The Experts below are selected from a list of 10236 Experts worldwide ranked by ideXlab platform

Stojan Radic - One of the best experts on this subject based on the ideXlab platform.

Lihong V Wang - One of the best experts on this subject based on the ideXlab platform.

  • Frequency-Swept Ultrasound-Modulated Optical Tomography
    Advances in Optical Imaging and Photon Migration, 1998
    Co-Authors: Lihong V Wang
    Abstract:

    A novel frequency-swept (chirped) ultrasound Modulated Optical tomography technique was developed to image scattering media. Laser light was Modulated by a frequency-swept ultrasonic wave to add spatial information to the Modulated Optical Signal. The Modulated Optical Signal was received by a photomultiplier tube and was heterodyned with a reference modulation Signal. Frequency analysis was employed to obtain spatial resolution along the ultrasonic axis. A spectrum can be converted to a ID image. Multiple spectra were obtained and were used to form a 2D image of the scattering medium.

  • Turbid acousto-optics and its potential for biomedical applications
    Proceedings of the 19th Annual International Conference of the IEEE Engineering in Medicine and Biology Society. 'Magnificent Milestones and Emerging , 1997
    Co-Authors: Lihong V Wang
    Abstract:

    Continuous-wave ultrasonic modulation of scattered laser light has been used to image objects in tissue-simulating turbid media for the first time. The Modulated laser light collected by a photomultiplier tube reflected the local mechanical and Optical properties in the modulation zone. Buried objects in 5-cm thick tissue phantoms were imaged with millimeter resolution by scanning and detecting alterations of the ultrasound-Modulated Optical Signal. The tissue phantoms had the following Optical properties: absorption coefficient /spl mu//sub a/=0.1 cm/sup -1/, reduced scattering coefficient /spl mu//sub s/'=10 cm/sup -1/, which are comparable with those of biological tissues in the visible and near IR range. This technique is merely a representation of a much broader discipline coined turbid acousto-optics, which means acousto-optics in turbid media.

  • Ultrasound-Modulated Optical tomography of absorbing objects buried in dense tissue-simulating turbid media
    Applied optics, 1997
    Co-Authors: Lihong V Wang, Xuemei Zhao
    Abstract:

    Continuous-wave ultrasonic modulation of scattered laser light was used to image objects buried in tissue-simulating turbid media. The buried object had an absorption coefficient greater than the background turbid medium. The ultrasonic wave that was focused into the turbid media Modulated the laser light that passed through the ultrasonic field. The Modulated laser light that was collected by a photomultiplier tube reflected the local mechanical and Optical properties in the zone of ultrasonic modulation. Objects buried in the middle plane of 5-cm-thick dense turbid media were imaged with millimeter resolution through the scanning and detecting alterations of the ultrasound-Modulated Optical Signal. The Optical properties of the dense turbid media included an absorption coefficient of 0.1 cm-1 and a reduced scattering coefficient of 10 cm-1 and were comparable with those of biological tissues in the visible and near-IR ranges. The dependence of the ultrasound-Modulated Optical Signal on the off-axis distance of the detector from the optic axis and the area of the detector was studied as well.

  • continuous wave ultrasonic modulation of scattered laser light to image objects in turbid media
    Optics Letters, 1995
    Co-Authors: Lihong V Wang, Steven L Jacques, Xuemei Zhao
    Abstract:

    Continuous-wave ultrasonic modulation of scattered laser light has been used to image objects in tissue-simulating turbid media for what is to our knowledge the first time. The ultrasound wave focused into the turbid media modulates the laser light passing through the ultrasonic focal zone. The Modulated laser light collected by a photomultiplier tube reflects the local mechanical and Optical properties in the focal zone. Buried objects are located with millimeter resolution by scanning and detecting alterations of the Modulated Optical Signal. This technique has the potential to provide a noninvasive, nonionizing, inexpensive diagnostic tool for diseases such as breast cancer.

