-sensitive optical coherence tomography using buffered Fourier domain mode-locked lasers at up to 370,000 scans per second}},
volume = {6429},
booktitle = {Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine XI},
editor = {James G. Fujimoto and Joseph A. Izatt and Valery V. Tuchin},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {64291L},
abstract = {Phase sensitive optical coherence tomography (OCT) can be used to obtain sub-nanometer
displacement measurements of biological and non-biological samples. This technique has many
applications, including detection of small amplitude surface motion, and high axial resolution OCT
phase microscopy. Doppler OCT is another type of phase sensitive imaging, where differential
phase measurements are used to detect fluid flow in biological specimens. For all types of phase
sensitive OCT, a light source with low phase noise is required in order to provide good
displacement sensitivity. High speed imaging is also necessary in order to minimize motion artifacts
and enable the detection of fast transient events. In this manuscript, buffered Fourier Domain Mode
Locked (FDML) lasers are demonstrated for ultrahigh-speed phase sensitive OCT detection. The
lasers are operated at sweep speeds of 42, 117, and 370 kHz, and displacement sensitivities of 39,
52, and 102 pm are achieved, respectively. These displacement sensitivities are comparable to
spectrometer-based phase sensitive OCT systems, but acquisition speeds 1.4 - 13x faster are
possible using buffered FDML lasers. An additional factor of √2 improvement in noise performance
is observed for differential phase measurements, which has important implications for Doppler
OCT. Dynamic measurements of rapid, small-amplitude piezoelectric transducer motion are
demonstrated. In general, buffered FDML lasers provide excellent displacement sensitivities at
extremely high sweep speeds for phase sensitive OCT measurements.},
keywords = {optical coherence tomography, OCT, optical coherence phase microscopy, swept source phase microscopy, doppler optical coherence tomography, frequency swept lasers, Fourier Domain Mode Locked lasers, FDML},
year = {2007},
doi = {10.1117/12.704128},
URL = {https://doi.org/10.1117/12.704128}
}
Vivek J. Srinivasan, Robert Huber, Iwona Gorczynska, James G. Fujimoto, James Jiang, Peter Reisen, and Alex E. Cable,
High-speed, high-resolution optical coherence tomography retinal imaging with a frequency-swept laser at 850 nm, Opt. Lett. , vol. 32, no. 4, pp. 361-363, 02 2007. Optica Publishing Group.
DOI:10.1364/OL.32.000361
Bibtex: BibTeX
@article{Srinivasan:07,
author = {V. J. Srinivasan and R. Huber and I. Gorczynska and J. G. Fujimoto and J. Y. Jiang and P. Reisen and A. E. Cable},
journal = {Opt. Lett.},
keywords = {Optical coherence tomography; Lasers, tunable; Medical and biological imaging; Optical coherence tomography; Retina scanning; Semiconductor lasers; Semiconductor optical amplifiers; Spontaneous emission; Tunable lasers},
number = {4},
pages = {361--363},
publisher = {Optica Publishing Group},
title = {High-speed, high-resolution optical coherence tomography retinal imaging with a frequency-swept laser at 850 nm},
volume = {32},
month = {Feb},
year = {2007},
url = {https://opg.optica.org/ol/abstract.cfm?URI=ol-32-4-361},
doi = {10.1364/OL.32.000361},
abstract = {High-speed, high-resolution optical coherence tomography (OCT) imaging of the human retina is demonstrated using a frequency-swept laser at 850 nm. A compact external cavity semiconductor laser design, optimized for swept-source ophthalmic OCT, is described. The laser enables an effective 16 kHz sweep rate with \>10 mm coherence length and a tuning range of $\sim$35 nm full width at half-maximum, yielding an axial resolution of \<7 $\mu$m in tissue.},
}
Laura A. Kranendonk, Robert Huber, James G. Fujimoto, and Scott T. Sanders,
Wavelength-agile H2O absorption spectrometer for thermometry of general combustion gases, Proceedings of the Combustion Institute , vol. 31, no. 1, pp. 783-790, 01 2007.
