@article{Todor:11,
author = {Sebastian Todor and Benjamin Biedermann and Wolfgang Wieser and Robert Huber and Christian Jirauschek},
journal = {Opt. Express},
keywords = {Laser theory; Lasers, tunable; Optical coherence tomography; Linewidth; Laser sources; Mode locking; Power spectra; Semiconductor lasers; Swept lasers; Tunable lasers},
number = {9},
pages = {8802--8807},
publisher = {Optica Publishing Group},
title = {Instantaneous lineshape analysis of Fourier domain mode-locked lasers},
volume = {19},
month = {Apr},
year = {2011},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-19-9-8802},
doi = {10.1364/OE.19.008802},
abstract = {We present a theoretical and experimental analysis of the instantaneous lineshape of Fourier domain mode-locked (FDML) lasers, yielding good agreement. The simulations are performed employing a recently introduced model for FDML operation. Linewidths around 10 GHz are found, which is significantly below the sweep filter bandwidth. The effect of detuning between the sweep filter drive frequency and cavity roundtrip time is studied revealing features that cannot be resolved in the experiment, and shifting of the instantaneous power spectrum against the sweep filter center frequency is analyzed. We show that, in contrast to most other semiconductor based lasers, the instantaneous linewidth is governed neither by external noise sources nor by amplified spontaneous emission, but it is directly determined by the complex FDML dynamics.},
}

@inproceedings{10.1117/12.875594,
author = {Cedric Blatter and Branislav Grajciar and Robert Huber and Rainer A. Leitgeb},
title = {{Structural and functional imaging with extended focus dark-field OCT at 1300nm}},
volume = {7889},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XV},
editor = {James G. Fujimoto and Joseph A. Izatt and Valery V. Tuchin},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {78891D},
abstract = {We present an extended focus FDOCT setup with FDML swept source centered at 1310nm. The illumination, preserving
its lateral extend over a large depth range thanks to the use of a Bessel beam, is decoupled from the Gaussian detection in
order to increase the global sensitivity. The efficient spatial separation enables dark-field imaging. In-vivo measurements
in the skin were performed to demonstrate the gain in lateral resolution while preserving the imaging depth. More, the
calculation of the speckle variance between B-Scans allows a clear visualization of the microvasculature.},
keywords = {Extended focus, Dark Field imaging, Bessel beam, FDML Swept Source, dermatology, microvascularisation imaging},
year = {2011},
doi = {10.1117/12.875594},
URL = {https://doi.org/10.1117/12.875594}
}

@article{Klein:11,
author = {Thomas Klein and Wolfgang Wieser and Christoph M. Eigenwillig and Benjamin R. Biedermann and Robert Huber},
journal = {Opt. Express},
keywords = {Optical coherence tomography; Lasers, tunable; Imaging systems; Ophthalmology; Optical coherence tomography; Retina scanning ; Fiber lasers; Image processing; Image quality; Mode locking; Ophthalmic imaging; Three dimensional imaging},
number = {4},
pages = {3044--3062},
publisher = {Optica Publishing Group},
title = {Megahertz OCT for ultrawide-field retinal imaging with a 1050nm Fourier domain mode-locked laser},
volume = {19},
month = {Feb},
year = {2011},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-19-4-3044},
doi = {10.1364/OE.19.003044},
abstract = {We demonstrate ultrahigh speed swept source retinal OCT imaging using a Fourier domain mode locked (FDML) laser. The laser uses a combination of a semiconductor optical amplifier and an ytterbium doped fiber amplifier to provide more than 50mW output power. The 1050nm FDML laser uses standard telecom fiber for the km long delay line instead of two orders of magnitude more expensive real single mode fiber. We investigate the influence of this ``oligo-mode'' fiber on the FDML laser performance. Two design configurations with 684,400 and 1,368,700 axial scans per second are investigated, 25x and 50x faster than current commercial instruments and more than 4x faster than previous single spot ophthalmic results. These high speeds enable the acquisition of densely sampled ultrawide-field data sets of the retina within a few seconds. Ultrawide-field data consisting of 1900 x 1900 A-scans with ~70{\textdegree} degrees angle of view are acquired within only 3 and 6 seconds using the different setups. Such OCT data sets, more than double as large as previously reported, are collapsed to a 4 megapixel high definition fundus image. We achieve good penetration into the choroid by hardware spectral shaping of the laser output. The axial resolution in tissue is 12{\textmu}m (684kHz) and 19{\textmu}m (1.37MHz). A series of new data processing and imaging extraction protocols, enabled by the ultrawide-field isotropic data sets, are presented. Dense isotropic sampling enables both, cross-sectional images along arbitrary coordinates and depth-resolved en-face fundus images. Additionally, we investigate how isotropic averaging compares to the averaging of cross-sections along the slow axis.},
}