A J Seeds - One of the best experts on this subject based on the ideXlab platform.

Xuemei Zhao - One of the best experts on this subject based on the ideXlab platform.

  • Ultrasound-Modulated Optical tomography of absorbing objects buried in dense tissue-simulating turbid media
    Applied optics, 1997
    Co-Authors: Lihong V Wang, Xuemei Zhao
    Abstract:

    Continuous-wave ultrasonic modulation of scattered laser light was used to image objects buried in tissue-simulating turbid media. The buried object had an absorption coefficient greater than the background turbid medium. The ultrasonic wave that was focused into the turbid media Modulated the laser light that passed through the ultrasonic field. The Modulated laser light that was collected by a photomultiplier tube reflected the local mechanical and Optical properties in the zone of ultrasonic modulation. Objects buried in the middle plane of 5-cm-thick dense turbid media were imaged with millimeter resolution through the scanning and detecting alterations of the ultrasound-Modulated Optical Signal. The Optical properties of the dense turbid media included an absorption coefficient of 0.1 cm-1 and a reduced scattering coefficient of 10 cm-1 and were comparable with those of biological tissues in the visible and near-IR ranges. The dependence of the ultrasound-Modulated Optical Signal on the off-axis distance of the detector from the optic axis and the area of the detector was studied as well.

  • continuous wave ultrasonic modulation of scattered laser light to image objects in turbid media
    Optics Letters, 1995
    Co-Authors: Lihong V Wang, Steven L Jacques, Xuemei Zhao
    Abstract:

    Continuous-wave ultrasonic modulation of scattered laser light has been used to image objects in tissue-simulating turbid media for what is to our knowledge the first time. The ultrasound wave focused into the turbid media modulates the laser light passing through the ultrasonic focal zone. The Modulated laser light collected by a photomultiplier tube reflects the local mechanical and Optical properties in the focal zone. Buried objects are located with millimeter resolution by scanning and detecting alterations of the Modulated Optical Signal. This technique has the potential to provide a noninvasive, nonionizing, inexpensive diagnostic tool for diseases such as breast cancer.

R A Minasian - One of the best experts on this subject based on the ideXlab platform.

  • microwave photonic Signal processing
    Optics Express, 2013
    Co-Authors: R A Minasian, Erwin H W Chan
    Abstract:

    Photonic Signal processing offers the advantages of large time-bandwidth capabilities to overcome inherent electronic limitations. In-fibre Signal processors are inherently compatible with fibre optic microwave systems that can integrate with wireless antennas, and can provide connectivity with in-built Signal conditioning and electromagnetic interference immunity. Recent methods in wideband and adaptive Signal processing, which address the challenge of realising programmable microwave photonic phase shifters and true-time delay elements for phased array beamforming; ultra-wideband Hilbert transformers; single passband, widely tunable, and switchable microwave photonic filters; and ultra-wideband microwave photonic mixers, are described. In addition, a new microwave photonic mixer structure is presented, which is based on using the inherent frequency selectivity of the stimulated Brillouin scattering loss spectrum to suppress the carrier of a dual-phase Modulated Optical Signal. Results for the new microwave photonic mixer demonstrate an extremely wide bandwidth operation of 0.2 to 20 GHz and a large conversion efficiency improvement compared to the conventional microwave photonic mixer.

  • widely tunable single passband microwave photonic filter based on stimulated brillouin scattering
    IEEE Photonics Technology Letters, 2011
    Co-Authors: Weiwei Zhang, R A Minasian
    Abstract:

    A new ultrawide continuously tunable single-passband microwave photonic filter with very high resolution, is presented. It is based on a stimulated Brillouin scattering technique using a phase Modulated Optical Signal and a dual-sideband suppressed-carrier pump. Results are presented which demonstrate a 1- to 20-GHz measured tuning range, together with continuous tuning, extremely high resolution with a -3-dB bandwidth of only 20 MHz, a single passband, shape-invariant tuning, and a high out-of-band rejection of 31 dB.