@article{Hillmann2013,
   author = {Hillmann, Dierck and Franke, Gesa and Hinkel, Laura and Bonin, Tim and Koch, Peter and Hüttmann, Gereon},
   title = {Off-axis full-field swept-source optical coherence tomography using holographic refocusing},
   pages = {857104-857104},
   note = {10.1117/12.2006436},
   abstract = {We demonstrate a full-field swept-source OCT using an off-axis geometry of the reference illumination. By using holographic refocusing techniques, a uniform lateral resolution is achieved over the measurement depth of approximately 80 Rayleigh lengths. Compared to a standard on-axis setup, artifacts and autocorrelation signals are suppressed and the measurement depth is doubled by resolving the complex conjugate ambiguity. Holographic refocusing was done efficiently by Fourier-domain resampling as demonstrated before in inverse scattering and holoscopy. It allowed to reconstruct a complete volume with about 10μm resolution over the complete measurement depth of more than 10mm. Off-axis full-field swept-source OCT enables high measurement depths, spanning many Rayleigh lengths with reduced artifacts.},
   DOI = {10.1117/12.2006436},
   url = {http://dx.doi.org/10.1117/12.2006436},
   year = {2013},
   type = {Journal Article}
}

@article{Franke2013,
   author = {Franke, Gesa Lilith and Hillmann, Dierck and Lührs, Christian and Koch, Peter and Wollenzin, Jörn and Hüttmann, Gereon},
   title = {Towards microscopic resolution in holoscopy},
   pages = {85711O-85711O},
   note = {10.1117/12.2006806},
   abstract = {Holoscopy is a new imaging approach combining digital holography and full-field Fourier-domain optical coherence tomography. The interference pattern between light scattered by a sample and a defined reference wave is recorded and processed numerically. During reconstruction numerical refocusing is applied, overcoming the limitation of the focal depth and thus a uniform, diffraction limited lateral resolution over the whole measurement depth can be obtained. The advantage of numerical refocusing becomes especially significant for imaging at high numerical apertures (NAs). We use a high-resolution setup based on a Mach-Zehnder interferometer with an high-resolution microscope objective (NA = 0.75). For reliable reconstruction of a sample volume the Rayleigh length of the microscope objective and the axial resolution, given by the spectral range of the light source, need to be matched. For a 0.75 NA objective a tunable light source with a sweeping range of ! 300nm is required. Here we present as a first step a tunable Ti:sapphire laser with a tuning range of 187 nm. By characterizing the spectral properties of the Ti:sapphire laser and determining the axial point spread function we demonstrate the feasibility of this light source for high-resolution holoscopy.},
   DOI = {10.1117/12.2006806},
   url = {http://dx.doi.org/10.1117/12.2006806},
   year = {2013},
   type = {Journal Article}
}

@inproceedings{Fink2013,
   author = {Fink, Peer K and Hillmann, Dierck and Franke, Gesa L and Ramm, Dirk and Koch, P and Hüttmann, Gereon},
   title = {Stray light rejection by structured illumination},
   booktitle = {Studierendentagung},
   publisher = {Universität zu Lübeck},
   type = {Conference Proceedings},
year = { 2013}
}

@inproceedings{Franke-2012,
   author = {Franke, Gesa Lilith and Hillmann, Dierck and Claussen, Thorsten and Luhrs, Christian and Koch, Peter and Huttmann, Gereon},
   title = {High resolution holoscopy},
   editor = {Joseph, A. Izatt and James, G. Fujimoto and Valery, V. Tuchin},
   publisher = {SPIE},
   volume = {8213},
   pages = {821324},
URL = { https://doi.org/10.1117/12.911166},
year = { 2012}

}

@article{Hillmann2012,
   author = {Hillmann, Dierck and Franke, Gesa and Lührs, Christian and Koch, Peter and Hüttmann, Gereon},
   title = {Efficient holoscopy image reconstruction},
   journal = {Opt. Express},
   volume = {20},
   number = {19},
   pages = {21247-21263},
   abstract = {Holoscopy is a tomographic imaging technique that combines digital holography and Fourier-domain optical coherence tomography (OCT) to gain tomograms with diffraction limited resolution and uniform sensitivity over several Rayleigh lengths. The lateral image information is calculated from the spatial interference pattern formed by light scattered from the sample and a reference beam. The depth information is obtained from the spectral dependence of the recorded digital holograms. Numerous digital holograms are acquired at different wavelengths and then reconstructed for a common plane in the sample. Afterwards standard Fourier-domain OCT signal processing achieves depth discrimination. Here we describe and demonstrate an optimized data reconstruction algorithm for holoscopy which is related to the inverse scattering reconstruction of wavelength-scanned full-field optical coherence tomography data. Instead of calculating a regularized pseudoinverse of the forward operator, the recorded optical fields are propagated back into the sample volume. In one processing step the high frequency components of the scattering potential are reconstructed on a non-equidistant grid in three-dimensional spatial frequency space. A Fourier transform yields an OCT equivalent image of the object structure. In contrast to the original holoscopy reconstruction with backpropagation and Fourier transform with respect to the wavenumber, the required processing time does neither depend on the confocal parameter nor on the depth of the volume. For an imaging NA of 0.14, the processing time was decreased by a factor of 15, at higher NA the gain in reconstruction speed may reach two orders of magnitude.},
   keywords = {Image processing
Optical coherence tomography
Digital holography},
   year = {2012}
}