@article{Alex2011,
   author = {Alex, A. and Weingast, J. and Hofer, B. and Eibl, M. and Binder, M. and Pehamberger, H. and Drexler, W. and Považay, B.},
   title = {3D optical coherence tomography for clinical diagnosis of nonmelanoma skin cancers},
   journal = {Imaging in Medicine},
   volume = {3},
   number = {6},
   keyword = {cancer diagnosis, contrast-enhanced imaging, dermatology, functional imaging,microscopy, multimodal imaging, optical coherence tomography, optical imaging, tomography},
  abstract = {High-resolution frequency domain optical coherence tomography (OCT) stands out amongst a range of novel dermatologic imaging technologies, with its good detection sensitivity around-100 dB, high measurement speeds allowing real-time image acquisition and its ability to acquire high definition cross-sectional and 3D tomograms of regions greater than 1 cm2, providing tissue information comparable to conventional histopathology without the need for any contrast agents. Typical axial and transverse resolutions of state-of-the-art OCT systems range between 1-10 m and approximately 20 m, respectively, depending on the employed wavelength region. This review investigates the significant progress accomplished in the field of dermatologic OCT with respect to other in vivo diagnostic methods for pre-excisional imaging of nonmelanoma skin cancers and specifically emphasizes state-of-the-art results achieved in different clinical pilot studies. Further technological extensions of OCT, various multimodal imaging approaches as well as potential clinical dermatologic applications are discussed. © 2011 Future Medicine Ltd.},
   pages = {653-674},
   url = {https://www.openaccessjournals.com/articles/3d-optical-coherence-tomography-for-clinical-diagnosis-of-nonmelanoma-skin-cancers-9179.html},
   year = {2011},
keywords = {AG-Huber, OCT},
   type = {Journal Article}
}

@article{Wieser:10,
author = {Wolfgang Wieser and Benjamin R. Biedermann and Thomas Klein and Christoph M. Eigenwillig and Robert Huber},
journal = {Opt. Photon. News},
keywords = {General; Analog to digital converters; Crystallography; Image quality; Optical coherence tomography; Real time imaging; Three dimensional imaging},
number = {12},
pages = {28--28},
publisher = {Optica Publishing Group},
title = {High-Quality 3-D Imaging withMultimegahertz OCT},
volume = {21},
month = {Dec},
year = {2010},
url = {https://www.optica-opn.org/abstract.cfm?URI=opn-21-12-28},
doi = {10.1364/OPN.21.12.000028},
abstract = {We have developed interferometric systems to measure nanosize structures and freeze their motion in time. Researchers have also suggested a method to extract both phase and amplitude information for crystallography.},
}

@article{Biedermann:10,
author = {Benjamin R. Biedermann and Wolfgang Wieser and Christoph M. Eigenwillig and Thomas Klein and Robert Huber},
journal = {Opt. Lett.},
keywords = {Optical coherence tomography; Lasers, tunable; Electrooptical modulators; Fourier transforms; Laser light; Laser sources; Optical coherence tomography; Swept lasers},
number = {22},
pages = {3733--3735},
publisher = {Optica Publishing Group},
title = {Direct measurement of the instantaneous linewidth of rapidly wavelength-swept lasers},
volume = {35},
month = {Nov},
year = {2010},
url = {https://opg.optica.org/ol/abstract.cfm?URI=ol-35-22-3733},
doi = {10.1364/OL.35.003733},
abstract = {The instantaneous linewidth of rapidly wavelength-swept laser sources as used for optical coherence tomography (OCT) is of crucial interest for a deeper understanding of physical effects involved in their operation. Swept lasers for OCT, typically sweeping over ~15 THz in ~10$\mu$s, have linewidths of several gigahertz. The high optical-frequency sweep speed makes it impossible to measure the instantaneous spectrum with standard methods. Hence, up to now, experimental access to the instantaneous linewidth was rather indirect by the inverse Fourier transform of the coherence decay. In this Letter, we present a method by fast synchronous time gating and extraction of a ``snapshot'' of the instantaneous spectrum with an electro-optic modulator, which can subsequently be measured with an optical spectrum analyzer. This new method is analyzed in detail, and systematic artifacts, such as sideband generation due to the modulation and residual wavelength uncertainty due to the sweeping operation, are quantified. The method is checked for consistency with results from the common, more indirect measurement via coherence properties.},
}

@article{Wieser:10,
author = {Wolfgang Wieser and Benjamin R. Biedermann and Thomas Klein and Christoph M. Eigenwillig and Robert Huber},
journal = {Opt. Express},
keywords = {Optical coherence tomography; Three-dimensional image acquisition; Lasers, tunable; Optical coherence tomography; Biological imaging; High speed imaging; Image processing algorithms; Image quality; Point spread function; Three dimensional imaging},
number = {14},
pages = {14685--14704},
publisher = {Optica Publishing Group},
title = {Multi-Megahertz OCT: High quality 3D imaging at 20 million A-scans and 4.5 GVoxels per second},
volume = {18},
month = {Jul},
year = {2010},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-18-14-14685},
doi = {10.1364/OE.18.014685},
abstract = {We present ultra high speed optical coherence tomography (OCT) with multi-megahertz line rates and investigate the achievable image quality. The presented system is a swept source OCT setup using a Fourier domain mode locked (FDML) laser. Three different FDML-based swept laser sources with sweep rates of 1, 2.6 and 5.2MHz are compared. Imaging with 4 spots in parallel quadruples the effective speed, enabling depth scan rates as high as 20.8 million lines per second. Each setup provides at least 98dB sensitivity and ~10{\textmu}m resolution in tissue. High quality 2D and 3D imaging of biological samples is demonstrated at full scan speed. A discussion about how to best specify OCT imaging speed is included. The connection between voxel rate, line rate, frame rate and hardware performance of the OCT setup such as sample rate, analog bandwidth, coherence length, acquisition dead-time and scanner duty cycle is provided. Finally, suitable averaging protocols to further increase image quality are discussed.},
}

