The Experts below are selected from a list of 21849 Experts worldwide ranked by ideXlab platform
Yoshiaki Yasuno - One of the best experts on this subject based on the ideXlab platform.
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advanced multi contrast jones matrix optical coherence tomography for doppler and Polarization sensitive imaging
Optics Express, 2013Co-Authors: Youngjoo Hong, Shuichi Makita, Lian Duan, Masahiro Miura, Yiheng Lim, Kazuhiro Kurokawa, Shuo Tang, Yoshiaki YasunoAbstract:An advanced version of Jones matrix optical coherence tomography (JMT) is demonstrated for Doppler and Polarization sensitive imaging of the posterior eye. JMT is capable of providing localized flow tomography by Doppler detection and investigating the birefringence property of tissue through a three-dimensional (3-D) Jones matrix measurement. Owing to an Incident Polarization multiplexing scheme based on passive optical components, this system is stable, safe in a clinical environment, and cost effective. Since the properties of this version of JMT provide intrinsic compensation for system imperfection, the system is easy to calibrate. Compared with the previous version of JMT, this advanced JMT achieves a sufficiently long depth measurement range for clinical cases of posterior eye disease. Furthermore, a fine spectral shift compensation method based on the cross-correlation of calibration signals was devised for stabilizing the phase of OCT, which enables a high sensitivity Doppler OCT measurement. In addition, a new theory of JMT which integrates the Jones matrix measurement, Doppler measurement, and scattering measurement is presented. This theory enables a sensitivity-enhanced scattering OCT and high-sensitivity Doppler OCT. These new features enable the application of this system to clinical cases. A healthy subject and a geographic atrophy patient were measured in vivo, and simultaneous imaging of choroidal vasculature and birefringence structures are demonstrated.
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passive component based multifunctional jones matrix swept source optical coherence tomography for doppler and Polarization imaging
Optics Letters, 2012Co-Authors: Youngjoo Hong, Lian Duan, Yoshiaki YasunoAbstract:We present a fiber based multifunctional Jones matrix swept source optical coherence tomography (SS-OCT) system for Doppler and Polarization imaging. Jones matrix measurement without using active components such as electro-optic modulators is realized by Incident Polarization multiplexing based on independent delay of two orthogonal Polarization states and Polarization diversity detection. In addition to Polarization sensitivity, this system measures Doppler flow without extra hardware for phase stabilized SS-OCT detection. An eighth-wave plate was measured to demonstrate the Polarization detection accuracy. The optic nerve head of a retina was measured in vivo. Detailed vasculature and birefringent structures were investigated simultaneously.
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Polarization sensitive swept source optical coherence tomography with continuous source Polarization modulation
Optics Express, 2008Co-Authors: Masahiro Yamanari, Shuichi Makita, Yoshiaki YasunoAbstract:We present fiber-based Polarization-sensitive swept-source optical coherence tomography (SS-OCT) based on continuous source Polarization modulation. The light source is a frequency swept laser centered at 1.31 µm with a scanning rate of 20 kHz. The Incident Polarization is modulated by a resonant electro-optic modulator at 33.3 MHz, which is one-third of the data acquisition frequency. The zeroth- and first-order harmonic components of the OCT signals with respect to the Polarization modulation frequency have the polarimetric information of the sample. By algebraic and matrix calculations of the signals, this system can measure the depth-resolved Jones matrices of the sample with a single wavelength scan. The phase fluctuations of the starting trigger of wavelength scan and the Polarization modulation are cancelled by monitoring the OCT phase of a calibration mirror inserted into the sample arm. We demonstrate the potential of the system by the measurement of chicken breast muscle and the volumetric measurement of an in vivo human anterior eye segment. The phase retardation image shows an additional contrast in the fibrous tissue such as the collagen fiber in the trabecular meshwork and sclera.
Johannes F De Boer - One of the best experts on this subject based on the ideXlab platform.
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jones matrix analysis for a Polarization sensitive optical coherence tomography system using fiber optic components
Optics Letters, 2004Co-Authors: Hyle B Park, Mark C Pierce, Barry Cense, Johannes F De BoerAbstract:We present an analysis for Polarization-sensitive optical coherence tomography that facilitates the unrestricted use of fiber and fiber-optic components throughout an interferometer and yields sample birefringence, diattenuation, and relative optic axis orientation. We use a novel Jones matrix approach that compares the Polarization states of light reflected from the sample surface with those reflected from within a biological sample for pairs of depth scans. The Incident Polarization alternated between two states that are perpendicular in a Poincare sphere representation to ensure proper detection of tissue birefringence regardless of optical fiber contributions. The method was validated by comparing the calculated diattenuation of a polarizing sheet, chicken tendon, and muscle with that obtained by independent measurement. The relative importance of diattenuation versus birefringence to angular displacement of Stokes vectors on a Poincare sphere was quantified.
