The Experts below are selected from a list of 285 Experts worldwide ranked by ideXlab platform
P. J. Veitch - One of the best experts on this subject based on the ideXlab platform.
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short pulse actively q switched er YAG Lasers
Optics Express, 2016Co-Authors: D J Ottaway, Lachlan Harris, P. J. VeitchAbstract:We report the shortest duration pulses obtained to date from an actively Q-switched Er:YAG laser pumped by a low spectral and spatial brightness laser diode. The 14.5 ns, 6 mJ pulses were obtained using a 1470 nm laser diode end-pumped co-planar folded zigzag slab architecture. We also present an analytical model that accurately predicts the pulse energy-duration product achievable from virtually all Q-switched Er:YAG Lasers and high repetition rate quasi-three-level Q-switched Lasers in general.
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stable single frequency er YAG Lasers at 1 6 mu m
IEEE Journal of Quantum Electronics, 2010Co-Authors: N W H Chang, D J Ottaway, D J Hosken, J Munch, P. J. VeitchAbstract:Stable, single frequency Lasers in the eye-safe band are essential for coherent remote sensing. We describe an Er: YAG laser that is resonantly pumped using diode Lasers, and produces a polarized, single frequency, diffraction limited beam at 1645 nm with a frequency stability suitable for single-shot velocity measurements with a precision ≪ 0.1ms-1.
D J Ottaway - One of the best experts on this subject based on the ideXlab platform.
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short pulse actively q switched er YAG Lasers
Optics Express, 2016Co-Authors: D J Ottaway, Lachlan Harris, P. J. VeitchAbstract:We report the shortest duration pulses obtained to date from an actively Q-switched Er:YAG laser pumped by a low spectral and spatial brightness laser diode. The 14.5 ns, 6 mJ pulses were obtained using a 1470 nm laser diode end-pumped co-planar folded zigzag slab architecture. We also present an analytical model that accurately predicts the pulse energy-duration product achievable from virtually all Q-switched Er:YAG Lasers and high repetition rate quasi-three-level Q-switched Lasers in general.
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stable single frequency er YAG Lasers at 1 6 mu m
IEEE Journal of Quantum Electronics, 2010Co-Authors: N W H Chang, D J Ottaway, D J Hosken, J Munch, P. J. VeitchAbstract:Stable, single frequency Lasers in the eye-safe band are essential for coherent remote sensing. We describe an Er: YAG laser that is resonantly pumped using diode Lasers, and produces a polarized, single frequency, diffraction limited beam at 1645 nm with a frequency stability suitable for single-shot velocity measurements with a precision ≪ 0.1ms-1.
Victor E Ross - One of the best experts on this subject based on the ideXlab platform.
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comparison of responses of tattoos to picosecond and nanosecond q switched neodymium YAG Lasers
Archives of Dermatology, 1998Co-Authors: Victor E Ross, George S Naseef, Michael W Kelly, Norm Michaud, Thomas J Flotte, Jill Raythen, Rox R AndersonAbstract:Objective To test the hypothesis that picosecond laser pulses are more effective than nanosecond domain pulses in clearing of tattoos. Design Intratattoo comparison trial of 2 laser treatment modalities. Setting A large interdisciplinary biomedical laser laboratory on the campus of a tertiary medical center. Patients Consecutive patients with black tattoos were enrolled; all 16 patients completed the study. Intervention We treated designated parts of the same tattoo with 35-picosecond and 10-nanosecond pulses from 2 neodymium:YAG Lasers. Patients received a total of 4 treatments at 4-week intervals. All laser pulse parameters were held constant except pulse duration. Radiation exposure was 0.65 J/cm 2 at the skin surface. Biopsies were performed for routine microscopic and electron microscopic analysis at the initial treatment session and 4 weeks after the final treatment in 8 consenting patients. Also, ink samples were irradiated in vitro. Main Outcome Measures In vivo, on the completion of treatment, a panel of dermatologists not associated with the study (and blinded to the treatment type) evaluated photographs to assess tattoo lightening. Formalin-fixed specimens were examined for qualitative epidermal and dermal changes as well as depth of pigment alteration. Electron micrographs were examined for particle electron density and size changes (in vivo and in vitro). The gross in vitro optical density changes were measured. Results In 12 of 16 tattoos, there was significant lightening in the picosecond-treated areas compared with those treated with nanosecond pulses. Mean depth of pigment alteration was greater for picosecond pulses, but the difference was not significant. In vivo biopsy specimens showed similar electron-lucent changes for both pulse durations. In vitro results were similar for both pulse durations, showing increases in particle sizes and decreased electron density as well as gross ink lightening. Conclusions Picosecond pulses are more efficient than nanosecond pulses in clearing black tattoos. Black tattoos clear principally by laser-induced changes in the intrinsic optical properties of the ink.