@article{Marschall:10,
author = {Sebastian Marschall and Thomas Klein and Wolfgang Wieser and Benjamin R. Biedermann and Kevin Hsu and Kim P. Hansen and Bernd Sumpf and Karl-Heinz Hasler and G\"{o}tz Erbert and Ole B. Jensen and Christian Pedersen and Robert Huber and Peter E. Andersen},
journal = {Opt. Express},
keywords = {Optical coherence tomography; Lasers, tunable; Semiconductor lasers; Semiconductor optical amplifiers; Dispersion; High speed imaging; Laser light; Optical delay lines; Optical fibers; Optical standards; Swept sources},
number = {15},
pages = {15820--15831},
publisher = {Optica Publishing Group},
title = {Fourier domain mode-locked swept source at 1050 nm based on a tapered amplifier},
volume = {18},
month = {Jul},
year = {2010},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-18-15-15820},
doi = {10.1364/OE.18.015820},
abstract = {While swept source optical coherence tomography (OCT) in the 1050 nm range is promising for retinal imaging, there are certain challenges. Conventional semiconductor gain media have limited output power, and the performance of high-speed Fourier domain mode-locked (FDML) lasers suffers from chromatic dispersion in standard optical fiber. We developed a novel light source with a tapered amplifier as gain medium, and investigated the FDML performance comparing two fiber delay lines with different dispersion properties. We introduced an additional gain element into the resonator, and thereby achieved stable FDML operation, exploiting the full bandwidth of the tapered amplifier despite high dispersion. The light source operates at a repetition rate of 116 kHz with an effective average output power in excess of 30 mW. With a total sweep range of 70 nm, we achieved an axial resolution of 15 {\textmu}m in air (~11 {\textmu}m in tissue) in OCT measurements. As our work shows, tapered amplifiers are suitable gain media for swept sources at 1050 nm with increased output power, while high gain counteracts dispersion effects in an FDML laser.},
}

@inproceedings{10.1117/12.854238,
author = {Sebastian Marschall and Thomas Klein and Wolfgang Wieser and Benjamin Biedermann and Kevin Hsu and Bernd Sumpf and Karl-Heinz Hasler and G{\"o}tz Erbert and Ole B. Jensen and Christian Pedersen and Robert Huber and Peter E. Andersen},
title = {{High-power FDML laser for swept source-OCT at 1060 nm}},
volume = {7715},
booktitle = {Biophotonics: Photonic Solutions for Better Health Care II},
editor = {J{\"u}rgen Popp and Wolfgang Drexler and Valery V. Tuchin and Dennis L. Matthews},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {77150B},
abstract = {We present a novel frequency-swept light source working at 1060nm that utilizes a tapered amplifier as gain
medium. These devices feature significantly higher saturation power than conventional semiconductor optical
amplifiers and can thus improve the limited output power of swept sources in this wavelength range. We
demonstrate that a tapered amplifier can be integrated into a 
fiber-based swept source and allows for high-speed
FDML operation. The developed light source operates at a sweep rate of 116kHz with an effective average
output power in excess of 30mW. With a total sweep range of 70 nm an axial resolution of 15 μm in air (~11μm
in tissue) for OCT applications can be achieved.},
keywords = {optical coherence tomography, swept source, tunable laser, tapered amplifier, fourier domain mode-locking},
year = {2010},
doi = {10.1117/12.854238},
URL = {https://doi.org/10.1117/12.854238}
}

@inproceedings{Todor:10,
author = {Sebastian Todor and Christian Jirauschek and Benjamin Biedermann and Robert Huber},
booktitle = {Conference on Lasers and Electro-Optics 2010},
journal = {Conference on Lasers and Electro-Optics 2010},
keywords = {Lasers and laser optics; Laser theory; Lasers, tunable; Laser light; Laser operation; Mode locking; Optical amplifiers; Self phase modulation; Tunable lasers},
pages = {CMW7},
publisher = {Optica Publishing Group},
title = {Linewidth Optimization of Fourier Domain Mode-Locked Lasers},
year = {2010},
url = {https://opg.optica.org/abstract.cfm?URI=CLEO-2010-CMW7},
doi = {10.1364/CLEO.2010.CMW7},
abstract = {We theoretically and experimentally investigate the instantaneous linewidth of Fourier domain mode-locked lasers, yielding good agreement. Based on simulations, strategies are discussed to drastically reduce the laser linewidth.},
}