DOI:10.1016/j.proci.2006.08.003
Bibtex: BibTeX
@article{KRANENDONK2007783,
title = {Wavelength-agile H2O absorption spectrometer for thermometry of general combustion gases},
journal = {Proceedings of the Combustion Institute},
volume = {31},
number = {1},
pages = {783-790},
year = {2007},
issn = {1540-7489},
doi = {https://doi.org/10.1016/j.proci.2006.08.003},
url = {https://www.sciencedirect.com/science/article/pii/S1540748906002665},
author = {Laura A. Kranendonk and Robert Huber and James G. Fujimoto and Scott T. Sanders},
keywords = {Thermometry, Wavelength-agile, Absorption spectroscopy},
abstract = {Using a novel Fourier-domain mode-locking (FDML) laser scanning 1330–1380nm, we have developed a gas thermometer based on absorption spectroscopy that is appropriate for combustion gases at essentially arbitrary conditions. The path-integrated measurements are particularly useful in homogeneous environments, and here we present measurements in a controlled piston engine and a shock tube. Engine measurements demonstrate a RMS temperature precision of ±3% at 1500K and 200kHz bandwidth; the precision is improved dramatically by averaging. Initial shock tube measurements place the absolute accuracy of the thermometer within ∼2% to 1000K. The sensor performs best when significant H2O vapor is present, but requires only XH2OL>0.07cm at 300K, XH2OL>0.25cm at 1000K, or XH2OL>1.25cm at 3000K for 2% accurate thermometry, assuming a 4kHz measurement bandwidth (200kHz scans with 50 averages). The sensor also provides H2O mole fraction and shows potential for monitoring gas pressure based on the broadening of spectral features. To aid in designing other sensors based on high-temperature, high-pressure H2O absorption spectroscopy, a database of measured spectra is included.}
}

2006

Robert Huber, Desmond C. Adler, and James G. Fujimoto,
Buffered Fourier domain mode locking: unidirectional swept laser sources for optical coherence tomography imaging at 370,000 lines/s, Opt. Lett. , vol. 31, no. 20, pp. 2975-2977, Oct. 2006. Optica Publishing Group.
DOI:10.1364/OL.31.002975
Bibtex: BibTeX
@article{Huber:06,
author = {Robert Huber and Desmond C. Adler and James G. Fujimoto},
journal = {Opt. Lett.},
keywords = {Optical coherence tomography; Lasers, tunable; Amplified spontaneous emission; Fourier domain mode locking; Image quality; Laser sources; Optical coherence tomography; Swept sources},
number = {20},
pages = {2975--2977},
publisher = {Optica Publishing Group},
title = {Buffered Fourier domain mode locking: unidirectional swept laser sources for optical coherence tomography imaging at 370,000 lines/s},
volume = {31},
month = {Oct},
year = {2006},
url = {https://opg.optica.org/ol/abstract.cfm?URI=ol-31-20-2975},
doi = {10.1364/OL.31.002975},
abstract = {We describe buffered Fourier domain mode locking (FDML), a technique for tailoring the output and multiplying the sweep rate of FDML lasers. Buffered FDML can be used to create unidirectional wavelength sweeps from the normal bidirectional sweeps in an FDML laser without sacrificing sweep rate. We also investigate the role of the laser source in dynamic range versus sensitivity performance in optical coherence tomography (OCT) imaging. Unidirectional sweep rates of 370 kHz over a 100 nm range at a center wavelength of 1300 nm are achieved. High-speed, swept-source OCT is demonstrated at record speeds of up to 370,000 axial scans per second.},
}
Robert Huber, Maciej Wojtkowski, and James G. Fujimoto,
Fourier domain mode locking (FDML): Three-dimensional OCT imaging at 906 frames per second, in 2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference , IEEE, 052006. pp. 1-2.
