scholarly journals Optoacoustic Detection of Microparticles in Liquids at Laser Fluences Below the Optical Breakdown Threshold

1995 ◽  
Vol 16 (2) ◽  
pp. 63-73 ◽  
Author(s):  
S. S. Alimpiev ◽  
Ya. O. Simanovskii ◽  
S. V. Egerev ◽  
A. E. Pashin
Keyword(s):  
Excimer Laser ◽  
Optical Breakdown ◽  
Distilled Water ◽  
Breakdown Threshold ◽  
Laser Fluences ◽  
Informative Parameters ◽  
Measurement Cell ◽  
Xecl Excimer Laser

An optoacoustic device consisting of a XeCl excimer laser and a measurement cell with an attached piezotransducer was used for detecting microparticles suspended in liquid probes. The potential of optoacoustic diagnostics of microinhomogeneous liquids was enhanced by applying informative parameters of optoacoustic response. Probes of distilled water and Dow Chemical latex suspension were used in experiments. It was shown that cavitation mechanism of optoacoustic conversion taking place at laser fluences below the optical breakdown threshold was well-suited for individual microparticle detection. The approach proposed is different from the well-known breakdown counting optoacoustic technique.

Measurement of Polystyrene Nanospheres Using Excimer Laser Fragmentation Fluorescence Spectroscopy

2005 ◽  
Vol 59 (10) ◽  
pp. 1203-1208 ◽  
Author(s):  
Jong Hyun Choi ◽  
Catherine P. Koshland ◽  
Robert F. Sawyer ◽  
Donald Lucas
Keyword(s):  
Particle Interaction ◽  
Optical Breakdown ◽  
Continuum Emission ◽  
Breakdown Threshold ◽  
Dimensional Parameter ◽  
Atom Ratio ◽  
Laser Fluences ◽  
Polystyrene Nanospheres ◽  
Monodisperse Polystyrene ◽  
193 Nm

Monodisperse polystyrene nanospheres with a mean diameter of 102 nm are photofragmented with 193 nm light in N2 at laser fluences from 1 to 20 J/cm2. Carbon atom fluorescence at 248 nm from the disintegration of the particles is used as a signature of the polystyrene. The normalized fluorescence signals are self-similar with an exponential decay lifetime of ∼10 ns. At fluences above 17 J/cm2, optical breakdown occurs and a strong continuum emission is generated that lasts significantly longer. A non-dimensional parameter, the photon-to-atom ratio (PAR), is used to interpret the laser-particle interaction energetics. Carbon fluorescence from polystyrene particles is compared with that from soot, and a similarity between the two particles is observed when normalized with PAR. Carbon emission from bulk polystyrene was also measured. Similar emission signals were observed, but the breakdown threshold of the surface is significantly lower at 0.2 J/cm2.

Poly-Silicon TFT Annealing with XeCl Excimer Laser.

2000 ◽  
Vol 28 (1) ◽  
pp. 24-28 ◽  
Author(s):  
Junichi SHIDA ◽  
Naoyuki KOBAYASHI ◽  
Hideaki KUSAMA
Keyword(s):  
Excimer Laser ◽  
Poly Silicon ◽  
Xecl Excimer Laser

Control of SF6 discharge gap switch by XeCl excimer laser

1991 ◽  
Vol 111 (4) ◽  
pp. 46-51 ◽  
Author(s):  
Hisato Okuda ◽  
Kazuhisa Katayama ◽  
Xiaojun Wang ◽  
Katsumi Masugata ◽  
Kiyoshi Yatsui
Keyword(s):  
Excimer Laser ◽  
Sf6 Discharge ◽  
Discharge Gap ◽  
Xecl Excimer Laser

5 kHz high repetition rate and high power XeCl excimer laser

1995 ◽  
Vol 66 (11) ◽  
pp. 5162-5164 ◽  
Author(s):  
Tatsumi Goto ◽  
Koji Kakizaki ◽  
Shigeyuki Takagi ◽  
Noboru Okamoto ◽  
Saburo Sato ◽  
...  
Keyword(s):  
Excimer Laser ◽  
High Power ◽  
Repetition Rate ◽  
High Repetition Rate ◽  
High Repetition ◽  
Xecl Excimer Laser

In-vitro ablation of fibrocartilage by XeCl excimer laser

1991 ◽  
Author(s):  
Martin Buchelt ◽  
Thanassis Papaioannou ◽  
Michael C. Fishbein ◽  
Werner Peters ◽  
Clain Beeder ◽  
...  
Keyword(s):  
Excimer Laser ◽  
Xecl Excimer Laser

Surface hardening of SUS304 by irradiation with a KrF excimer laser in SiH4 gas ambient

1990 ◽  
Vol 5 (2) ◽  
pp. 265-270 ◽  
Author(s):  
Koji Sugioka ◽  
Hideo Tashiro ◽  
Koichi Toyoda ◽  
Eiichi Tamura ◽  
Keigo Nagasaka
Keyword(s):  
Excimer Laser ◽  
Surface Hardening ◽  
Continuous Distribution ◽  
Surface Hardness ◽  
Laser Pulses ◽  
High Concentration ◽  
Laser Fluences ◽  
High Adhesion ◽  
Krf Excimer Laser ◽  
Si Films

Surface hardening of SUS304 resulting from the process of doping and deposition of Si by irradiation of a KrF excimer laser beam in a SiH4 gas ambient is investigated, and variations of the surface hardness are examined for different numbers of laser pulses and the laser fluences. The hardening is due to Si incorporation in high concentration. The continuous distribution of Si atoms across the surface layer suggests that a very high adhesion strength of the deposited Si films can be formed. The specific process for surface modification is referred to as laser implant-deposition (LID).

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