@inproceedings{10.1117/12.842011,
author = {Sebastian Marschall and Thomas Klein and Wolfgang Wieser and Benjamin Biedermann and Kevin Hsu and Bernd Sumpf and Karl-Heinz Hasler and G{\"o}tz Erbert and Ole B. Jensen and Christian Pedersen and Robert Huber and Peter E. Andersen},
title = {{FDML swept source at 1060 nm using a tapered amplifier}},
volume = {7554},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XIV},
editor = {Joseph A. Izatt and James G. Fujimoto and Valery V. Tuchin},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {75541H},
abstract = {We present a novel frequency-swept light source working at 1060nm that utilizes a tapered amplifier as gain
medium. These devices feature significantly higher saturation power than conventional semiconductor optical
amplifiers and can thus improve the limited output power of swept sources in this wavelength range. We
demonstrate that a tapered amplifier can be integrated into a fiber-based swept source and allows for high-speed
FDML operation. The developed light source operates at a sweep rate of 116kHz with an effective average
output power in excess of 30mW. With a total sweep range of 70 nm an axial resolution of 15 μm in air (~11μm in tissue) for OCT applications can be achieved.},
keywords = {optical coherence tomography, swept source, tunable laser, tapered amplifier, fourier domain mode-locking},
year = {2010},
doi = {10.1117/12.842011},
URL = {https://doi.org/10.1117/12.842011}
}

@article{Jirauschek:09,
author = {Christian Jirauschek and Benjamin Biedermann and Robert Huber},
journal = {Opt. Express},
keywords = {Laser theory; Lasers, tunable; Optical coherence tomography; Fourier domain mode locking; Laser modes; Laser sources; Mode locking; Optical amplifiers; Spontaneous emission},
number = {26},
pages = {24013--24019},
publisher = {Optica Publishing Group},
title = {A theoretical description of Fourier domain mode locked lasers},
volume = {17},
month = {Dec},
year = {2009},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-17-26-24013},
doi = {10.1364/OE.17.024013},
abstract = {The first theoretical model of Fourier domain mode locking operation is presented. A specially tailored dynamic equation in a moving spectral reference frame is derived, enabling efficient numerical treatment, despite the broad laser spectrum and the extremely long cavity. The excellent agreement of the presented theory with experiment over a wide range of operation parameters enables a quantitative assessment of the relevant physical effects, such as the spectral loss modulation and gain saturation dynamics, amplified spontaneous emission, linewidth enhancement, and self-phase modulation.},
}

@article{Wieser:09,
author = {Wolfgang Wieser and Benjamin R. Biedermann and Thomas Klein and Christoph M. Eigenwillig and Robert Huber},
journal = {Opt. Express},
keywords = {Fiber characterization; Fiber properties; Fibers, single-mode; Optical communications; Lasers, tunable; Dispersion; Optical standards and testing; Lasers, fiber; Fiber optic amplifiers; Laser modes; Laser sources; Mode locking; Optical networks; Thermal effects},
number = {25},
pages = {22871--22878},
publisher = {Optica Publishing Group},
title = {Ultra-rapid dispersion measurement in optical fibers},
volume = {17},
month = {Dec},
year = {2009},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-17-25-22871},
doi = {10.1364/OE.17.022871},
abstract = {We present a novel method to measure the chromatic dispersion of fibers with lengths of several kilometers. The technique is based on a rapidly swept Fourier domain mode locked laser driven at 50kHz repetition rate. Amplitude modulation with 400MHz and phase analysis yield the dispersion values over a 130nm continuous wavelength tuning range covering C and L band. The high acquisition speed of 10{\textmu}s for individual wavelength-resolved traces $\Delta$t($\lambda$) can reduce effects caused by thermal drift and acoustic vibrations. It enables real-time monitoring with update rates \>100Hz even when averaging several hundred acquisitions for improved accuracy.},
}

@INPROCEEDINGS{5343314,
  author={Huber, Robert},
  booktitle={2009 IEEE LEOS Annual Meeting Conference Proceedings}, 
  title={Advances in Fourier domain OCT}, 
  year={2009},
  volume={},
  number={},
  pages={201-202},
  abstract={In optical coherence tomography, the introduction of so called ldquoFrequency Domainrdquo techniques, i.e. spectrally resolved detection, had a dramatic impact on these biomedical imaging systems. The current status and future developments will be discussed.},
  keywords={},
  doi={10.1109/LEOS.2009.5343314},
  ISSN={1092-8081},
  month={Oct},}

@article{Ploetz:09,
author = {E. Ploetz and B. Marx and T. Klein and R. Huber and P. Gilch},
journal = {Opt. Express},
keywords = {Laser amplifiers; Ultrafast lasers; Nonlinear microscopy; Raman microscopy; Laser sources; Raman microscopy; Raman scattering; Raman spectroscopy; Stimulated Raman scattering; Time resolved spectroscopy},
number = {21},
pages = {18612--18620},
publisher = {Optica Publishing Group},
title = {A 75 MHz Light Source for Femtosecond Stimulated Raman Microscopy},
volume = {17},
month = {Oct},
year = {2009},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-17-21-18612},
doi = {10.1364/OE.17.018612},
abstract = {In femtosecond stimulated Raman microscopy (FSRM) a spectrally broad pulse (Raman probe) and a spectrally narrow pulse (Raman pump) interact in a sample and thereby generate a Raman spectrum of the focal volume. Here a novel light source for FSRM is presented. It consists of an 8-fs laser (repetition rate of 75 MHz) operating as Raman probe. A Yb3$+$ based fiber amplifier generates the Raman pump light at 980 nm. The amplifier is seeded by the spectral wing of the 8-fs laser output which ensures synchronisation of pump and probe pulses. Spectral and temporal characteristics of these pulses are reported and simultaneous recording of broadband Raman spectra relying on these pulses is demonstrated.},
}