DOI:10.1109/CLEO.2006.4627914
Bibtex: BibTeX
@INPROCEEDINGS{4627914,
  author={Huber, R. and Wojtkowski, M. and Fujimoto, J. G.},
  booktitle={2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference}, 
  title={Fourier Domain Mode Locking (FDML): Three-dimensional OCT imaging at 906 frames per second}, 
  year={2006},
  volume={},
  number={},
  pages={1-2},
  abstract={Fourier domain mode locking is a new operation regime of lasers. Highly chirped frequency swept waveforms rather than short pulses are generated. The mechanism and its application for ultrahigh-speed biomedical OCT imaging are discussed.},
  keywords={},
  doi={10.1109/CLEO.2006.4627914},
  ISSN={2160-9004},
  month={May},}
Robert Huber, Maciej Wojtkowski, and James G. Fujimoto,
Fourier Domain Mode Locking (FDML): A new laser operating regime and applications for optical coherence tomography, Optics Express , vol. 14, no. 8, pp. 3225 - 3237, 04 2006.
DOI:10.1364/OE.14.003225
Bibtex: BibTeX
@article{Huber:06,
author = {R. Huber and M. Wojtkowski and J. G. Fujimoto},
journal = {Opt. Express},
keywords = {Optical coherence tomography; Lasers, tunable; Frequency modulated lasers; Full field optical coherence tomography; Laser operation; Light fields; Medical imaging; Mode locking},
number = {8},
pages = {3225--3237},
publisher = {Optica Publishing Group},
title = {Fourier Domain Mode Locking (FDML): A new laser operating regime and applications for optical coherence tomography},
volume = {14},
month = {Apr},
year = {2006},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-14-8-3225},
doi = {10.1364/OE.14.003225},
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{\texttimes}128{\texttimes}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.},
}
Laura A. Kranendonk, Joachim W. Walewski, Scott T. Sanders, and Robert Huber,
"Measurements of Gas Temperature in a HCCI Engine Using a Fourier Domain Mode Locking Laser" SAE Technical Paper 2006-01-1366, 04 2006.
DOI:10.4271/2006-01-1366
Bibtex: BibTeX
@TechReport{HU_2006_Kranendonk_a,
  Title                    = {{Measurements of Gas Temperature in a HCCI Engine Using a Fourier Domain Mode Locking Laser}},
  Author                   = {Kranendonk, Laura A and Walewski, Joachim W and Sanders, Scott T and Huber, Robert and Fujimoto, James G},
  Year                     = {2006},
  Month                    = apr,
  pages  = {1366 1--5},
  Doi                      = {10.4271/2006-01-1366},
keywords = {AG-Huber_FDML, AG-Huber_OCT},
  Url                      = {http://www.sae.org/technical/papers/2006-01-1366}
}
Kenji Taira, Robert Huber, Maciej Wojtkowski, and James G. Fujimoto,
Fourier domain mode-locked lasers for swept source OCT imaging at up to 290 kHz scan rates, in Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine X , Valery V. Tuchin and Joseph A. Izatt and James G. Fujimoto, Eds. SPIE, 022006. pp. 60790U.