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in vivo burn depth determination by high speed fiber based Polarization sensitive optical coherence tomography
Journal of Biomedical Optics, 2001Co-Authors: B H Park, C E Saxer, Shyam M Srinivas, J S Nelson, Johannes F De BoerAbstract:We report the first application of high-speed fiber-based po- larization sensitive optical coherence tomography (PS-OCT) to image burned tissue in vivo. Thermal injury denatures collagen in skin and PS-OCT can measure the reduction in collagen birefringence using depth resolved changes in the Polarization state of light propagated in, and reflected from, the tissue. Stokes vectors were calculated for each point in a scan and birefringence relative to Incident Polarization de- termined using four Incident Polarization states. Using a high-speed fiber-based PS-OCT system on rat skin burned for varying periods of time, a correlation between birefringence and actual burn depth de- termined by histological analysis was established. In conclusion, PS- OCT has potential use for noninvasive assessment of burn depth.
Youngjoo Hong - One of the best experts on this subject based on the ideXlab platform.
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advanced multi contrast jones matrix optical coherence tomography for doppler and Polarization sensitive imaging
Optics Express, 2013Co-Authors: Youngjoo Hong, Shuichi Makita, Lian Duan, Masahiro Miura, Yiheng Lim, Kazuhiro Kurokawa, Shuo Tang, Yoshiaki YasunoAbstract:An advanced version of Jones matrix optical coherence tomography (JMT) is demonstrated for Doppler and Polarization sensitive imaging of the posterior eye. JMT is capable of providing localized flow tomography by Doppler detection and investigating the birefringence property of tissue through a three-dimensional (3-D) Jones matrix measurement. Owing to an Incident Polarization multiplexing scheme based on passive optical components, this system is stable, safe in a clinical environment, and cost effective. Since the properties of this version of JMT provide intrinsic compensation for system imperfection, the system is easy to calibrate. Compared with the previous version of JMT, this advanced JMT achieves a sufficiently long depth measurement range for clinical cases of posterior eye disease. Furthermore, a fine spectral shift compensation method based on the cross-correlation of calibration signals was devised for stabilizing the phase of OCT, which enables a high sensitivity Doppler OCT measurement. In addition, a new theory of JMT which integrates the Jones matrix measurement, Doppler measurement, and scattering measurement is presented. This theory enables a sensitivity-enhanced scattering OCT and high-sensitivity Doppler OCT. These new features enable the application of this system to clinical cases. A healthy subject and a geographic atrophy patient were measured in vivo, and simultaneous imaging of choroidal vasculature and birefringence structures are demonstrated.
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passive component based multifunctional jones matrix swept source optical coherence tomography for doppler and Polarization imaging
Optics Letters, 2012Co-Authors: Youngjoo Hong, Lian Duan, Yoshiaki YasunoAbstract:We present a fiber based multifunctional Jones matrix swept source optical coherence tomography (SS-OCT) system for Doppler and Polarization imaging. Jones matrix measurement without using active components such as electro-optic modulators is realized by Incident Polarization multiplexing based on independent delay of two orthogonal Polarization states and Polarization diversity detection. In addition to Polarization sensitivity, this system measures Doppler flow without extra hardware for phase stabilized SS-OCT detection. An eighth-wave plate was measured to demonstrate the Polarization detection accuracy. The optic nerve head of a retina was measured in vivo. Detailed vasculature and birefringent structures were investigated simultaneously.
Shuichi Makita - One of the best experts on this subject based on the ideXlab platform.
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advanced multi contrast jones matrix optical coherence tomography for doppler and Polarization sensitive imaging
Optics Express, 2013Co-Authors: Youngjoo Hong, Shuichi Makita, Lian Duan, Masahiro Miura, Yiheng Lim, Kazuhiro Kurokawa, Shuo Tang, Yoshiaki YasunoAbstract:An advanced version of Jones matrix optical coherence tomography (JMT) is demonstrated for Doppler and Polarization sensitive imaging of the posterior eye. JMT is capable of providing localized flow tomography by Doppler detection and investigating the birefringence property of tissue through a three-dimensional (3-D) Jones matrix measurement. Owing to an Incident Polarization multiplexing scheme based on passive optical components, this system is stable, safe in a clinical environment, and cost effective. Since the properties of this version of JMT provide intrinsic compensation for system imperfection, the system is easy to calibrate. Compared with the previous version of JMT, this advanced JMT achieves a sufficiently long depth measurement range for clinical cases of posterior eye disease. Furthermore, a fine spectral shift compensation method based on the cross-correlation of calibration signals was devised for stabilizing the phase of OCT, which enables a high sensitivity Doppler OCT measurement. In addition, a new theory of JMT which integrates the Jones matrix measurement, Doppler measurement, and scattering measurement is presented. This theory enables a sensitivity-enhanced scattering OCT and high-sensitivity Doppler OCT. These new features enable the application of this system to clinical cases. A healthy subject and a geographic atrophy patient were measured in vivo, and simultaneous imaging of choroidal vasculature and birefringence structures are demonstrated.