Rox R Anderson - One of the best experts on this subject based on the ideXlab platform.
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comparison of responses of tattoos to picosecond and nanosecond q switched neodymium YAG Lasers
Archives of Dermatology, 1998Co-Authors: Victor E Ross, George S Naseef, Michael W Kelly, Norm Michaud, Thomas J Flotte, Jill Raythen, Rox R AndersonAbstract:Objective To test the hypothesis that picosecond laser pulses are more effective than nanosecond domain pulses in clearing of tattoos. Design Intratattoo comparison trial of 2 laser treatment modalities. Setting A large interdisciplinary biomedical laser laboratory on the campus of a tertiary medical center. Patients Consecutive patients with black tattoos were enrolled; all 16 patients completed the study. Intervention We treated designated parts of the same tattoo with 35-picosecond and 10-nanosecond pulses from 2 neodymium:YAG Lasers. Patients received a total of 4 treatments at 4-week intervals. All laser pulse parameters were held constant except pulse duration. Radiation exposure was 0.65 J/cm 2 at the skin surface. Biopsies were performed for routine microscopic and electron microscopic analysis at the initial treatment session and 4 weeks after the final treatment in 8 consenting patients. Also, ink samples were irradiated in vitro. Main Outcome Measures In vivo, on the completion of treatment, a panel of dermatologists not associated with the study (and blinded to the treatment type) evaluated photographs to assess tattoo lightening. Formalin-fixed specimens were examined for qualitative epidermal and dermal changes as well as depth of pigment alteration. Electron micrographs were examined for particle electron density and size changes (in vivo and in vitro). The gross in vitro optical density changes were measured. Results In 12 of 16 tattoos, there was significant lightening in the picosecond-treated areas compared with those treated with nanosecond pulses. Mean depth of pigment alteration was greater for picosecond pulses, but the difference was not significant. In vivo biopsy specimens showed similar electron-lucent changes for both pulse durations. In vitro results were similar for both pulse durations, showing increases in particle sizes and decreased electron density as well as gross ink lightening. Conclusions Picosecond pulses are more efficient than nanosecond pulses in clearing black tattoos. Black tattoos clear principally by laser-induced changes in the intrinsic optical properties of the ink.
Milton Birnbaum - One of the best experts on this subject based on the ideXlab platform.
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multiwatt continuous wave and q switched er YAG Lasers at 1645 nm performance issues
Optics Letters, 2009Co-Authors: Dawun Chen, Milton Birnbaum, Paul M Belden, Todd S Rose, Steven M BeckAbstract:The cw and Q-switched performance of Er:YAG Lasers operating at 1645 nm were measured. Guided by previous work in the literature, we sought to improve efficiency at low pulse repetition frequencies by decreasing the doping level from 0.5 to 0.25 at.% to reduce upconversion losses. Only a small improvement was obtained with this first-time-tested lower-doped material. Measurements of the fluorescence due to upconversion directly indicated that loss due to this process could not account for the observed power loss at low pulse repetition frequencies. Enhanced green emission during Q-switched operation, resulting from two-photon absorption of 1645 nm intracavity laser light, is reported for what we believe to be the first time. Measurements indicated that the output loss from this process is negligible.
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passive q switching of nd YAG Lasers by use of bulk semiconductors
Optics Letters, 1993Co-Authors: Y Tsou, Milton Birnbaum, Elsa Garmire, Wei Chen, Rajiv AsthanaAbstract:We report passive Q switching of Nd:YAG Lasers with the use of a bulk InGaAsP film, grown on an InP substrate by liquid-phase epitaxy, as an intracavity saturable absorber. The single Q-switched pulse had a maximum energy of 1.65 mJ with a 20-ns duration. The simple technology is easily extendible to any infrared solid-state laser.