DOI:10.1117/12.648880
Bibtex: BibTeX
@inproceedings{10.1117/12.648880,
author = {R. Huber and K. Taira and M. Wojtkowski and J. G. Fujimoto},
title = {{Fourier domain mode-locked lasers for swept source OCT imaging at up to 290 kHz scan rates}},
volume = {6079},
booktitle = {Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine X},
editor = {Valery V. Tuchin and Joseph A. Izatt and James G. Fujimoto},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {60790U},
abstract = {A new type of laser operation, Fourier Domain Mode Locking (FDML), is demonstrated for high performance, frequency swept light sources.  FDML achieves superior sweep speeds, coherence lengths and bandwidths compared to standard bulk or fiber lasers.  At 1300 nm a sweep range up to 145 nm, up to 4 cm delay length, and sweep rates up to 290 kHz were achieved.  This light source is demonstrated for swept source OCT imaging.},
keywords = {Fourier Domain Mode Locking, swept laser, tunable laser, wavelength agile, optical coherence tomography, spectral domain, Fourier domain, fiber laser},
year = {2006},
doi = {10.1117/12.648880},
URL = {https://doi.org/10.1117/12.648880}
}
Laura A. Kranendonk, Joachim W. Walewski, Scott T. Sanders, Robert Huber, and James G. Fujimoto,
Measurements of Gas Temperature in an HCCI Engine by Use of a Fourier-Domain Mode-Locking Laser, in Laser Applilcations to Chemical, Security and Environmental Analysis , Optica Publishing Group, 022006. pp. TuB2.
DOI:10.1364/LACSEA.2006.TuB2
Bibtex: BibTeX
@inproceedings{Kranendonk:06,
author = {Laura A. Kranendonk and Joachim W. Walewski and Scott T. Sanders and Robert Huber and James G. Fujimoto},
booktitle = {Laser Applilcations to Chemical, Security and Environmental Analysis},
journal = {Laser Applilcations to Chemical, Security and Environmental Analysis},
keywords = {Lasers and laser optics; Diode lasers; Lasers, tunable; Laser operation; Laser sensors; Lasers; Mode locking; Spontaneous emission; Tunable diode lasers},
pages = {TuB2},
publisher = {Optica Publishing Group},
title = {Measurements of gas temperature in an HCCI engine by use of a Fourier-domain mode-locking laser},
year = {2006},
url = {https://opg.optica.org/abstract.cfm?URI=LACSEA-2006-TuB2},
doi = {10.1364/LACSEA.2006.TuB2},
abstract = {Initial measurements of water vapor temperature by use of a Fourier-domain mode-locking laser were performed in a homogenous charge compression ignition engine. We assessed the potential of this FDML laser in combustion applications.},
}

2005

Robert Huber, Maciej Wojtkowski, James G. Fujimoto, James Jiang, and Alex E. Cable,
Three-dimensional and C-mode OCT imaging with a compact, frequency swept laser source at 1300 nm, Opt. Express , vol. 13, no. 26, pp. 10523-10538, Dec. 2005. Optica Publishing Group.
DOI:10.1364/OPEX.13.010523
Bibtex: BibTeX
@article{Huber:05,
author = {R. Huber and M. Wojtkowski and J. G. Fujimoto and J. Y. Jiang and A. E. Cable},
journal = {Opt. Express},
keywords = {Optical coherence tomography; Lasers, tunable; High speed imaging; Image fusion; Laser sources; Semiconductor lasers; Swept lasers; Three dimensional imaging},
number = {26},
pages = {10523--10538},
publisher = {Optica Publishing Group},
title = {Three-dimensional and C-mode OCT imaging with a compact, frequency swept laser source at 1300 nm},
volume = {13},
month = {Dec},
year = {2005},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-13-26-10523},
doi = {10.1364/OPEX.13.010523},
abstract = {We demonstrate high resolution, three-dimensional OCT imaging with a high speed, frequency swept 1300 nm laser source. A new external cavity semiconductor laser design, optimized for application to swept source OCT, is discussed. The design of the laser enables adjustment of an internal spectral filter to change the filter bandwidth and provides a robust bulk optics design. The laser generates ~30 mW instantaneous peak power at an effective 16 kHz sweep rate with a tuning range of ~133 nm full width. In frequency domain reflectometry and OCT applications, 109 dB sensitivity and ~10 $\mu$m axial resolution in tissue can be achieved with the swept laser. The high imaging speeds enable three-dimensional OCT imaging, including zone focusing or C-mode imaging and image fusion to acquire large depth of field data sets with high resolution. In addition, three-dimensional OCT data provides coherence gated en face images similar to optical coherence microscopy (OCM) and also enables the generation of images similar to confocal microscopy by summing signals in the axial direction. High speed, three-dimensional OCT imaging can provide comprehensive data which combines the advantages of optical coherence tomography and microscopy in a single system.},
}
Robert Huber, Kenji Taira, Maciej Wojtkowski, and James G. Fujimoto,
Fourier domain mode locked lasers for OCT imaging at up to 290 kHz sweep rates, in Optical Coherence Tomography and Coherence Techniques II , Wolfgang Drexler, Eds. SPIE, Oct.2005. pp. 58611B.