@article{Eigenwillig:09,
author = {Christoph M. Eigenwillig and Benjamin R. Biedermann and Wolfgang Wieser and Robert Huber},
journal = {Opt. Express},
keywords = {Noise in imaging systems; Optical coherence tomography; Fabry-Perot; Filters; Interferometry; Lasers, tunable; Fiber Bragg grating sensors; Image quality; Light properties; Light sources; Medical imaging; Mode locking},
number = {21},
pages = {18794--18807},
publisher = {Optica Publishing Group},
title = {Wavelength swept amplified spontaneous emission source},
volume = {17},
month = {Oct},
year = {2009},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-17-21-18794},
doi = {10.1364/OE.17.018794},
abstract = {We present a new, alternative approach to realize a wavelength swept light source with no fundamental limit to sweep speed. Amplified spontaneous emission (ASE) light alternately passes a cascade of optical gain elements and tunable optical bandpass filters. We show that for high sweep speeds, the control signal for the different filters has to be applied with a defined, precise phase delay on the order of nanoseconds, to compensate for the light propagation time between the filters and ensure optimum operation. At a center wavelength of 1300 nm sweep rates of 10 kHz, 100 kHz and 340 kHz over a sweep range of 100 nm full width and an average power of 50 mW are demonstrated. For application in optical coherence tomography (OCT), an axial resolution of 12 {\textmu}m (air), a sensitivity of 120 dB (50 mW) and a dynamic range of 50 dB are achieved and OCT imaging is demonstrated. Performance parameters like coherence properties and relative intensity noise (RIN) are quantified, discussed and compared to the performance of Fourier Domain Mode Locked (FDML) lasers. Physical models for the observed difference in performance are provided.},
}

@article{Leonhardt:09,
author = {Rainer Leonhardt and Benjamin R. Biedermann and Wolfgang Wieser and Robert Huber},
journal = {Opt. Express},
keywords = {Fiber optics amplifiers and oscillators; Fibers, erbium; Lasers, tunable; Nonlinear optics, fibers; Nonlinear optics, four-wave mixing; Wavelength conversion devices ; Four wave mixing; Fourier domain mode locking; Laser sources; Optical coherence tomography; Optical frequency conversion; Semiconductor optical amplifiers},
number = {19},
pages = {16801--16808},
publisher = {Optica Publishing Group},
title = {Nonlinear optical frequency conversion of an amplified Fourier Domain Mode Locked (FDML) laser},
volume = {17},
month = {Sep},
year = {2009},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-17-19-16801},
doi = {10.1364/OE.17.016801},
abstract = {We report on the highly efficient non-linear optical frequency conversion of the wavelength swept output from a Fourier Domain Mode Locked (FDML) laser. Different concepts for power scaling of FDML lasers by post-amplification with active fibers are presented. A two-stage post-amplification of an FDML laser with an amplification factor of 300 up to a peak power of 1.5 W is used to supply sufficient power levels for non-linear conversion. Using a single-mode dispersion shifted fiber (DSF), we convert this amplified output that covers the region between 1541 nm and 1545 nm to a wavelength range from 1572 nm to 1663 nm via modulation instability (MI). For this four wave mixing process we observe an efficiency of ~40\%. The anti-Stokes signal between 1435 nm and 1516 nm was observed with lower conversion efficiency. In addition to shifting the wavelength, the effect of MI also enables a substantial increase in the wavelength sweep rate of the FDML laser by a factor of ~50 to 0.55 nm/ns.},
}

@article{Gora:09,
author = {Michalina Gora and Karol Karnowski and Maciej Szkulmowski and Bartlomiej J. Kaluzny and Robert Huber and Andrzej Kowalczyk and Maciej Wojtkowski},
journal = {Opt. Express},
keywords = {Optical coherence tomography; Lasers, tunable; Ophthalmology; Crystalline lens; High speed imaging; Imaging systems; Ophthalmic imaging; Optical coherence tomography; Three dimensional imaging},
number = {17},
pages = {14880--14894},
publisher = {Optica Publishing Group},
title = {Ultra high-speed swept source OCT imaging of the anterior segment of human eye at 200 kHz with adjustable imaging range},
volume = {17},
month = {Aug},
year = {2009},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-17-17-14880},
doi = {10.1364/OE.17.014880},
abstract = {We present an application of in vivo anterior segment imaging of the human eye with an ultrahigh speed swept source OCT instrument. For this purpose, a dedicated OCT system was designed and constructed. This instrument enables axial zooming by automatic reconfiguration of spectral sweep range; an enhanced imaging range mode enables imaging of the entire anterior segment while a high axial resolution mode provides detailed morphological information of the chamber angle and the cornea. The speed of 200,000 lines/s enables high sampling density in three-dimensional imaging of the entire cornea in 250 ms promising future applications of OCT for optical corneal topography, pachymetry and elevation maps. The results of a preliminary quantitative corneal analysis based on OCT data free form motion artifacts are presented. Additionally, a volumetric and real time reconstruction of dynamic processes, like pupillary reaction to light stimulus or blink-induced contact lens movements are demonstrated.},
}