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Polarization sensitive swept source optical coherence tomography with continuous source Polarization modulation
Optics Express, 2008Co-Authors: Masahiro Yamanari, Shuichi Makita, Yoshiaki YasunoAbstract:We present fiber-based Polarization-sensitive swept-source optical coherence tomography (SS-OCT) based on continuous source Polarization modulation. The light source is a frequency swept laser centered at 1.31 µm with a scanning rate of 20 kHz. The Incident Polarization is modulated by a resonant electro-optic modulator at 33.3 MHz, which is one-third of the data acquisition frequency. The zeroth- and first-order harmonic components of the OCT signals with respect to the Polarization modulation frequency have the polarimetric information of the sample. By algebraic and matrix calculations of the signals, this system can measure the depth-resolved Jones matrices of the sample with a single wavelength scan. The phase fluctuations of the starting trigger of wavelength scan and the Polarization modulation are cancelled by monitoring the OCT phase of a calibration mirror inserted into the sample arm. We demonstrate the potential of the system by the measurement of chicken breast muscle and the volumetric measurement of an in vivo human anterior eye segment. The phase retardation image shows an additional contrast in the fibrous tissue such as the collagen fiber in the trabecular meshwork and sclera.
Lihong V Wang - One of the best experts on this subject based on the ideXlab platform.
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fiber based Polarization sensitive mueller matrix optical coherence tomography with continuous source Polarization modulation
Applied Optics, 2005Co-Authors: Shuliang Jiao, Milos Todorovic, George Stoica, Lihong V WangAbstract:We report on a new configuration of fiber-based Polarization-sensitive Mueller matrix optical coherence tomography that permits the acquisition of the round-trip Jones matrix of a biological sample using only one light source and a single depth scan. In this new configuration, a Polarization modulator is used in the source arm to continuously modulate the Incident Polarization state for both the reference and the sample arms. The Jones matrix of the sample can be calculated from the two frequency terms in the two detection channels. The first term is modulated by the carrier frequency, which is determined by the longitudinal scanning mechanism, whereas the other term is modulated by the beat frequency between the carrier frequency and the second harmonic of the modulation frequency of the Polarization modulator. One important feature of this system is that, for the first time to our knowledge, the Jones matrix of the sample can be calculated with a single detection channel and a single measurement when diattenuation is negligible. The system was successfully tested by imaging both standard Polarization elements and biological samples.
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contrast mechanisms in Polarization sensitive mueller matrix optical coherence tomography and application in burn imaging
Applied Optics, 2003Co-Authors: Shuliang Jiao, George Stoica, Lihong V WangAbstract:We investigate the various contrast mechanisms provided by Polarization-sensitive (PS) Mueller-matrix optical coherence tomography (OCT). Our PS multichannel Mueller-matrix OCT is the first, to our knowledge, to offer simultaneously comprehensive Polarization-contrast mechanisms, including the amplitude of birefringence, the orientation of birefringence, and the diattenuation in addition to the Polarization-independent intensity contrast, all of which can be extracted from the measured Jones or the equivalent Mueller matrix. Theoretical analysis shows that when diattenuation is negligible, the round-trip Jones matrix represents a linear retarder, which is the foundation of conventional PS-OCT, and can be calculated with a single Incident Polarization state, although the one-way Jones matrix generally represents an elliptical retarder; otherwise, two Incident Polarization states are needed. The experimental results obtained from rat skin samples, which conform well with the histology, show that Mueller OCT provides complementary structural and functional information on biological samples and reveal that Polarization contrast is more sensitive to thermal degeneration of biological tissue than amplitude-based contrast. Thus, Mueller OCT has significant potential for application in the noninvasive assessment of burn depth.
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measurement and calculation of the two dimensional backscattering mueller matrix of a turbid medium
Optics Letters, 1998Co-Authors: Brent D Cameron, Lihong V Wang, George W Kattawar, M J Rakovic, Mehrube Mehrubeoglu, Sohi Rastegar, Gerard L CoteAbstract:We present both experimental and Monte Carlo–based simulation results for the diffusely backscattered intensity patterns that arise from illumination of a turbid medium with a polarized laser beam. A numerical method that allows the calculation of all 16 elements of the two-dimensional Muller matrix is used; moreover, it is shown that only seven matrix elements are independent. To validate our method, we compared our simulations with experimental measurements, using a turbid medium consisting of 2.02‐µm-diameter polystyrene spheres suspended in deionized water. By varying the Incident Polarization and the analyzer optics for the experimental measurements, we obtained the diffuse backscattering Mueller matrix elements. The experimental and the numerical results are in good agreement.