DOI:10.1117/12.641732
Bibtex: BibTeX
@inproceedings{10.1117/12.641732,
author = {R. Huber and K. Taira and M. Wojtkowski and J. G. Fujimoto},
title = {{Fourier domain mode locked lasers for OCT imaging at up to 290 kHz sweep rates}},
volume = {5861},
booktitle = {Optical Coherence Tomography and Coherence Techniques II},
editor = {Wolfgang Drexler},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {58611B},
abstract = {A high speed, tunable laser using Fourier Domain Mode Locking is demonstrated for OCT imaging.  Record sweep speeds up to 290 kHz, 3 cm coherence length and 145 nm range at 1300 nm are achieved.},
keywords = {Fourier domain mode locking, swept source, swept laser, tunable laser, wavelength agile laser, optical coherence tomography, spectral OCT, Fourier domain},
year = {2005},
doi = {10.1117/12.641732},
URL = {https://doi.org/10.1117/12.641732}
}
Robert Huber, Kenji Taira, and James G. Fujimoto,
Fourier Domain Mode Locking: Overcoming limitations of frequency swept light sources and pulsed lasers, in Conference on Lasers and Electro-Optics Europe/ European Quantum Electronics Conference (CLEO/Europe - EQEC 2005) , 052005. pp. CP3-5-THU.
Bibtex: BibTeX
@InProceedings{HU_2005_Huber_a,
  Title                    = {{Fourier Domain Mode Locking: Overcoming limitations of frequency swept light sources and pulsed lasers}},
  Author                   = {Huber, Robert A and Taira, Kenji and Fujimoto, James G},
  Booktitle                = {Conference on Lasers and Electro-Optics Europe/ European Quantum Electronics Conference (CLEO/Europe - EQEC 2005)},
keywords = {AG-Huber_FDML, AG-Huber_OCT},
  Year                     = { 2005}
}
Robert Huber, Kenji Taira, Tony H. Ko, Maciej Wojtkowski, Vivek J. Srinivasan, James G. Fujimoto, and Kevin Hsu,
High-Speed, Amplified, Frequency Swept Laser at 20 kHz Sweep Rates for OCT Imaging - Technical Digest (CD), in Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science and Photonic Applications Systems Technologies , Optica Publishing Group, 052005. pp. JThE33.
DOI:10.1109/QELS.2005.1549239
Bibtex: BibTeX
@inproceedings{Huber:05,
author = {R. Huber and K. Taira and T. H. Ko and M. Wojtkowski and V. Srinivasan and J. G. Fujimoto and K. Hsu},
booktitle = {Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science and Photonic Applications Systems Technologies},
journal = {Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science and Photonic Applications Systems Technologies},
keywords = {Imaging systems; Optical coherence tomography; Lasers and laser optics; Lasers, tunable; Laser amplifiers; Laser sources; Light sources; Optical coherence tomography; Point spread function; Ring lasers},
pages = {JThE33},
publisher = {Optica Publishing Group},
title = {High-speed, amplified, frequency swept laser at 20 kHz sweep rates for OCT imaging},
year = {2005},
url = {https://opg.optica.org/abstract.cfm?URI=QELS-2005-JThE33},
abstract = {We demonstrate a high-speed, frequency swept, 1300 nm laser for Fourier domain OCT. The laser generates ~45 mW instantaneous power with 20 kHz sweep rates and achieves 108 dB sensitivity and 12.7 um resolution.},
}
Robert Huber, Maciej Wojtkowski, Kenji Taira, James G. Fujimoto, and Kevin Hsu,
Amplified, frequency swept lasers for frequency domain reflectometry and OCT imaging: design and scaling principles, Opt. Express , vol. 13, no. 9, pp. 3513-3528, 05 2005. Optica Publishing Group.