@inproceedings{10.1117/12.831831,
author = {Christoph M. Eigenwillig and Benjamin R. Biedermann and Wolfgang Wieser and Robert Huber},
title = {{Wavelength swept ASE source}},
volume = {7372},
booktitle = {Optical Coherence Tomography and Coherence Techniques IV},
editor = {Peter E. Andersen and Brett E. Bouma},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {73720O},
abstract = {We present a novel wavelength swept light source for Optical Coherence Tomography (OCT). Arbitrary sweep rates up
to 2x170kHz are achieved by phase-shifted control of two optical bandpass-filters to compensate light propagation
effects.},
keywords = {amplified spontaneous emission, tunable lasers, lasers, optical coherence tomography, optical frequency domain imaging},
year = {2009},
doi = {10.1117/12.831831},
URL = {https://doi.org/10.1117/12.831831}
}

@inproceedings{10.1117/12.831835,
author = {Gesa Palte and Wolfgang Wieser and Benjamin R. Biedermann and Christoph M. Eigenwillig and Robert Huber},
title = {{Fourier domain mode locked (FDML) lasers for polarization sensitive OCT}},
volume = {7372},
booktitle = {Optical Coherence Tomography and Coherence Techniques IV},
editor = {Peter E. Andersen and Brett E. Bouma},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {73720M},
abstract = {A Fourier Domain mode-locked (FDML) laser for polarization sensitive optical coherence tomography (OCT) is
presented. The laser generates an alternating sequence of wavelength sweeps with their polarization states 90° separated
on the Poincare sphere.},
keywords = {Lasers, tunable, optical coherence tomography, lasers, imaging systems, polarization, fiber},
year = {2009},
doi = {10.1117/12.831835},
URL = {https://doi.org/10.1117/12.831835}
}

@article{https://doi.org/10.1002/jbio.200910028,
author = {Biedermann, Benjamin R. and Wieser, Wolfgang and Eigenwillig, Christoph M. and Huber, Robert},
title = {Recent developments in Fourier Domain Mode Locked lasers for optical coherence tomography: Imaging at 1310 nm vs. 1550 nm wavelength},
journal = {Journal of Biophotonics},
volume = {2},
number = {6-7},
pages = {357-363},
keywords = {optical coherence tomography, tunable lasers, Fourier domain mode locking, optical frequency domain imaging},
doi = {https://doi.org/10.1002/jbio.200910028},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/jbio.200910028},
eprint = {https://onlinelibrary.wiley.com/doi/pdf/10.1002/jbio.200910028},
abstract = {Abstract We report on recent progress in Fourier domain mode-locking (FDML) technology. The paper focuses on developments beyond pushing the speed of these laser sources. After an overview of improvements to FDML over the last three years, a brief analysis of OCT imaging using FDML lasers with different wavelengths is presented. For the first time, high speed, high quality FDML imaging at 1550 nm is presented and compared to a system at 1310 nm. The imaging results of human skin for both wavelengths are compared and analyzed. Sample arm optics, power on the sample, heterodyne gain, detection bandwidth, colour cut levels and sample location have been identical to identify the influence of difference in scattering and water absorption. The imaging performance at 1310 nm in human skin is only slightly better and the results suggest that water absorption only marginally affects the penetration depth in human skin at 1550 nm. For several applications this wavelength may be preferred. (© 2009 WILEY-VCH Verlag GmbH \& Co. KGaA, Weinheim)},
year = {2009}
}

@INPROCEEDINGS{5192900,
  author={Biedermann, Benjamin R. and Wieser, Wolfgang and Eigenwillig, Christoph M. and Klein, Thomas and Huber, Robert},
  booktitle={CLEO/Europe - EQEC 2009 - European Conference on Lasers and Electro-Optics and the European Quantum Electronics Conference}, 
  title={Dispersion, coherence and noise of Fourier Domain Mode Locked (FDML) lasers}, 
  year={2009},
  volume={},
  number={},
  pages={1-1},
  abstract={We present a detailed analysis of coherence and noise of the FDML laser, depending on filter drive frequency, detuning and amount of cavity dispersion. The results provide insight into phase and amplitude noise of the laser light itself. We address the following two questions: (1) How much dispersion compensation is necessary for optimum laser performance in FDML for a certain width of the optical band pass filter? (2) How are timing mismatch effects, caused by either detuning of the drive frequency or chromatic dispersion in the cavity of the filter, related to coherence length and noise?},
  keywords={},
  doi={10.1109/CLEOE-EQEC.2009.5192900},
  ISSN={},
  month={June},}

@INPROCEEDINGS{5191695,
  author={Huber, Robert},
  booktitle={CLEO/Europe - EQEC 2009 - European Conference on Lasers and Electro-Optics and the European Quantum Electronics Conference}, 
  title={State-of-the-art and future of ultrahigh speed OCT}, 
  year={2009},
  volume={},
  number={},
  pages={1-1},
  abstract={This paper reviews the current status of high speed OCT systems on the different levels of development: commercial, laboratory prototype style and proof of concept type systems. The pro and contra of SD-OCT and SS-OCT are discussed and an analysis of the desired optimum imaging speeds for various applications. SS-OCT systems are used for imaging in highly scattering tissue ~1300 nm, a line rate of 60 MHz was achieved by with SD-OCT.},
  keywords={},
  doi={10.1109/CLEOE-EQEC.2009.5191695},
  ISSN={},
  month={June},}

