A5088310507- Laser Material Processing Techniques
- Photoacoustic and Ultrasonic Imaging
- Surface and Thin Film Phenomena
- Optical Imaging and Spectroscopy Techniques
- Advanced Chemical Physics Studies
- Electron and X-Ray Spectroscopy Techniques
- Advanced Materials Characterization Techniques
- 3D Printing in Biomedical Research
- Laser-Matter Interactions and Applications
- Laser-induced spectroscopy and plasma
- Force Microscopy Techniques and Applications
- Infrared Thermography in Medicine
- Graphene research and applications
- Hemodynamic Monitoring and Therapy
- Ocular and Laser Science Research
- Laser-Ablation Synthesis of Nanoparticles
- Optical Coherence Tomography Applications
- Near-Field Optical Microscopy
- Ion-surface interactions and analysis
- Sustainability and Climate Change Governance
- Theoretical and Computational Physics
- Magnetic properties of thin films
- Magnetic Properties and Applications
- Advanced X-ray and CT Imaging
- Thermography and Photoacoustic Techniques
University of California, Irvine
1996-2024
Beckman Laser Institute and Medical Clinic
2001-2004
We investigate experimentally the physical processes underlying pulsed cellular microsurgery and micromanipulation using nanosecond 532- 1064-nm laser pulses focused at high numerical aperture. find that parameters employed for many microirradiation techniques are congruent with those leading to optical breakdown in water. determine size shape of laser-induced plasma, pressure emitted shock wave, energy cavitation bubble formed by expanding plasma. discuss implications results biophysical procedures.
Using time-resolved imaging, we investigated the lysis of confluent PtK2 cell cultures by pulsed laser microbeam irradiation. Images obtained at time delays 0.5 ns to 50 μs demonstrate be mediated laser-induced plasma formation resulting in pressure wave propagation and cavitation bubble formation. Image analysis enabled quantitative characterization dynamics. The zone damage exceeded size serves implicate expansion as primary agent injury.
We describe an optoacoustic imaging technique based on time-resolved measurements of laser-induced thermoelastic expansion. Tomographic images tissue phantoms are formed using such made at several locations following irradiation with a Q-switched Nd:YAG (λ=1064nm) laser pulse. Our system is modified Mach–Zehnder interferometer that measures surface displacement temporal resolution 4ns and sensitivity 0.3nm. Images from data sets acquired highly scattering provide better than 200μm show great...
Regional and global environmental challenges have become increasingly complex require broader solutions than a single discipline can provide. Although there is growing need for interdisciplinary research, many graduate education programs still train students within the confines of particular or specialty. The Ridge 2 Reef research traineeship program at University California, Irvine, aimed to provide transferable skill training prepare from different disciplines address current future...
We have conducted time-resolved studies of optical breakdown produced by the irradiation water using 6 ns Nd:YAG laser pulses 1064 nm and 532 wavelength focused at a numerical aperture NA=0.9. determined pulse energy threshold values for plasma formation to be 1.89 (mu) J 18.3 irradiation, respectively. These thresholds correspond irradiance 0.77 x 10<SUP>9</SUP> W/mm<SUP>2</SUP> 1.87 irradiation. For energies 1x, 2x, 5x, 10x above threshold, we length induced plasma, propagation speed peak...
Quasi-particles travel down a one-dimensional concentration gradient in thin metallic film composed of regions only gold and gold-titanium-gold multilayers. We obtain an image depending on whether the quasi-particles encounter multilayer.
Highly focused laser microbeams are being used with increasing regularity for targeted cell lysis, cellular microsurgery and molecular delivery via transient membrane permeabilization. To examine the mechanisms of induced we performed time-resolved imaging confluent PtK2 cultures following a single 6 ns, 532 nm Nd:YAG pulse. The pulse energies employed correspond to 1x 3x threshold plasma formation. resulting formation, pressure wave propagation cavitation bubble dynamics were imaged over...
POISe is a spectroscopic imaging technique based on the measurement of surface motion resulting from thermoelastic stress waves produced by short pulse laser irradiation optically heterogeneous turbid samples. Here we show capability to form tomographic images tissue phantoms using displacement measurements taken at several locations following sample with Q-switched Nd:YAG λ=1064 nm. The principal component modified Mach-Zehnder interferometer that provides temporal resolution 4 ns and...
A modified Mach Zehnder interferometer system has been developed to measure surface motion with 4 ns temporal resolution and 0.2 nm displacement sensitivity. We discuss its use the optical properties of homogeneous turbid media image heterogeneous volumes depths 1 cm 200 micrometer resolution.