DOI:10.1364/OPEX.13.003513
Bibtex: BibTeX
@article{Huber:05,
author = {R. Huber and M. Wojtkowski and K. Taira and J. G. Fujimoto and K. Hsu},
journal = {Opt. Express},
keywords = {Optical coherence tomography; Lasers, tunable; Fiber lasers; Fiber optic amplifiers; Fiber optic components; Laser sources; Light sources; Tunable diode lasers},
number = {9},
pages = {3513--3528},
publisher = {Optica Publishing Group},
title = {Amplified, frequency swept lasers for frequency domain reflectometry and OCT imaging: design and scaling principles},
volume = {13},
month = {May},
year = {2005},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-13-9-3513},
doi = {10.1364/OPEX.13.003513},
abstract = {We demonstrate a high-speed, frequency swept, 1300 nm laser source for frequency domain reflectometry and OCT with Fourier domain/swept-source detection. The laser uses a fiber coupled, semiconductor amplifier and a tunable fiber Fabry-Perot filter. We present scaling principles which predict the maximum frequency sweep speed and trade offs in output power, noise and instantaneous linewidth performance. The use of an amplification stage for increasing output power and for spectral shaping is discussed in detail. The laser generates ~45 mW instantaneous peak power at 20 kHz sweep rates with a tuning range of ~120 nm full width. In frequency domain reflectometry and OCT applications the frequency swept laser achieves 108 dB sensitivity and ~10 {\textmu}m axial resolution in tissue. We also present a fast algorithm for real time calibration of the fringe signal to equally spaced sampling in frequency for high speed OCT image preview.},
}
Robert Huber, Kenji Taira, Maciej Wojtkowski, Tony H. Ko, James G. Fujimoto, and Kevin Hsu,
Figh-speed frequency swept light source for Fourier domain OCT at 20 kHz A-scan rate, in Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine IX , Valery V. Tuchin and Joseph A. Izatt and James G. Fujimoto, Eds. SPIE, 042005. pp. 96-100.
DOI:10.1117/12.592552
Bibtex: BibTeX
@inproceedings{10.1117/12.592552,
author = {Robert Huber and Kenji Taira and Maciej Wojtkowski and Tony Hong-Tyng Ko and James G. Fujimoto and Kevin Hsu},
title = {{High-speed-frequency swept light source for Fourier domain OCT at 20-kHz A-scan rate}},
volume = {5690},
booktitle = {Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine IX},
editor = {Valery V. Tuchin and Joseph A. Izatt and James G. Fujimoto},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {96 -- 100},
abstract = {We demonstrate a high-speed tunable, continuous wave laser source for Fourier domain OCT.  The laser source is based on a fiber coupled, semiconductor optical amplifier and a tunable ultrahigh finesse, fiber Fabry Perot filter for frequency tuning.  The light source provides frequency scan rates of up to 20,000 sweeps per second over a wavelength range of >70 nm FWHM at 1330 nm, yielding an axial resolution of ~14 μm in air.  The linewidth is narrow and corresponds to a coherence length of several mm, enabling OCT imaging over a large axial range.},
keywords = {swept source, Fourier Domain, OCT, tunable laser, Spectral Domain, frequency domain imaging, OFDI, sweep},
year = {2005},
doi = {10.1117/12.592552},
URL = {https://doi.org/10.1117/12.592552}
}