@INPROCEEDINGS{5194704,
  author={Klein, Thomas and Wieser, Wolfgang and Biedermann, Benjamin R. and Eigenwillig, Christoph M. and Palte, Gesa and Huber, Robert},
  booktitle={CLEO/Europe - EQEC 2009 - European Conference on Lasers and Electro-Optics and the European Quantum Electronics Conference}, 
  title={Raman pumped Fourier Domain Mode Locked (FDML) laser: Analysis of operation and application for optical coherence tomography (OCT)}, 
  year={2009},
  volume={},
  number={},
  pages={1-1},
  abstract={limitations of the sweep repetition rate of rapidly wavelength swept laser sources. Such sources can be applied for optical coherence tomography (OCT) using frequency domain detection. This technique is called swept source OCT (ss-OCT) or optical frequency domain imaging (OFDI). FDML lasers usually consist of a semiconductor optical amplifier (SOA) as laser gain medium, an output coupler, a periodically driven optical band-pass filter (FFP-TF) and an optical delay line, so that their total length is typically several kilometres.},
  keywords={},
  doi={10.1109/CLEOE-EQEC.2009.5194704},
  ISSN={},
  month={June},}

@article{Biedermann:09,
author = {Benjamin R. Biedermann and Wolfgang Wieser and Christoph M. Eigenwillig and Thomas Klein and Robert Huber},
journal = {Opt. Express},
keywords = {Noise in imaging systems; Optical coherence tomography; Interferometry; Lasers, tunable; Optical coherence tomography; Dispersion; Laser light; Laser modes; Laser operation; Laser sources; Mode locking; Swept lasers},
number = {12},
pages = {9947--9961},
publisher = {Optica Publishing Group},
title = {Dispersion, coherence and noise of Fourier domain mode locked lasers},
volume = {17},
month = {Jun},
year = {2009},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-17-12-9947},
doi = {10.1364/OE.17.009947},
abstract = {We report on the effect of chromatic dispersion on coherence length and noise of Fourier Domain Mode Locked (FDML) lasers. An FDML laser with a sweep range of 100nm around 1550nm has been investigated. Cavity configurations with and without dispersion compensation have been analyzed using different widths of the intra-cavity optical band-pass filter. The measurements are compared to non-FDML wavelength swept laser sources. Based on these observations, a simple model is developed providing a connection between timing, photon cavity lifetime and characteristic time constant of the filter. In an optimized configuration, an instantaneous laser linewidth of 20pm is observed, corresponding to a 10{\texttimes} narrowing compared to the intra-cavity optical band-pass filter. A relative intensity noise of -133dBc/Hz or 0.2\% at 100MHz detection bandwidth during sweep operation is observed. For optimum operation, the filter drive frequency has to be set within 2ppm or 120mHz at 51kHz.},
}

@article{Eigenwillig:09,
author = {Christoph M. Eigenwillig and Wolfgang Wieser and Benjamin R. Biedermann and Robert Huber},
journal = {Opt. Lett.},
keywords = {Coherence imaging; Optical coherence tomography; Three-dimensional image acquisition; Lasers, tunable; Medical and biological imaging; Optical coherence tomography; Fourier domain mode locking; Laser operation; Laser sources; Laser systems; Mode locking; Optical coherence tomography},
number = {6},
pages = {725--727},
publisher = {Optica Publishing Group},
title = {Subharmonic Fourier domain mode locking},
volume = {34},
month = {Mar},
year = {2009},
url = {https://opg.optica.org/ol/abstract.cfm?URI=ol-34-6-725},
doi = {10.1364/OL.34.000725},
abstract = {We demonstrate a subharmonically Fourier domain mode-locked wavelength-swept laser source with a substantially reduced cavity fiber length. In contrast to a standard Fourier domain mode-locked configuration, light is recirculated repetitively in the delay line with the optical bandpass filter used as switch. The laser has a fundamental optical round trip frequency of 285 kHz and can be operated at integer fractions thereof (subharmonics). Sweep ranges up to 95 nm full width centred at 1317 nm are achieved at the 1/5th subharmonic. A maximum sensitivity of 116 dB and an axial resolution of 12 $\mu$m in air are measured at an average sweep power of 12 mW. A sensitivity roll-off of 11 dB over 4 mm and 25 dB over 10 mm is observed and optical coherence tomography imaging is demonstrated. Besides the advantage of a reduced fiber length, subharmonic Fourier domain mode locking (shFDML) enables simple scaling of the sweep speed by extracting light from the delay part of the resonator. A sweep rate of 570 kHz is achieved. Characteristic features of shFDML operation, such as power leakage during fly-back and cw breakthrough, are investigated.},
}