@article{Hillmann2012,
   author = {Hillmann, Dierck and Bonin, Tim and Lührs, Christian and Franke, Gesa and Hagen-Eggert, Martin and Koch, Peter and Hüttmann, Gereon},
   title = {Common approach for compensation of axial motion artifacts in swept-source OCT and dispersion in Fourier-domain OCT},
   journal = {Opt. Express},
   volume = {20},
   number = {6},
   pages = {6761-6776},
   abstract = {Swept-source optical coherence tomography (SS-OCT) is sensitive to sample motion during the wavelength sweep, which leads to image blurring and image artifacts. In line-field and full-field SS-OCT parallelization is achieved by using a line or area detector, respectively. Thus, approximately 1000 lines or images at different wavenumbers are acquired. The sweep duration is identically with the acquisition time of a complete B-scan or volume, rendering parallel SS-OCT more sensitive to motion artifacts than scanning OCT. The effect of axial motion on the measured spectra is similar to the effect of non-balanced group velocity dispersion (GVD) in the interferometer arms. It causes the apparent optical path lengths in the sample arm to vary with the wavenumber. Here we propose the cross-correlation of sub-bandwidth reconstructions (CCSBR) as a new algorithm that is capable of detecting and correcting the artifacts induced by axial motion in line-field or full-field SS-OCT as well as GVD mismatch in any Fourier-domain OCT (FD-OCT) setup. By cross-correlating images which were reconstructed from a limited spectral range of the interference signal, a phase error is determined which is used to correct the spectral modulation prior to the calculation of the A-scans. Performance of the algorithm is demonstrated on in vivo full-field SS-OCT images of skin and scanning FD-OCT of skin and retina.},
   keywords = {Image reconstruction-restoration
Optical coherence tomography},
   year = {2012}
}

@article{Hillmann2012,
   author={Hillmann, D.  and Bonin, T.  and Luhrs, C.  and Franke, G.  and Hagen-Eggert, M.  and Koch, P.  and Huttmann, G. },
   title={{{C}ommon approach for compensation of axial motion artifacts in swept-source {O}{C}{T} and dispersion in {F}ourier-domain {O}{C}{T}}},
   journal={Opt Express},
   year={2012},
   volume={20},
   number={6},
   pages={6761--6776},
   month={Mar}
}

@article{Hillmann2011-1,
   author = {Hillmann, D. and Luhrs, C. and Bonin, T. and Koch, P. and Huttmann, G.},
   title = {Holoscopy--holographic optical coherence tomography},
   journal = {Opt Lett},
   volume = {36},
   number = {13},
   pages = {2390-2},
   abstract = {Scanning optical coherence tomography (OCT) is limited in sensitivity and resolution by the restricted focal depth of the confocal detection scheme. Holoscopy, a combination of holography and Fourier-domain full-field OCT, is proposed as a way to detect photons from all depths of a sample volume simultaneously with uniform sensitivity and lateral resolution, even at high NAs. By using the scalar diffraction theory, as frequently applied in digital holographic imaging, we fully reconstruct the object field with depth-invariant imaging quality. In vivo imaging of human skin is demonstrated with an image quality comparable to conventionally scanned OCT.},
   keywords = {Fingers
Fourier Analysis
Holography/*methods
Humans
Photons
Tomography, Optical Coherence/*methods},
   ISSN = {1539-4794 (Electronic)
0146-9592 (Linking)},
   DOI = {10.1364/OL.36.002390},
   url = {http://www.ncbi.nlm.nih.gov/pubmed/21725421},
   year = {2011},
   type = {Journal Article}
}

@inproceedings{Hagen-Eggert2011,
   author = {Hagen-Eggert, M. and Hillmann, D. and Koch, P. and Huttmann, G.},
   title = {Diffusion-sensitive Fourier-domain optical coherence tomography},
   editor = {James, G. Fujimoto and Joseph, A. Izatt and Valery, V. Tuchin},
   publisher = {SPIE},
   volume = {7889},
   pages = {78892B},

}

@inproceedings{Hillmann2011,
   author = {Hillmann, Dierck and Luhrs, Christian  and Bonin, Tim  and Koch, Peter and Vogel, Alfred  and Huttmann, Gereon },
   title = {Holoscopy: holographic optical coherence tomography},
   editor = {Rainer, A. Leitgeb and Brett, E. Bouma},
   publisher = {Proc. SPIE},
   volume = {8091},
   pages = {80911H},
   url = {http://link.aip.org/link/?PSI/8091/80911H/1
http://dx.doi.org/10.1117/12.889485},
   type = {Conference Proceedings},
year = { 2011}
}

@article{Probst2010,
   author = {Probst, Joachim and Hillmann, Dierck and Lankenau, Eva and Winter, Christan and Oelckers, Stefan and Koch, Peter and Huttmann, Gereon},
   title = {Optical coherence tomography with online visualization of more than seven rendered volumes per second},
   journal = {Journal of Biomedical Optics},
   volume = {15},
   number = {2},
   pages = {026014},
   keywords = {image resolution
medical image processing
optical tomography
rendering (computer graphics)
surgery},
   year = {2010}
}

@inproceedings{Hillmann,
   author = {Hillmann, Dierck and Huttmann, Gereon and Koch, Peter},
   title = {Using nonequispaced fast Fourier transformation to process optical coherence tomography signals},
   editor = {Peter, E. Andersen and Brett, E. Bouma},
   publisher = {SPIE},
   volume = {7372},
   pages = {73720R},
url = { https://doi.org/10.1364/ECBO.2009.7372_0R},
year = { 2009}

}