The Experts below are selected from a list of 288 Experts worldwide ranked by ideXlab platform
Changhuei Yang - One of the best experts on this subject based on the ideXlab platform.
-
digital Optical Phase Conjugation of fluorescence in turbid tissue
Applied Physics Letters, 2012Co-Authors: Ivo Micha Vellekoop, Changhuei YangAbstract:We demonstrate a method for Phase conjugating fluorescence. Our method, called reference free digital Optical Phase Conjugation, can conjugate extremely weak, incoherent Optical signals. It was used to Phase conjugate fluorescent light originating from a bead covered with 0.5 mm of light-scattering tissue. The Phase conjugated beam refocuses onto the bead and causes a local increase of over two orders of magnitude in the light intensity. Potential applications are in imaging, Optical trapping, and targeted photochemical activation inside turbid tissue.
-
Towards deep tissue imaging by time-reversal Optical Phase Conjugation techniques
Ntm, 2011Co-Authors: Changhuei YangAbstract:We recently demonstrated that it is possible to use Optical Phase Conjugation as a means to time reverse the scattering of light through biological tissue 1. This newly observed phenomenon, termed turbidity suppression by Optical Phase Conjugation (TSOPC), can potentially be adapted for numerous biophotonics applications, such as coherent deep Optical imaging of tissue, enhanced light delivery for photodynamic therapy and high sensitivity absorption spectrum measurements. In this talk, we shall report on our recent findings and discuss the potential applications.
-
Deep tissue imaging by time-reversal Optical Phase Conjugation techniques
Photonics, 2010Co-Authors: Ying Min Wang, Changhuei YangAbstract:We recently demonstrated that it is possible to use Optical Phase Conjugation as a means to time reverse the scattering of light through biological tissue 1. This newly observed phenomenon, termed turbidity suppression by Optical Phase Conjugation (TSOPC), can potentially be adapted for numerous biophotonics applications, such as coherent deep Optical imaging of tissue, enhanced light delivery for photodynamic therapy and high sensitivity absorption spectrum measurements. In this talk, we shall report on our recent findings and discuss the potential applications.
-
Optical Phase Conjugation for Tissue Turbidity Suppression
Frontiers in Optics, 2009Co-Authors: Changhuei Yang, Emily J. McdowellAbstract:We will discuss our recent findings on the use of Optical-Phase-Conjugation to undo Optical tissue scatterings. Amongst other results, we discovered that light scattered hundreds of times still retains sufficient memory to enable path retracing.
-
Tissue Turbidity Suppression by Optical Phase Conjugation
IEEE Transactions on Biomedical Engineering, 2008Co-Authors: Zahid Yaqoob, Emily J. Mcdowell, Changhuei YangAbstract:Light scattering in tissue may appear random but it is causal and deterministic in nature. We report on our findings into the use of Optical Phase Conjugation (TS-OPC) for tissue turbidity suppression. Article not available.
Andrzej Miniewicz - One of the best experts on this subject based on the ideXlab platform.
-
Optical Phase Conjugation in azo dye doped chiral liquid crystal
Applied Physics Letters, 2012Co-Authors: Pawel Karpinski, Andrzej MiniewiczAbstract:We report on Optical Phase Conjugation phenomenon observed in chiral nematic liquid crystal showing band gap type Bragg reflection. The Phase conjugate to the signal beam is observable only in the small temperature interval when the Bragg condition is fulfilled and only for circularly polarized light. The Optical Phase Conjugation signals were observed at low cw laser light intensities (<100 mW/cm2, λ = 532 nm). Estimated value of third order Optical susceptibility χ(3) = 2.8 × 10−17 m2/V2 is attributed to enhancement due to photoisomerisation of azo-dye (disperse red 1) inducing molecular reorientation process of liquid crystal molecules.
-
Optical Phase Conjugation in azo-dye doped chiral liquid crystal
Applied Physics Letters, 2012Co-Authors: Pawel Karpinski, Andrzej MiniewiczAbstract:We report on Optical Phase Conjugation phenomenon observed in chiral nematic liquid crystal showing band gap type Bragg reflection. The Phase conjugate to the signal beam is observable only in the small temperature interval when the Bragg condition is fulfilled and only for circularly polarized light. The Optical Phase Conjugation signals were observed at low cw laser light intensities (
-
Biopolymer-based material for Optical Phase Conjugation
Journal of Optoelectronics and Advanced Materials, 2008Co-Authors: Jaroslaw Mysliwiec, O. Krupka, Ileana Rau, Andrzej Miniewicz, Francois Kajzar, B. Sahraoui, Jana GroteAbstract:We present results of Optical Phase Conjugation experiments in modified DNA (deoxyribonucleic acid) - dye system. The system consisted of a biopolymeric matrix made of DNA blended with cationic surfactant molecule cetyltrimethyl-ammonium chloride (CTMA) and doped with a photochromic dye Disperse Red 1. Results were obtained in a typical degenerate four wave mixing experiment. For sample excitation we used linearly polarized light at a wavelength 514.5 nm, delivered by an argon ion (Ar+) laser. The Phase conjugated signal which emerged from the sample had rise and fall time constants of a few milliseconds with an excellent reversibility.