@inproceedings{10.1117/12.808555,
author = {Karol Karnowski and Michalina Gora and Bartlomiej Kaluzny and Robert Huber and Maciej Szkulmowski and Andrzej Kowalczyk and Maciej Wojtkowski},
title = {{Swept source OCT imaging of human anterior segment at 200 kHz}},
volume = {7163},
booktitle = {Ophthalmic Technologies XIX},
editor = {Fabrice Manns and Per G. S{\"o}derberg and Arthur Ho},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {716308},
abstract = {We present applicability of the high speed swept-source optical coherence tomography for in vivo imaging of the anterior segment of the human eye. Three dimensional imaging of the cornea with reduced motion artifacts is possible by using swept source with Fourier domain mode locking operating at 200kHz with 1300nm central wavelength. High imaging speeds allow for assessment of anterior and posterior corneal topography and generation of thickness and elevation maps.},
keywords = {Optical Coherence Tomography, Fourier domain detection methods, swept source OCT, anterior segment of the eye},
year = {2009},
doi = {10.1117/12.808555},
URL = {https://doi.org/10.1117/12.808555}
}

@Misc{HU_2009_Huber_b,
  Title                    = {{Fourier domain mode locking: new lasers for optical coherence tomography}},

  Author                   = {Huber, Robert},
  Year                     = {2009},

  Booktitle                = {SPIE Newsroom},
  Doi                      = {10.1117/2.1200901.1440},
  ISSN                     = {18182259},
keywords = {AG-Huber_FDML, AG-Huber_OCT},
  Url                      = {http://www.spie.org/x33321.xml}
}

@article{Klein:08,
author = {Thomas Klein and Wolfgang Wieser and Benjamin R. Biedermann and Christoph M. Eigenwillig and Gesa Palte and Robert Huber},
journal = {Opt. Lett.},
keywords = {Optical coherence tomography; Lasers, fiber; Lasers, Raman; Lasers, tunable; Optical coherence tomography; Laser operation; Mode locking; Optical coherence tomography; Optical components; Raman fiber lasers; Semiconductor lasers},
number = {23},
pages = {2815--2817},
publisher = {Optica Publishing Group},
title = {Raman-pumped Fourier-domain mode-locked laser: analysis of operation and application for optical coherence tomography},
volume = {33},
month = {Dec},
year = {2008},
url = {https://opg.optica.org/ol/abstract.cfm?URI=ol-33-23-2815},
doi = {10.1364/OL.33.002815},
abstract = {We demonstrate a Raman-pumped Fourier-domain mode-locked (FDML) fiber laser and optical coherence tomography imaging with this source. The wavelength sweep range of only 30 nm centered around 1550 nm results in limited axial resolution, hence a nonbiological sample is imaged. An output power of 1.9 mW was achieved at a sweep rate of 66 kHz and a maximum ranging depth of ~2.5 cm. Roll-off characteristics are found to be similar to FDML lasers with semiconductor optical amplifiers as gain media. The application of Raman gain also enables unperturbed cavity ring-down experiments in FDML lasers for the first time, providing direct access to the photon lifetime in the laser cavity. Good agreement with nonswept cw operation is proof of the stationary operation of FDML lasers.},
}

@article{10.1167/iovs.08-2127,
    author = {Srinivasan, Vivek J. and Adler, Desmond C. and Chen, Yueli and Gorczynska, Iwona and Huber, Robert and Duker, Jay S. and Schuman, Joel S. and Fujimoto, James G.},
    title = "{Ultrahigh-Speed Optical Coherence Tomography for Three-Dimensional and En Face Imaging of the Retina and Optic Nerve Head}",
    journal = {Investigative Ophthalmology & Visual Science},
    volume = {49},
    number = {11},
    pages = {5103-5110},
    year = {2008},
    month = {11},
    abstract = "{  purpose. To demonstrate ultrahigh-speed optical coherence tomography (OCT) imaging of the retina and optic nerve head at 249,000 axial scans per second and a wavelength of 1060 nm. To investigate methods for visualization of the retina, choroid, and optic nerve using high-density sampling enabled by improved imaging speed.  methods. A swept-source OCT retinal imaging system operating at a speed of 249,000 axial scans per second was developed. Imaging of the retina, choroid, and optic nerve were performed. Display methods such as speckle reduction, slicing along arbitrary planes, en face visualization of reflectance from specific retinal layers, and image compounding were investigated.  results. High-definition and three-dimensional (3D) imaging of the normal retina and optic nerve head were performed. Increased light penetration at 1060 nm enabled improved visualization of the choroid, lamina cribrosa, and sclera. OCT fundus images and 3D visualizations were generated with higher pixel density and less motion artifacts than standard spectral/Fourier domain OCT. En face images enabled visualization of the porous structure of the lamina cribrosa, nerve fiber layer, choroid, photoreceptors, RPE, and capillaries of the inner retina.  conclusions. Ultrahigh-speed OCT imaging of the retina and optic nerve head at 249,000 axial scans per second is possible. The improvement of ∼5 to 10× in imaging speed over commercial spectral/Fourier domain OCT technology enables higher density raster scan protocols and improved performance of en face visualization methods. The combination of the longer wavelength and ultrahigh imaging speed enables excellent visualization of the choroid, sclera, and lamina cribrosa. }",
    issn = {1552-5783},
    doi = {10.1167/iovs.08-2127},
    url = {https://doi.org/10.1167/iovs.08-2127},
    eprint = {https://arvojournals.org/arvo/content\_public/journal/iovs/932946/z7g01108005103.pdf},
}