Zongyan Wu - One of the best experts on this subject based on the ideXlab platform.
-
WDM transmissions exploiting Optical Phase Conjugation
Annales Des Télécommunications, 2007Co-Authors: Xuefeng Tang, Zongyan WuAbstract:Due to the frequency shift occurring in the process of Optical Phase Conjugation (opc) generation, the application of opc in multiple-channel transmission is limited severely by the third-order dispersion. In this paper, taking into account the influence of the frequency shift and the compensation of nonlinear effects, we present an effective method to optimize the dispersion map for broad-band transmissions using Optical Phase Conjugation. The numerical simulation results show that high efficiency wavelength-division-multiplexing (wdm) transmissions can be achieved by using the combination of opc with an optimized dispersion map.
-
WDM transmissions exploiting Optical Phase Conjugation
Annales Des Télécommunications, 2007Co-Authors: Xuefeng Tang, Zongyan WuAbstract:Due to the frequency shift occurring in the process of Optical Phase Conjugation ( opc ) generation, the application of opc in multiple-channel transmission is limited severely by the third-order dispersion. In this paper, taking into account the influence of the frequency shift and the compensation of nonlinear effects, we present an effective method to optimize the dispersion map for broad-band transmissions using Optical Phase Conjugation. The numerical simulation results show that high efficiency wavelength-division-multiplexing ( wdm ) transmissions can be achieved by using the combination of opc with an optimized dispersion map. Le déplacement de fréquence provoqué par la génération d’une conjugaison optique de Phase pourrait limiter l’application de celle-ci à la transmission multi-canaux à cause de la dispersion du 3^e ordre. Une méthode plus efficace est proposée pour optimiser le diagramme de dispersion dans la transmission à large bande; cette méthode a pris en compte l’effet du déplacement de fréquence et la compensation des effets non linéaires. Une étude de simulation montre que la transmission par multiplexage en longueur d’onde pourrait être plus efficace si la conjugaison de Phase était utilisée en association avec une optimisation du diagramme de dispersion.
-
Reduction of intrachannel nonlinearity using Optical Phase Conjugation
IEEE Photonics Technology Letters, 2005Co-Authors: Xuefeng Tang, Zongyan WuAbstract:We study the compensation process of nonlinear intrachannel interactions in Optical Phase Conjugation (OPC) systems using a perturbational approach. The theoretical analysis and numerical simulations reveal that the system impact of intrachannel effects can be greatly reduced by OPC combined with a symmetric fiber-link configuration.
Emily J. Mcdowell - One of the best experts on this subject based on the ideXlab platform.
-
Optical Phase Conjugation for Tissue Turbidity Suppression
Frontiers in Optics, 2009Co-Authors: Changhuei Yang, Emily J. McdowellAbstract:We will discuss our recent findings on the use of Optical-Phase-Conjugation to undo Optical tissue scatterings. Amongst other results, we discovered that light scattered hundreds of times still retains sufficient memory to enable path retracing.
-
Tissue Turbidity Suppression by Optical Phase Conjugation
IEEE Transactions on Biomedical Engineering, 2008Co-Authors: Zahid Yaqoob, Emily J. Mcdowell, Changhuei YangAbstract:Light scattering in tissue may appear random but it is causal and deterministic in nature. We report on our findings into the use of Optical Phase Conjugation (TS-OPC) for tissue turbidity suppression. Article not available.
-
a proposed deep tissue imaging scheme based on turbidity suppression Optical Phase Conjugation
IEEE Transactions on Biomedical Engineering, 2008Co-Authors: Emily J. Mcdowell, Zahid Yaqoob, Changhuei YangAbstract:We propose an imaging scheme based on turbidity suppression Optical Phase Conjugation (TSOPC), allowing for depth selective targeting of planes within a turbid medium.
Pawel Karpinski - One of the best experts on this subject based on the ideXlab platform.
-
Optical Phase Conjugation in azo dye doped chiral liquid crystal
Applied Physics Letters, 2012Co-Authors: Pawel Karpinski, Andrzej MiniewiczAbstract:We report on Optical Phase Conjugation phenomenon observed in chiral nematic liquid crystal showing band gap type Bragg reflection. The Phase conjugate to the signal beam is observable only in the small temperature interval when the Bragg condition is fulfilled and only for circularly polarized light. The Optical Phase Conjugation signals were observed at low cw laser light intensities (<100 mW/cm2, λ = 532 nm). Estimated value of third order Optical susceptibility χ(3) = 2.8 × 10−17 m2/V2 is attributed to enhancement due to photoisomerisation of azo-dye (disperse red 1) inducing molecular reorientation process of liquid crystal molecules.
-
Optical Phase Conjugation in azo-dye doped chiral liquid crystal
Applied Physics Letters, 2012Co-Authors: Pawel Karpinski, Andrzej MiniewiczAbstract:We report on Optical Phase Conjugation phenomenon observed in chiral nematic liquid crystal showing band gap type Bragg reflection. The Phase conjugate to the signal beam is observable only in the small temperature interval when the Bragg condition is fulfilled and only for circularly polarized light. The Optical Phase Conjugation signals were observed at low cw laser light intensities (